9th International Symposium on Tardigrada St. Pete Beach ... · Tardigrade Research: Where Have We Been? Where Are We Going? 10:30am Morning Break Mediterranean Palm Session 2 Phylogeny

9th International Symposium on Tardigrada St. Pete Beach, FL

28 July – 1 August 2003

Program of Events

Date/Time Event Location_________ Sunday July 27, 2003 6:00pm – 8:00pm Welcome Social Beachfront Breezeway Monday July 28, 2003 Session 1 Welcome Mediterranean Palm 9:00am Jim Garey, Symposium Committee Chair 9:10am Sandy Schneider, Associate Dean of Research, USF 9:30am Diane Nelson, East Tennessee State University Tardigrade Research: Where Have We Been? Where Are We Going? 10:30am Morning Break Mediterranean Palm Session 2 Phylogeny Mediterranean Palm 11:00am Jerome Reiger, University of Maryland 12:00 – 1:30pm Lunch Royal Palm – 8th Floor

1:30pm Mark Blaxter, University of Edinburgh

Molecular phylogenetics of the Tardigrada and an investigation of the position of tardigrades in animal phylogeny

2:00pm Jette Eibye-Jacobsen, University of Copenhagen

Three dimensional understanding of the foremost section of the buccal apparatus of Echiniscus viridissimus Peterfi, 1956 (Heterotardigrada)

2:30pm Ruth Dewel, Appalachian State University

Origin and Diversification of the Arthropods: New Interpretations of Some Old Characters 3:00pm Afternoon Break Mediterranean Palm 3:30pm Roberto Bertolani, University of Modena

Phylogenetic relationships in Macrobiotidae (Tardigrada). II. Molecular (mtDNA) and morphological approaches

4:00pm P. Brent Nichols, University of South Florida Family Values: A Cladistic Analysis of the Tardigrada

9th International Symposium on Tardigrada

St. Pete Beach, Florida USA 27 July – 1 August, 2003

2 Date/Time Event Location_________ Tuesday July 29, 2003 Session 1 Life History – Temperate Mediterranean Palm 9:00am Tiziana Altiero, University of Modena

Phenotypic life history variations in two clones of Macrobiotus richtersi

9:30am Harry Meyer, McNeese State University Distribution of Terrestrial Tardigrades in the State of Florida 10:00am Nigel Marley, University of Plymouth Preliminary Results from a Study on Ecuadorian Tardigrada 10:30am Morning Break Mediterranean Palm 11:00am Juliana Hinton, McNeese State University

Seasonal and Spatial Variation in Tardigrade Diversity in Leaf Litter from Florida and Louisiana 11:30am Paul Bartels, Warren Wilson College A Large-scale, Multi-Habitat Inventory of Tardigrades in the Great Smoky Mountains

National Park. 12:00 – 1:30pm Lunch Royal Palm – 8th Floor Session 2 Poster Session 1 Sabal - Canary Palm 3rd Floor 1:30pm Wataru Abe, Hokkaido University Semiterrestrial Tardigrades form Sakhalin Island, Far East Russia Jennifer Daub, University of Edinburgh Genomic Resources for the Tardigrade Hypsibius dujardini Peter Degma, Comenius University The Ecological Distribution of Tardigrada in National Nature Reserve Stužica (Bukovské vrchy Mts , NE Slovakia ) Maria Fernandez, Universidad Nacional de La Pampa Population Dynamics of Dactylobiotus grandipes Schuster et al., 1977 (Tardigrada) in a Neotropical Eutophic Pond. Roberto Guidetti, University of Modena Dactylobiotus octavi n. sp. (Eutardigrada; Macrobiotidae) from Disko Island



3 Date/Time Event Location_________ Session 2 Poster Session 1- cont. Sabal - Canary Palm 3rd Floor Jesper Hansen, University of Copenhagen The “Hyena Female” within the Marine Tardigrada with the Description of Two New Species of Megastygarctides (Arthrotardigrada: Stygarctidae) from Saudi Arabia Nigel Marley, University of Plymouth Designation of Pseudobiotus kathmanae Nelson (Tardigrada) as the Type Species of Pseudobiotus Nelson.

Daiki Horikawa, Hokkaido University The Effects of Prehydration on the Anhydrobiotic Survival in the Tardigrade Milnesium tardigradum Javier Jerez-Jaimes, University of Puerto Rico Tardigrades in Six Phorphytes of the Moss Calymperes tenerum C. Müller

ElianaNarvaea, University of PuertoRico Tardigrade Community Composition in Four ForestTypes in the El Divisio Reserve, (Santander, Colombia) Atsushi Suzuki, University of Keio

Oogenesis of Milnesium tardigradum

Sandra McInness, British Antarctic Survey Exceptional, Tardigrade Dominated Ecosystems in Ellsworth Land, Antarctica. Diana Sucharski, Chestnut Hill College Tardigrades of North America: Southeastern Pennsylvania 3:00pm Afternoon Break Mediterranean Palm 3:30pm FreeTime/Late Additions



4 Date/Time Event Location_________ Wednesday July 30, 2003 Session 1 Life History – Polar and Sub-polar Mediterranean Palm 9:30am Michael Collins, University of Newfoundland A Preliminary Account of Tardigrades of Labrador, Canada 10:00am Randy Miller, Chestnut Hill College Tardigrades of the Sub-Antarctic: 5000 year old eggs from Marion Island

10:30am Morning Break Mediterranean Palm 11:00am Jesper Hansen, University of Copenhagen

A Study on the Genus Amphibolus from Disko Island, Greenland, with Special Attention on the Life Cycle of Amphibolus nebulosus (Eutardigrada: Eohypsibiidae)

11:30am Matthew Boeckner, University of Newfoundland Factors Affecting the Ecology of Tardigrada in Labrador, Canada with Relation to Elevation, Latitude, Seasonality, and Desiccation Tolerance.

12:00 – 12:30pm Lunch Boxed Lunch 12:30pm Busch Gardens Resort Entrance



5 Date/Time Event Location_________ Thursday July 31, 2003 Session 1 Life History -- Marine Mediterranean Palm 9:45am Tom Boesgaard, University of Copenhagen The Tardigrade Fauna of Two Australian Marine Caves With Descriptions of Six New Species of Arthrotardigrada. 9:45am Iben Heiner, University of Copenhagen

A Revision of the Marine Genus Orzeliscus, Arthrotardigrada, Tardigrada 10:30am Morning Break Mediterranean Palm 11:00am Reinhardt Kristensen, University of Copenhagen Extreme Secondary Sexual Dimorphism in the Genus Florarctus (Arthrotardigrada: Halechiniscidae) 11:30am Clark Beasley, McMurry University Additions to the Tardigrada Fauna of China 12:00 – 1:30pm Lunch Royal Palm – 8th Floor Session 2 Poster Session 2 Sabal - Canary Palm 3rd Floor 1:30pm Łukasz Kaczmarek, A Mickiewicz University Milnesium katarzynae sp. nov., a New Species of Eutardigrade from China Hiroki Harada, Yokohama National University The response of Soil-Inhabiting Tardigrade Communities to Various Forests in the Southern Part of Kanagawa Prefacture.

Nigel Marley, University of Plymouth Tardigrades of Southwest England, United Kingdom. A Long-term, Multi-habitat Survey from the Coastal Urban Habitats to the Upland Moors. Clayton Marshall, Eastern High School A Comparative Study of Souther Indiana Urban and Rural Tardigrade Populations Due to Seasonal Environmental pH Changes. Harry Meyer, McNeese State University Small-scale Spatial Variability in Terrestrial Tardigrade Populations. Maria Moly de Peluffo, Universidad Nacional de La Pampa Tardigrade Distributions in a Medium-sized City of Central Argentina



6 Date/Time Event Location_________ Session 2 Poster Session 2- cont. Sabal - Canary Palm 3rd Floor Lorena Rebecchi, University of Modena Resting Eggs in Tardigrades Fran Thomas, University of Edinburgh Establishment of a Culture System for and Lifecycle Dynamics of the Tardigrade Hypsibius dujardini Birna Trygvadottir, University of Copenhagen Tardigrades of the Faroe Islands Karsten Klage, Virginia Tech University Tardigrades – Understanding Dessication Tolerance. Sandra McInness, British AntarcticSurvey Tardigrade faunaof Sub-Antarctic Marion Island in the Prince Edward Archipelago,

South Indian Ocean – A Preliminary Report. Sandra McInness, British Antarctic Survey Tardigrade Fauna of the South Sandwich Islands

Randy Miller, Chestnut Hill College Tardigrades of North America: Central Park, New York City, New York, U.S.A. 3:00pm Afternoon Break Mediterranean Palm Session 3 Taxonomy & Methods Mediterranean Palm 3:30pm Habib Maroon, University of Edinburgh Adult and Embryonic Anatomy of Hypsibius dujardini 4:00pm Randy Miller, Chestnut Hill College Auto-Montage Imaging for Tardigrades 4:30pm Jonnathan Herrera-Vásquez, University of Costa Rica Tardigrades Density and Diversity in Four Life Zones of Costa Rica.



7 Date/Time Event Location_________ Friday August 1, 2003 Session 1 Physiology Mediterranean Palm 9:00am Richard Helm, Virginia Tech University Tardigrades and Biomimetic Cell Stabilization 10:00am Lorena Rebecchi, University of Modena Long-term Anhydrobiotic Survival of Lichen-dwelling Tardigrades 10:30am Morning Break Mediterranean Palm 11:00am Roberto Guidetti, University of Modena Encystment in Eutardigrades: Differences and Common Traits in Two Evolutionary Lines 12:00pm Open Forum 1:00 – 2:00pm Lunch Royal Palm – 8th Floor



8

Semiterrestrial Tardigrades from Sakhalin Island, Far East Russia

Wataru ABE

Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo, Japan Abstract. No report on the tardigrades from the Sakhalin Island has been made until now. In

July and August 2001 faunal survey on the semiterrestrial tardigrades was conducted in Sakhalin

Island, Far East Russia as a part of the International Sakhalin Island Project (ISIP), which is an

international collaboration of Russia, USA, and Japanese scientists. Mosses and lichens growing

mainly on trees and rocks were sampled to survey the tardigrade fauna. As a result, species

belonging to the following 10 genera representing 4 families were collected: Echiniscus,

Hypechiniscus, Pseudechiniscus, Testechiniscus, Diphascon, Itaquascon, Ramazzottius,

Macrobiotus, Minibiotus, and Milnesium. Faunal characteristics of the tardigrades from the

Sakhalin Island will be discussed on the basis of the comparison with those from sorrounding

areas including Japan.



9

Phenotypic life history variations in two clones of Macrobiotus richtersi (Eutardigrada, Macrobiotidae)

Tiziana ALTIERO, Lorena REBECCHI, and Roberto BERTOLANI

Department of Animal Biology, University of Modena and Reggio Emilia, Modena, Italy.

Abstract. The study of life history traits is focal to understand animal evolution and adaptations.

Recent identification of rearing methods for freshwater and semiterrestrial eutardigrades under

controlled conditions (Altiero and Rebecchi, 2001, Zool. Anz. 240: 217-221), allowed us to

overcome the limits imposed by the utilisation of animals exclusively derived from nature for the

analysis of different aspects of tardigrade biology, including life history. Therefore, a

comparative study of some life history traits has been realised under experimental conditions

using two clones (namely, CDMr01 and CDMr02) of a triploid thelytokous apomictic population

of Macrobiotus richtersi found in Italy. Both clones were reared at the same conditions:

temperature of 14°C, photoperiod of 12 h/12 h (L/D), and nematode ad libitum as food. Intra-

and interclonal variability has been observed for most life history traits analysed. Similarities

between clones have been observed as regards life span, total number of ovipositions per life

span, and age at first oviposition. The two clones were significantly different for number of eggs

per clutch (fertility; p < 0.001), number of eggs laid by each female in its life span (fecundity; p

< 0.05), hatching percentage of eggs (p < 0.05) and embryonic development length (p < 0.001).

Having all specimens the same genotype, differences in life history traits between clones should

be interpreted as phenotypic variations. Hatching phenology suggests that resting eggs could

exist also in tardigrades, opening a new field of study on the life history traits of these animals.



10

A Large-scale, Multi-Habitat Inventory of Tardigrades in the Great Smoky Mountains National Park

Paul J. BARTELS1 and Diane R. NELSON2

1Department of Environmental Studies & the Environmental Leadership Center, Warren Wilson College,

Asheville, North Carolina, U.S.A.

2Department of Biological Sciences, East Tennessee State University, Johnson City, Tennessee, U.S.A.

Abstract. An All Taxa Biodiversity Inventory (ATBI) is underway in the Great Smoky

Mountains National Park (GSMNP), attempting to identify all species of life in the 2000 km2

park. The GSMNP is a U.N. Biosphere Reserve and one of the largest protected temperate,

deciduous forests in the world. We have completed two field seasons of work on the tardigrades

of the park (2001-2002). To date we have collected over 400 samples from soil, lichen and moss

on trees, stream sediment and periphyton, and caves. Terrestrial samples were taken from within

permanent plots established for the ATBI, representing the major biological communities of the

GSMNP. Tardigrades were extracted from samples using centrifugation with LudoxTM,

individually mounted in Hoyer’s medium, and studied with phase-contrast microscopy. We have

identified 1663 specimens from approximately 70 samples. Only one study of tardigrades had

been previously reported for the park prior to our work, recording only three species. We have

identified 42 species, three of which may be new to science. Species richness estimates were

calculated for each of the major tardigrade habitats. Overall, our database predicts that there are

47 to 76 species in the GSMNP, with generally similar species richness in soil, lichen, moss, and

stream habitats. Species richness estimators were used to compare tree moss at ground level and

at breast height. Species richness was greater at breast height.



11

Additions to the Tardigrada Fauna of China

CLARK W. BEASLEY1, ŁUKASZ KACZMAREK2, AND ŁUKASZ MICHALCZYK3 1Department of Biology, McMurry University, Abilene, Texas 79697, U.S.A.; e-mail: [email protected] 2Department of Animal Taxonomy & Ecology, Institute of Environmental Biology, A. Mickiewicz University, Szamarzewskiego 91 a, 60-569 Pozna½, Poland; e-mail: [email protected] 3Institute of Environmental Sciences, Jagiellonian University, Ingardena 6, 30-060 Kraków, Poland; e-mail: [email protected] Abstract. A total of 95 habitat samples, primarily lichen and moss, from the Chinese Provinces

of Sichuan and Yunnan were examined. The samples came from altitudes ranging from 2600 to

3850 m asl. Twenty-six species were recovered. One species, Milnesium katarzynae is new for

science and is described in a separate paper. Species which are new records for China include

Bryodelphax tatrensis, Echiniscus nepalensis, Echiniscus reticulatus, Echiniscus spiniger,

Isohypsibius sattleri, Diphascon (Diphascon) pingue, Diphascon (Adropion) scoticum,

Diphascon (Adropion) prorsirostre, Mesocrista spitsbergense, Platicrista angustata, and

Doryphoribius cf. zyxiglobus. Three species are new records for both Sichuan and Yunnan

Provinces: Macrobiotus cf. hufelandi, Minibiotus intermedius, and Hypsibius pallidus. Four

species are new records for Sichuan Province: Echiniscus sp. ‘arctomys-group’, Macrobiotus cf.

harmsworthi, Minibiotus sp., and Murrayon sp. Three species are new records for Yunnan

Province: Cornechiniscus lobatus, Pseudechiniscus jiroveci, and Doryphoribius citrinus.

Although not new records, Echiniscus testudo, Pseudechiniscus suillus, and Milnesium

tardigradum were also collected from Sichuan Province. Bryodelphax tatrensis and Milnesium

tardigradum were also found in moss samples from Xizang Province, Tibet.



12

Phylogenetic relationships in Macrobiotidae (Tardigrada). II. Molecular (mtDNA) and morphological approaches

Roberto GUIDETTI1, Andrea GANDOLFI2, Valeria ROSSI2, and Roberto BERTOLANI1

1 Department of Animal Biology, University of Modena and Reggio Emilia, Modena , Italy

2 Department of Environmental Sciences , University of Parma , Parma , Italy .

Abstract. Molecular analyses on tardigrades are still at the beginning. First studies based on

18S rDNA considered the phylogenetic relationships between these organisms and other

invertebrates, in particular arthropods and nematodes (Giribert et al. 1996; Garey et al. 1996;

Moon & Kim 1996; Aguinaldo et al. 1997). Successively, a molecular study (18S rRNA) within

the phylum tested the validity of the actual classification at order level (based on morphological

data; Garey et al. 1999). The present study has been carried out on Macrobiotidae (one of the

most represented families of eutardigrades) using two different approaches: morphological and

molecular. The morphological approach refers to up dated considerations presented in a previous

paper (Guidetti & Bertolani 2001, Zool. Anz. 240: 371-376), whereas the molecular analysis has

been done on mitochondrial DNA, which was considered for the first time in these organisms.

Eight species have been analysed at molecular level (Dactylobiotus parthenogeneticus,

Murrayon pullari, Macrobiotus terminalis, Macrobiotus sp., Macrobiotus richtersi, Xerobiotus

pseudohufelandi, Ricthersius coronifer and Amphibolus volubilis as outgroup). The

morphological and molecular data give similar results and confirm the previous phylogenetic

evaluations on the main evolutionary lines (Murrayinae and Macrobiotinae) within the

Macrobiotidae. In particular, the strict phylogenetic relationship between Murrayon and

Dactylobiotus (Murrayinae) and the polyphyletic nature of Macrobiotus has been evidenced.

Macrobiotus sp. and M. terminalis (both belonging to the “hufelandi group”) look more related

to X. pseudohufelandi than to M. richtersi. The R. coronifer position is still uncertain.



13

Molecular phylogenetics of the Tardigrada and an investigation of the position of tardigrades in animal phylogeny

Mark BLAXTER , Ben ELSWORTH, Jennifer DAUB, Habib MAROON,

Aziz ABOOBAKER, and Fran THOMAS

Institute of Cell, Animal and Population Biology, Ashworth Laboratories, University of Edinburgh, King’s Buildings, Edinburgh EH9 3JT, UK

Abstract: We have initiated a program of evolutionary developmental biology research on a

cultured tardigrade, Hypsibius dujardini. Tardigrades are an attractive organism for comparative

work because of their basal position in the pan-Arthropoda, and the observation that they share

some morphological and developmental characteristics with other Ecdysozoa such as the

nematodes. Many molecular and morphological analyses now agree that tardigrades should be

included within the Ecdysozoa, but have yielded divergent positions within the superphylum.

Small subunit ribosomal RNA genes place tardigrades in a nematode-priapulid branch, while

morphology unequivocally suggests an onychophoran-arthropod association.

We are investigating tardigrade phylogeny by (1) sequencing small subunit ribosomal RNA

genes from additional species and (2) using other nuclear and mitochondrial genes. We are able

to amplify SSU genes from individual tardigrades isolated from the wild and thus have

assembled a reasonable dataset of SSU sequences. The tardigrade-derived SSU dataset yields a

new view of tardigrade diversity. Our ongoing EST project on Hypsibius dujardini (see poster by

J. Daub et al) has yielded a near-complete set of mitochondrial genes, and also many nuclear

genes that can be used to analyse tardigrade phylogeny. Our developmental biology program is

also generating sequences for conserved regulatory genes such as HOX and PAR genes. The

assembled datasets still yield a tardigrade-nematode association, but this appears to be due, to

some extent, to long branch attraction.



14

Factors Affecting the Ecology of Tardigrada in Labrador, Canada with Relation to Elevation, Latitude, Seasonality and Desiccation Tolerance.

Matthew J. BOECKNER1, Michael A.J. COLLINS1, and Lois BATEMAN2

1 Department of Biology, Memorial University of Newfoundland , St. John’s , Newfoundland and Labrador , Canada 2 Science Division, Sir Wilfred Grenfell College , Memorial University of Newfoundland , Corner Brook , Newfoundland and Labrador , Canada Abstract. Tardigrades are identified from mosses quantitatively sampled from varying

elevations, latitudes, seasons and horizon depths within coastal Labrador, Canada. Non-metric

multidimensional scaling is used to determine the relationships these environmental variables

have on the distribution, abundance and richness of tardigrade communities. Species that are

limited to specific environments as well as those with more cosmopolitan distributions are

indicated. Tardigrade distribution and richness throughout the samples was most strongly

correlated with the tendency for the moss to desiccate and most weakly correlated with latitude.

An elevational trend is discussed for M. c.f. hufelandi, which is strongly correlated with low

elevations. Nearly all of the tardigrade eggs were collected in the late summer and belonged to

M. echinogenitus, suggesting a strong relationship between reproduction and seasonality for this

species. Distribution patterns and ecological preference of individual species in relation to these

four environmental factors is discussed and compared to similar studies conducted worldwide.



15

The Tardigrade Fauna of Two Australian Marine Caves . With descriptions of six new species of Arthrotardigrada

Tom M. BOESGAARD and Reinhardt Mbjerg KRISTENSEN

Invertebrate Department, Zoological Museum, University of Copenhagen , Denmark . Abstract. Two marine caves in Australia have been investigated for meiofauna using the

freshwater technique to shock large sediment samples. Several species of nematodes,

gastrotrichs, crustaceans, polychaetes and aplacophorans were found, and one new species of

kinorhynchs has been described. Furthermore, two new species of loriciferans from marine caves

in New South Wales , Australia are right now under description. This paper is the fourth in a

series describing the unique meiofauna in submarine caves and inland anchialine caves of

Australia . The paper give a full description of the tardigrade fauna of the caves, Jim's Cave and

Fish Rock Cave , both located off the coast of New South Wales . The sediment consist of

carbonate sediments mixed with organic detritus.

The abundance of tardigrades is very low in the two caves, but the species diversity is very

high. Until now the following arthrotardigrade genera are found: Actinarctus, Batillipes,

Dipodarctus, Halechiniscus, Raiarctus, Styraconyx, Tanarctus, Tholoarctus, and

Wingstrandarctus. Two species of Dipodarctus, two species of Wingstrandarctus, one species of

Batillipes, and one species of Tanarctus are new for science. The new species of Tanarctus is also

found in the North Atlantic . The cave fauna of tardigrades seems not to be very related to the well-

investigated high energy beach fauna of tardigrades along the East Coast of Australia. Most

surprising is the finding of several species known from the Italian caves (e.g. Arctinarctus

neretinus) supporting the theory that marine caves serves as refugees for an old Tethyan fauna.



16

A Preliminary Account of the Tardigrades of Labrador, Canada

Michael A.J. COLLINS1, Matthew J. BOECKNER1, and Lois BATEMAN2

1 Department of Biology, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada 2 Science Division, Sir Wilfred Grenfell College, Memorial University of Newfoundland, Corner Brook, Newfoundland and Labrador, Canada

Abstract. This is the first report of tardigrades in Labrador, the mainland part of the Canadian

province of Newfoundland and Labrador. Seventeen species have been identified with a further

three species yet to be identified. It had been expected that the tardigrades found in Labrador

would overlap those of Greenland to the north, and of Newfoundland to the south, but the total

species count is much more similar to the latter (n= 26) than the former (n= 80). Two species

have been located in Labrador (Macrobiotus echinogenitus and Diphascon (Diphascon)

recamieri) which have not been recorded for Newfoundland although both are found elsewhere

in Canada. Proechiniscus hannae which had only been recorded for Western Greenland prior to

the Newfoundland study has now also been recorded for Labrador. Diphascon ramazzottii which

has previously been recorded for Europe and one location in Newfoundland was recorded in

Northern Labrador in very high numbers. Of the 31 species usually regarded as Arctic tundra

species only 12 have so far been recorded for Labrador suggesting that the tardigrade fauna is

somewhat depauperate for this region. Similarly of the seven heterotardigrades usually

associated with Arctic environments only one has been found in Labrador.



17

Origin and Diversification of the Arthropods: New Interpretations of Some

Old Characters Ruth Ann DEWEL1 and Jetta EIBYE-JACOBSEN2

1 Department of Biology, Appalachian State University, Boone, North Carolina, U.S.A. 2 Invertebrate Department, Zoological Museum, University of Copenhagen, Copenhagen, Denmark

Abstract. The large morphological gaps separating extant taxa such as onychophorans,

priapulids, and arthropods impede our ability to elucidate transitions that occurred in the early

evolution of these organisms. The successful closing of these gaps will depend on finding fossil

taxa, characters, and character states that can reveal critical steps in their evolution. However,

the identification and characterization of potentially informative characters in fossil taxa depends

in turn on understanding the structure, and if possible the development, of their putative

homologues in living organisms. Several characters exhibit diverse character states in fossil and

extant taxa and appear to be particularly useful in providing information on the early evolution of

the arthropods. One such character is the buccopharyngeal apparatus of tardigrades, which is

considered to have primary homology with portions of the “Peytoia” apparatus of Cambrian stem

group arthropods. Taxa bearing a “Peytoia” are found among lobopods, stem group arthropods

and euarthropods. The “Peytoia” apparatus is not considered to be homologous to the radially

symmetrical mouth and introvert of cycloneuralians, but to be a circumoral novelty that

incorporates at least one pair of limbs and surrounds a phylogenetically older mouth. The

buccopharyngeal apparatus, together with characters such as the arthropod labrum and biramous

limb, have been entered in a 44 taxa, 148 character phylogenetic analysis of primarily lobopod

and arthropod ecdysozoans. Characters for this analysis were defined broadly to include

previously unrecognized character states and have been described with explicit a priori

statements of putative homology



18

Genomic resources for the tardigrade Hypsibius dujardini

Jennifer DAUB, Fran THOMAS, Habib MAROON, Aziz ABOOBAKER, and Mark BLAXTER

Institute of Cell, Animal and Population Biology, Ashworth Laboratories, University of Edinburgh, Kings Buildings, Edinburgh, EH9 3JT, UK.

Abstract: We have begun a programme of comparative developmental biology utilising the

cultured tardigrade Hypsibius dujardini as a new model for examining evolution of core

developmental processes. Tardigrades are an attractive organism for comparative work because

of their basal position in the pan-Arthropoda, and the observation that they share some

morphological and developmental characteristics with other Ecdysozoa such as the nematodes

and arthropods. This small fresh water species can be cultured in the laboratory on an alga food

source Chlamydomonas reinhardtii, and produces ample material for embryology and life cycle

studies (see poster by Thomas et al.).

As part of our programme of research we are developing genomic resources for H.

dujardini. We intend to construct and screen both genomic and cDNA libraries to isolate genes of

interest for use in phylogenetic and developmental studies. Thus far, a mixed stage cDNA library

has been constructed and screened by the expressed sequence tag strategy. So far over 900 ESTs

have been generated which represent ~500 individual tardigrade genes. The nuclear genes

identified include both housekeeping genes (encoding ribosomal proteins, cytoskeletal proteins )

as well as important regulator genes (encoding 14-3-3 proteins, Hox B4, kinases ). In addition,

most of the mitochondrial protein- and rRNA-coding genes have been identified.

A preliminary analysis of the EST dataset will be presented. These ESTs will form the basis

of subsequent in situ expression screens and phylogenetic analysis.



19

The Ecological Distribution of Tardigrada in National Nature Reserve Stužica (Bukovské vrchy Mts , NE Slovakia )

Peter DEGMA and Miroslava PEČALKOVÁ

Department of Zoology, Comenius University , Bratislava , Slovak Republic Abstract. Ecological distribution of terrestrial tardigrades was studied in National Nature

Reserve Stužica (Bukovské vrchy Mts, East Carpathians ). Values or categories of fourteen

environmental variables were recorded during taking samples of mosses and lichens. Tardigrades

extracted from the samples were mounted in Hoyer's medium and identified using phase

microscopy. The data was statistically evaluated. A total of 4 780 specimens representing 33

tardigrade species (2 classes, 15 genera) were collected and identified from 150 samples. No

significant differences were found in tardigrade abundance from samples collected at different

underbeds. No significant regression was found between tardigrade abundance and sample

distance from upper substrate border. We came up with the same result of regression analysis

between the abundance of tardigrades and the position of mosses/lichens above ground level.

Only substrate thickness in case of presence and the sample distance from upper border of

substrate in case of quantity of different species were found as the significant gradient variables.



20

Three dimensional understanding of the buccal apparatus of Echiniscus viridissimus (Peterfi, 1956) (Echinisciodea, Tardigrada)

Jette EIBYE-JACOBSEN1 and Ruth Ann DEWEL2

1Invertebrate Department, Zoological Museum, University of Copenhagen, Copenhagen, Denmark 2Department of Biology, Appalacian State University, Boone, North Carolina, U.S.A. Abstract. Using a combination of Transmission electron Microscopy and Scanning electron

Microscopy a three dimensional understanding of the buccal cavity, the buccal tube and the

stylets of Echiniscus viridissimus is presented.

The foremost part of the buccal tube is continuous with the buccal cavity and the stylet

sheaths and forms what looks like an arrowhead structure. The stylets when protruded out

through the moth opening penetrate this structure and cross each other dorsoventrally. The

buccal cavity at this level is not spherical but is an s-shaped opening giving room for the

penetrating stylets and most probably guiding the direction of their movements.

The buccal tube connects the arrowhead structure and the lumen of the pharynx. SEM

preparations of the buccal tube from the related species Echiniscoides sigismundi (Schulze,

1865) reveal that the buccal tube is build from a great number of small spicule-like rods that are

held together by an organic matrix in the functioning organ. These rods fall apart when the

recently resynthesized organs in late simplex stage specimens are prepared. A close look at the

TEM sections from different levels of the buccal tube of Echiniscus viridissimus reveals that the

buccal tube of this species is also constructed from bundles of small spicule-like rods. SEM

preparations from other related species reveal that the surface of the buccal tube of members of

the genus Echiniscus is ridged. Information from TEM sections and the preparations of preactive

stadium specimens indicates that the buccal tube is constructed from bundles of spicule-like rods

throughout the entire genus. Additional evidence from TEM-sections of a simplex stadium

specimen of Actinarctus doryphorus Schultz, 1935 suggests that this conclusion might possibly

hold true for the entire class Heterotardigrada.

The stylets are seen to be hollow in the SEM preparations. Throughout their entire length

the stylets have a horseshoe shaped cross section that is open in the foremost part and forms a

second groove in the posterior part. Implications of these observations on the function of the

stylets are discussed.



21

Population Dynamycs of Dactylobiotus grandipes Schuster et al., 1977 (Tardigrada) in a Neotropical Eutrophic Pond

María L. FERNÁNDEZ1, Julio R. PELUFFO1 and María C. MOLY de PELUFFO1 1Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina.

Abstract. This work is a population study of Dactylobiotus grandipes (Schuster et al., 1977)

during an annual cycle in a eutrophic limnotope of the Neotropical region, i.e. the “Laguna Don

Tomás” ((36º37’ S, 64º18’ O; 177 above sea level), in the city of Santa Rosa (La Pampa,

Argentina). The tardigrades related to the periphyton were studied by means of monthly

sampling of small underwater stalks between February 2001 and January 2002. Density was

expressed as individuals per cm3 of substrate. The nutritional status of the populations was

identified, as well as the reproductive stage and molting condition. The size range of active

individuals was measured, both in the simplex stage and in those with developing eggs. The

population structure in terms of size class for each month was determined. The possible number

of molts was estimated and the presence of precystic, cystic and free egg stages was recorded.

Active individuals were found only during the April to September period, with a population peak

during May-June. D. grandipes exhibits seasonal trends in population dynamics, appearing in

autumn and disappearing in spring. They seem to survive seasonal changes by remaining at low

densities on the bottom and encysted on a substrate during the summer. Comparing the results

obtained with those of populations of D.grandipes in Lake Tahoe in North America, a similar

pattern of annual variation in water temperature can be observed. As to the individual size, the

southern population shows lower minimal values at hatching and lower still respect of the first

ecdysis, sexual maturity and maximum size. These differences could be related to differences in

the vital cycle favorable period and to differences in water temperature.



22

Encystment in eutardigrades: differences and common traits in two evolutionary lines

Roberto GUIDETTI, Deborah BOSCHINI, Lorena REBECCHI and Roberto BERTOLANI

Department of Animal Biology, University of Modena and Reggio Emilia, Modena, Italy. Abstract. Tardigrades have two forms of dormancy: cryptobiosis and encystment. The

encystment is a form of diapause known for a limited number of tardigrades and it is still little

studied. To increase the knowledge on encystment, two species of eutardigrades from Italy have

been considered: the moss-dwelling Amphibolus volubilis (Eohypsibiidae), able both to enter

cryptobiosis and to form cysts, and the freshwater Dactylobiotus parthenogeneticus

(Macrobiotidae), only able to form cysts. Cysts have been collected in nature or have been

induced under laboratory conditions. In the latter case, it was possible to follow the encystment

process phases. Cyst morphology has been analysed by LM, SEM and TEM. Two different

types of cyst have been found in A. volubilis, while in D. parthenogeneticus only one type. In all

three kinds of cyst, the encystment processes show both common and peculiar traits. Encystment

begins with the discharging of the sclerified parts of the buccal-pharyngeal apparatus, as in

ecdysis, but without the loss of the old animal cuticle. Then, two or three new cuticles are

serially synthesized, according to the type of cyst. In A. volubilis, the ultrastructure of these new

cuticles is similar to the active and unencysted animal cuticles while in D. parthenogeneticus the

new cuticles ultrastructure differs from that of the active and unencysted animals. A modified

buccal-pharyngeal apparatus, up to date undescribed, has been observed in one type of A.

volubilis cyst and in the D. parthenogeneticus cyst. The common traits lead us to suppose a

common origin of the phenomenon. These peculiarities may represent diversified adaptation

strategies to different environments which should be studied more in depth.



23

Dactylobiotus octavi n. sp. (Eutardigrada; Macrobiotidae) from Disko Island (Greenland)

Roberto GUIDETTI, Tiziana ALTIERO, and Roberto BERTOLANI

Department of Animal Biology, University of Modena and Reggio Emilia, Modena, Italy.

Abstract. During the "Workshop on Arctic tardigrades" at the Danish Arctic Station

(Qeqertarsuaq, Disko Island, Greenland) organized by R.M. Kristensen and his co-workers at the

end of the VIII International Symposium on Tardigrada (Copenhagen 2000), an undescribed

species of Dactylobiotus was found in freshwater sediments of the creek Isunngua. We had the

honour and the pleasure to describe this new taxon that we would like to dedicate to all

participants of that symposium, naming the species Dactylobiotus octavi n. sp. The animals look

similar to Dactylobiotus dispar and Dactylobiotus haplonyx for the presence of a very short

secondary branch in the claws of their first three pairs of legs, but they differ from these species

for their claw size and for their buccal tube width. This new species also has peculiar ornamented

eggs. The egg shell consists of open, crater-like processes connected up to the apex. This finding

increases the already high number of species found in Disko Island and once again underlines the

tardigrade importance in the biodiversity not only in that island, but in all the Arctic area. It also

confirms the peculiarity of some Dactylobiotus characters, which represents a very well defined

evolutionary line of macrobiotids developed in freshwater.



24

The “Hyena Female” within the Marine Tardigrada with the Description of Two New Species of Megastygarctides

(Arthrotardigrada: Stygarctidae) from Saudi Arabia.

Jesper Guldberg HANSEN and Reinhardt Møbjerg KRISTENSEN Invertebrate Department, Zoological Museum, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen Ø, Denmark Abstract. The Arabian Gulf of Saudi Arabia has a rich tardigrade fauna. The authors have

studied 22 small vials with tardigrades from the ARAMCO Northern Area Intertidal Sampling

Program in 1982. Eleven arthrotardigrades and one echiniscoid species were recorded from

seven intertidal stations. In this paper we described two new species of Megastygarctides. Slight

secondary sexual dimorphism is present in all species of the family Stygarctidae, but in one of

the new species, both the primary and secondary clavae have a different shape in the male than in

the female. Furthermore, the female has a unique genital structure. The genital ducts of the two

seminal receptacles are extended out of the body as two robust penile spines. The function of

these two structures, located lateral to the rosette-shaped female gonopore, is still mysterious, but

they may be involved in both copulation and in the insemination of the spermatozoa through the

eggshell. The name suggested for this type of female in tardigrades is the “tardigrade hyena

female”. The male has a typical heterotardigrade gonopore consisting of a small oval papilla with

a crescent-shaped opening. Another unique character of this species is the plate pattern.

Typically, the plates are dorsal in the Stygarctidae but in this species the plates completely

encircle the body. The other new species of Megastygarctides completely lacks dorsal plates,

which is very atypical in the family. The two new species are compared with the known species

of Megastygarctides and a revision of the genus is given.



25

A Study of the Genus Amphibolus from Disko Island, Greenland, with Special Attention on the Life Cycle of Amphibolus nebulosus (Eutardigrada: Eohypsibiidae)

Jesper Guldberg HANSEN1, Agnete Krabbe KATHOLM2 and Reinhardt Møbjerg KRISTENSEN1

1Invertebrate Department, Zoological Museum, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen Ø, Denmark

2 Department of Life Science and Chemistry, Roskilde University, Roskilde, Denmark

Abstract: In the last thirty years numerous investigations of the Disko Island tardigrade fauna

has been carried out from the Danish Arctic Station, Qeqertarsuaq, Disko Island, West

Greenland. The results have partly been obtained by scientific leaders of the Arctic Station and

partly from several field courses in Arctic Biology. At present, more than a hundred different

species of limnic/terrestrial tardigrades have been collected on the Disko Island. As part of a

field course in Arctic Biology, samples of mosses from four habitats were collected on Disko

Island, Greenland, in July 2002, in order to study the life cycle of Amphibolus nebulosus.

Additional material collected on Disko Island in the period 1976-2001 was examined for the

occurrence of Amphibolus species. The three species A. nebulosus, A. weglarskae and

Amphibolus nov. sp., are unequally distributed on the Disko Island at 24 locations. The

environmental preferences of A. nebulosus are apparently for wet habitats, as running or calm

water, for mud, soil and mosses, and for more dry environments as lichens. Based on these data,

it seems probable to consider A. nebulosus being hygrophilous and not a true hydrophilous

species. The environments preferred by A. weglarskae are drier (e.g. soil) than those preferred by

A. nebulosus. The two species are hardly ever found in the same substrate. Living in a range of

dry to moist habitats, it seems that A. weglarskae is a eurytopic species. Amphibolus nov. sp. is

probably a real hydrophilous tardigrade. It is found in permanent freshwater habitats like springs,

lakes and rivers. We found Amphibolus nov. sp. in aquatic mosses and algae in a heterothermic

pool, where we also found A. nebulosus. The study of Amphibolus nebulosus signifies that the

life cycle involves two types of cysts and two types of eggs. It seems that both kinds of cysts are

related to reproduction as well as to environmental changes. New information on the sclerified

structures, claws and the characteristics of the egg-shell within the genus are presented, and a

modification of terminology is suggested.



26

The response of soil-inhabiting tardigrade communities to various forests in the southern part of Kanagawa Prefecture

Hiroki HARADA1 & Masamichi T. ITO1

1Soil Ecology Laboratory, Graduate School of Environment and Information Sciences, Yokohama National University, Yokohama-city, Kanagawa, Japan Abstract. This study was carried out for the purpose of detecting the relationships between soil-

inhabiting tardigrade communities and various types of forest. Nine sites were selected in the

southern part of Kanagawa Prefecture. Vegetation types of these forests were: evergreen broad-

leaved forests (4 sites), deciduous broad-leaved forests (1 site), evergreen coniferous forests (3

sites) and citrus fruit orchard (1 site). In these sites, environmental factors (e.g. leaf litter dry

weight, soil pH, soil hardness, soil moisture content) were measured. For collecting tardigrades,

Baermann method was adopted. Tardigrades were identified in specific level by using a DIC

microscopy. Statistical analyses and multivariate analyses (CCA) were driven to know 1) species

diversity, 2) community similarity and 3) the correlation between environmental factors (23

series) and tardigrade faunal composition.

Tardigrade fauna was different among every forest sites, highest abundance (18,650 ind./m2)

and largest species number (26 species) was occurred in an artificial coniferous forest (site

“Nebu”).

Through this study, two main groups of tardigrades were distinguished. First group (M-group)

majorly contained Macrobiotus species, which is known as cosmopolitic species. Second group

(D-group) was formationed by genus Diphascon (e.g. D. nobilei, D. patanei, D. prorsirostre). As

remarkable fact, only Diphascon pingue was included to M group.

D-group was concentrated in the site “Nebu”. On the contrary, M group species were

dominant in other sites. From the result of CCA, distinct environmental factor could not be

decided, but the frequency of nematodes was recognized as main factor which influences D-

group existence.

Particularity of the site “Nebu” was also proved by statistical data, and this result doesn’t

correspond with large-scaled vegetational classification. It is sure that Nebu’s coniferous forest

created the unique environment for sustaining these special species (D-group). As a conclusion,

the forests should be evaluated not only by macroscopic factor, such as landscape, but by

microscopic organisms, such as tardigrade communities.



27

A Revision of the Marine Genus Orzeliscus, Arthrotardigrada, Tardigrada

Iben HEINER and Reinhardt M. KRISTENSEN

Department of Invertebrate Zoology, Zoological Museum of Copenhagen, Denmark, e-mail: [email protected] & [email protected] Abstract. Du Bois-Reymond Marcus described the marine genus Orzeliscus with the species

belopus in 1952 from the island of São Sebastião in Brazil. In 1953 Schulz described

septentrionalis, which was synonymized with belopus in 1980 by Pollock.

Over the years different scientists have reported several findings of the genus Orzeliscus from

several other countries, e.g., France, New Caledonia, Bermuda, Scotland, the Virgin Islands and

the Galapagos Islands. The large collections in the Zoological Museum of Copenhagen,

Denmark include several specimens from France, Egypt, Japan, Bermuda, Tobago, USA and

Australia. Close examination of them has revealed the presence of several new species, e.g., a

new species from Japan with a protruding mouth cone and one from Egypt which is

hermaphroditic. The characteristics of these new species will be presented together with a

revision of the genus. The specimens from Queensland, Australia consist of three species, one of

which has only three toes on the each leg and lateral projections on the body with long pillars.

On the basis of these new characters a new genus has been established and the family

Orzeliscidae is rediagnosed. A map of the world distribution of the family with all known

records is also included.



28

Tardigrades and Biomimetic Cell Stabilization

Richard F. HELM, Karsten KLAGE and Malcolm POTTS

Department of Biochemistry and Virginia Tech Center for Genomics, Virginia Tech, Blacksburg, Virginia USA

Abstract. The ability of tardigrades to withstand a wide variety of environmental insults has

been a source of awe as well as a direction of scientific inquiry since their initial description by

Van Leeuwenhoek in 1702. As they are considered one of the most resilient animals on the

planet, we are interested in understanding their metabolic biochemistry and cell biology with the

long term vision of applying similar strategies to the preservation of cells and cell components of

biomedical importance. Our present efforts focus on strategies to monitor the 3 major “-omes,”

namely the transcriptome, proteome and metabolome as tardigrades undergo desiccation and

rehydration. An overview of our research goals will be presented from the perspective of

understanding the biochemical control of cryptobiosis and its effects on cell biology and

metabolism.



29

Seasonal and Spatial Variation in Tardigrade Diversity in Leaf Litter from Florida and Louisiana

Juliana HINTON, Harry A. MEYER, Kathleen TRAHAN

Department of Biological and Environmental Sciences, McNeese State University, Lake Charles, Louisiana, U.S.A.

Abstract. During 2002-2003, we collected leaf litter core samples (10cm diameter) from each of

two sites in southwestern Louisiana and one site in central Florida. A mixture of deciduous

leaves and pine needles characterized the Florida site and one of the Louisiana sites; the leaf

litter of the other Louisiana site was composed almost entirely of needles. In Louisiana, cores

were collected at four times: summer, fall, winter, and spring. Florida cores were only collected

in winter and spring. Four cores were collected for each combination of site and date. Each core

was divided into two layers, an upper leafy layer (1-2cm in depth), and a lower layer of humus

(1-2cm in depth). Five species of tardigrade were found in Louisiana material and three in

Florida. Within each site, there was wide variation in tardigrade diversity among samples and

dates. Among the three sites, tardigrade species richness and abundance declined with the

proportion of the material made up of needles. Tardigrade diversity at these sites in Florida and

Louisiana is considerably lower than that previously reported in leaf litter and humus samples

from beech forests in Italy and Tennessee.



30

The Effects of Prehydration on Anhydrobiotic Survival in the Tardigrade Milnesium tardigradum

Daiki D. HORIKAWA1, Wataru ABE2, and Seigo HIGASHI1

1Division of Biosciences, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Japan.

2Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo, Japan Abstract. It has been thought that the high humidity prior to rehydration with water ensures the

revival of anhydrobiotic animals. For example, it is known that placing anhydrobiotic nematodes

directly in water at lower relative humidity causes decreased survival. However, there are little

reports on the effects of prehydration on tardigrades. In the present study we estimated the

effects of relative humidities on the recovery of the tardigrade Milnesium tardigradum from its

anhydrobiotic state. The tardigrades were dried at 80% RH for 24 hours, and transferred to 0%

RH air for 72 hours before prehydration at various relative humidities (0, 25, 84 or 97%) for 24

hours. Then animals were rehydrated with water and showed high survival rates under all the

conditions, indicating that this xerophilous tardigrade species does not require any prehydration

when the animals revive from anhydrobiosis and is more tolerant to the rapid rehydration than

other anhydrobiotic animals.



31

Tardigrades in six phorophytes of the moss Calymperes tenerum C. Müller

Javier JEREZ - JAIMES1

1Department of Biology, University of Puerto Rico, Mayagüez, Puerto Rico, U.S.A.

Abstract. The composition of tardigrade communities on the Mayagüez Campus of the

University of Puerto Rico was studied from January through May 2003. Eleven trees of six

phorophytes species were selected for the moss Calymperes tenerum: (Calophyllum brasiliense

(2), Swietenia macrophylla (2),Bucida buceras (2),Hymenaea courbaril(1), Mangifera indica (2)

and Ptychosperma elegans (2). During the dry season (January- March) and the rainy season

(April-May) five samples of four cm2 each were taken from each tree. Tardigrades were

extracted from the samples, mounted individually in Hoyer’s medium, and identified to species

using phase and Nomarsky microscopy. Differences in tardigrade community composition were

founded among and within phorophyte species. Swietenia macrophylla and Mangifera indica

were the phorophytes of the moss C. tenerum with the greatest number of species and abundance

of tardigrades.



32

Milnesium katarzynae sp. nov., a new species of eutardigrade (Milnesiidae) from China

Łukasz KACZMAREK1, Łukasz MICHALCZYK2 and Clark W. BEASLEY3

1Department of Animal Taxonomy & Ecology, Institute of Environmental Biology, A. Mickiewicz University, Szamarzewskiego 91 a, 60-569 Poznań, Poland; e-mail: [email protected]. 2Institute of Environmental Sciences, Jagiellonian University, Ingardena 6, 30-060 Kraków, Poland; e-mail: [email protected]. 3Department of Biology, McMurry University, Abilene, Texas 79697, U.S.A; e-mail: [email protected]. Abstract. A new eutardigrade, Milnesium katarzynae sp. nov. is described from two moss

samples collected by Katarzyna Ratyńska in China (Nature Reserve near Kangding) in August

2002. Until now only 5 species of the genus Milnesium Doyere are known: Milnesium

brachyungue Binda & Pilato, Milnesium eurystomum Maucci, Milnesium slovenskyi Bertolani &

Grimaldi (known only from Cambrian amber), Milnesium tardigradum Doyére and Milnesium

tetralamellatum Pilato & Binda. This new species differs from other described members of genus

in having fine (0.5 – 1.0 µm) reticular design on the dorsal side of the body (better visible in the

caudal region), lacking of eyes, and having claws in the almost same size on all legs. M.

katarzynae sp. nov. is similar to specimens of M. tardigradum from New Zealand which have

reticular “shallow depressions” in cuticle but is clearly different by lacking of eyes and narrower

buccal tube (pt = 24.8-29.6 in new species and pt = 41.9 in the specimens collected in New

Zealand).



33

Tardigrades – understanding desiccation tolerance

Karsten KLAGE1, Richard F. HELM1, Jonathan D. EISENBACK2, Ruth DEWEL3, Roberto

BERTOLANI4 and Malcolm POTTS1

1Department of Biochemistry and Virginia Tech Center for Genomics, Virginia Tech, Blacksburg , Virginia 24061 2Department of Plant Pathology, Physiology and Weed Science, Virginia Tech, Blacksburg , Virginia 24061 USA 3 Department of Biology, Appalachian State University , Boone , North Carolina 28608 USA 4 Department of Animal Biology, University of Modena and Reggio Emilia, 41100 Modena , Italy Abstract. Some species of tardigrades have the ability to survive long periods of complete

dryness assuming a physiological state known as ‘tun’. It was shown that in this dry stage the

tardigrades are able to resist diverse and extreme environmental conditions, such as low and high

temperature (-195°C to 110°C), ionizing radiation, vacuum, high pressure (6000 times

atmospheric) and long periods of dryness (up to eight years). However, by adding water to the

dried organisms, they regain normal vitality with apparently no damage to cell organelles or cell

structure. How can proteins, DNA, lipids, sugars, etc. withstand this water loss, without

precipitating or denaturing, and what are the mechanisms that permit the tardigrade to survive

complete dryness? Early work with tardigrades, and other desiccation tolerant organisms such as

the brine-shrimp (e.g cyst of Artemia salina), lead to the development of the “water replacement

hypothesis,” which describes how the non-reducing disaccharides, trehalose and sucrose, replace

hydrating water molecules lost during desiccation. Later the hypothesis was modified through

incorporation of the “glassy state theory”. Sugars and proteins like LEA create a ‘glass’ during

dryness and provide stability and help maintaining cell integrity. Also emphasis was put on the

potential role of amphiphiles. Using molecular and biochemical methods our laboratory is

focusing on the mechanisms used by tardigrades to achieve desiccation tolerance. These include

differential expression of mRNA, proteome analysis through mass spectrometry, electron

microscopy, and analysis of sugars and lipids.



34

Extreme Secondary Sexual Dimorphism in The Genus Florarctus (Arthrotardigrada: Halechiniscidae)

Reinhardt Møbjerg KRISTENSEN

Invertebrate Department, Zoological Museum, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen Ø, Denmark Abstract. Secondary sexual dimorphism in florarctid tardigrades is well known. The males are

usually smaller than the female, and the primary clavae are relative longer in the males. A new

species of Florarctus from coralline sand collected subtidally just behind the reef fringe of Long

Island, Chesterfield Reefs (Pacific Ocean) has extreme secondary dimorphism. The male has

developed clavae that are much thicker and three times longer than in the female. Furthermore,

the clava of the male is formed as an accordion-like structure. This structure is not seen in the

female where the clava is smooth. Ten other species of Florarctus were investigated from the

Pacific Ocean. The male was always smaller than the female, but the male of the F. heimi and

the female of F. cervinus have not been recorded. The description of F. heimi date back to 1965

and that of F. cervinus is from 1987. Renaud-Mornant described these two species from New

Caledonia and her large collection was reinvestigated in the present study. In the Australian

summer (December 1995) large populations of Florarctus species were found subtidally in Shark

Bay, Heron Island, and the Great Barrier Reef. F. heimi and F. cervinus were found together in

coralline sand from Heron Island. The animals were kept alive and video-taped in the laboratory

of Queensland Museum. All specimens of the very large F. heimi (about 400 µm) were females

and all specimens of the smaller F. cervinus (about 170 µm) were males. The differences in the

caudal expansion between the two “species” were exactly as in the two excellent original

descriptions. Males of F. cervinus were observed to mate with females of F. heimi. Observations

of mating in Arthrotardigrada are rare. Only one observation of Parastygarctus sterreri has been

made. As in P. sterreri the floractids mate venter to venter. The conclusion based on the

observations on animals from Heron Island is that F. cervinus is a junior synonym of F. heimi.

Florarctus cervinus is the male of F. heimi and this is the first time that such an extreme sexual

dimorphism has been observed in tardigrades.



35

Preliminary Results from a Study on Ecuadorian Tardigrada.

Nigel J. MARLEY School of Biological Sciences,University of Plymouth, Drake Circus, Plymouth, PL4 8AA,United Kingdom . Abstract. There are very few published studies on the tardigrade fauna of Ecuador. Preliminary

results from an altitudinal survey of moss and lichen inhabiting tardigrades from the Volcán

Chiles, Ecuador are presented.

Sixteen operational taxonomic units have been found so far. Precise identifications, particularly for

eutardigrades, has been difficult due to problems accessing literature on South American taxa. One

species new to science is described, Platicrista ramsayi.



36

Designation of Pseudobiotus kathmanae Nelson (Tardigrada) as the type species of Pseudobiotus Nelson.

Nigel J. MARLEY1, Roberto BERTOLANI2 & Diane R. NELSON3

1 School of Biological Sciences,University of Plymouth, Drake Circus, Plymouth, PL4 8AA , United Kingdom . 2 Dipartimento di Biologia Animale, Università di Modena e Reggio Emilia, Via Campi 213/d, 41100 Modena, Italy. 3 Department of Biological Sciences, East Tennessee State University, Johnson City, TN 37614 ,USA Abstract. The contents of the application to the International Commission on Zoological

Nomenclature, Case 3017, are presented with an explanation of how its publication fell between

the third and fourth editions of the Code of Zoological Nomenclature. The aim of the application

was to ask the Commission to designate a new type species for Pseudobiotus Nelson, following

the discovery of the misidentification of the original type. The full publication of case 3017 was

then delayed until all papers relevant to the application were published: Nelson, Marley and

Bertolani (1999) and Bertolani, Marley and Nelson (1999). These two papers were also presented

at the 7th International Symposium of the Tardigrada held in Düsseldorf, Germany. The case was

then held by the Commission pending the publication of the fourth edition of the Code because

of relevant changes to Article 70. The fourth edition of the Code came into affect on January 1st

2000 . Case 3017 then became unnecessary for the Commission to see and was left unpublished

and without an Opinion ruling from the Commission. This has resulted in Pseudobiotus Nelson

having no designated type. To rectify this situation the details of Case 3017 are briefly present

here and then, with the reference to the appropriate articles of the fourth edition of the code, a

new type is designated for the genus.



37

Tardigrades of Southwest England, United Kingdom. A long term, multi-habitat survey from the coastal urban habitats to the upland Moors.

(Short title: Bear Hunting in Devon)

Nigel J. MARLEY

School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth, PL4 8AA , United Kingdom .

Abstract. The tardigrade fauna of southwest England has been poorly reported. A long term, low

intensity survey has been carried out across the region. Samples have covered a wide range of

habitats including rocky intertidal, deciduous woodlands, acid moorlands and urban xeric.

Sample materials have included seaweed, marine sediments, barnacles, bryophytes, lichens, leaf

litter and bark. The results from this wide ranging survey are presented with many new additions

to the local and national fauna being reported. One species new to science is described from the

coastal urban habitats. The distribution of individual species and different tardigrade

communities is discussed and related to bedrock type and water regime.



38

Adult and Embryonic Anatomy of Hypsibius dujardini

Habib MAROON, Aziz ABOOBAKER, Fran THOMAS, Jennifer DAUB, and Mark BLAXTER Institute of Cell, Animal and Population Biology, Ashworth Laboratories, University of Edinburgh, Kings Buildings, Edinburgh, EH9 3JT, UK.

Abstract. To gain a deeper understanding of the evolution of the Ecdysozoa (a superphletic

grouping of moulting animals including nematodes and arthropods), we have recently initiated

research into tardigrade biology using a a cultured Eutardigrade: Hypsibius dujardini (see

abstract by Thomas et al.). We aim to use this species to study tardigrade development to further

our understanding of the evolution of developmental processes that have been studied deeply in

arthropod and nematode model systems. Here we describe progress on the characterisation of the

embryonic and adult anatomy of Hypsibius dujardini. We are developing methods to introduce

vital and other stains into live and fixed animals. Currently we are able to stain juveniles and

adults reliably, but embryos are relatively diffcult to stain (presumably because of permeability

barriers in the egg). DAPI staining of nuclear DNA reveals cell number in the different organ

systems of adults. Phalloidin, a stain that binds to actin cables, displays the musculature of the

adult. Bodipy-Fl-Ceramide, a membrane-associated fluorescent marker, has been used to show

the nervous system. We have also undertaken light and fluorescent microscopic studies of

embryonic development confirming some previous observations (Eibye-Jacobsen.1997). DAPI

staining has also been of some use for investigating embryonic development. We are currently

endeavouring to define suitable protocols for permeabilisation of the chorion,

immunohistochemistry, and for in situ hybridisation.



39

A Comparative Study of Southern Indiana Urban and Rural Tardigrade Populations Due to Seasonal Environmental pH Changes

Clayton MARSHALL

Eastern High School, Pekin, IN Abstract. Tardigrades are invertebrates that are used as an environmental bio-indicator.

Problems with acid precipitation are occurring across America’s Northeast region. Coal burning

plants along the Ohio River Valley are a suspected cause of these problems. The purpose of this

research project was to determine the effect of environmental pH on tardigrade populations

collected from lichen samples on urban and rural limestone monuments in Southern Indiana. It

was hypothesized there would be a positive correlation between environmental pH and

tardigrade community structure. Testing sites were selected from six urban and six rural areas in

Southern Indiana, and four tests were conducted during each of the four seasons resulting in a

total of 96 samples collected. Lichen samples were placed into distilled water, and tardigrades

were extracted, counted, and preserved. The pH of each sample was then measured. Tardigrades

were later mounted on glass slides and were identified as the following species: Milnesium

tardigradium, Echiniscus perviridis, Echiniscus viridis, Echiniscus cavagnaroi, and Echiniscus

knowltoni. The 12-month urban pH mean was 7.25 with a total tardigrade population of 96. The

12-month rural pH mean was 7.07 with a total tardigrade population of 1292. The deviation of

pH from neutral was statistically analyzed using a t-test and was determined to be highly

significant at the 4 x 10-6 level. The correlation between pH and tardigrade population density

was statistically analyzed using linear regression and was determined to be significant at the 0.01

level. Based on the data collected the hypothesis was supported.



40

Exceptional, Tardigrade Dominated Ecosystems in Ellsworth Land, Antarctica

Sandra J. MCINNES and Peter CONVEY

British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK

Abstract. We describe an exceptionally simple terrestrial faunal community present on inland

nunataks of Ellsworth Land, Antarctica, at locations between Sky Hi and Haag Nunataks (c. 75 -

77°S 70 - 73ºW). No biological studies have previously been made at these latitudes in the

Antarctic Peninsula (West Antarctic) region. Samples obtained from a series of isolated

mountain groups indicate a common fauna dominated by Tardigrada, with a minority component

of Rotifera. The fauna is exceptional in its simplicity, including 6 tardigrade species (1-2 new to

science) and two trophic levels. Neither nematode worms, the most important element of the

simplest communities previously reported worldwide (from the Ross Sea Dry Valley region of

continental Antarctica), nor microarthropods, otherwise represented in all known Antarctic

terrestrial communities, are present. The community shows closer affinities with continental

Antarctic tardigrade communities, with which it shares three species, than the maritime zone,

sharing only two pan-Antarctic species with the latter. The remaining four species form a group

that is unique to Ellsworth Land, and may suggest its prolonged existence as a distinct

biogeographical unit.



41

Tardigrade fauna of Sub-Antarctic Marion Island in the Prince Edward Archipelago, South Indian Ocean – a Preliminary Report.

Sandra J. MCINNES

British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK Abstract. Sub-Antarctic Marion Island (46°54’S; 37°45’E) one of the islands in the Prince

Edward Archipelago, South Indian Ocean, is a c. 4 million years old shield volcano, with the

remnants of a summit Pleistocene glacial ice cap. A survey was carried out in April 2003 to

identify the tardigrade species diversity and habitat preferences of the fauna on this island.

Limno-terrestrial tardigrades were sampled from a range of terrestrial habitats that included

moss, lichen, soil and cushion forming higher plants. Freshwater habitats were sampled from

shallow shelf regions and marine tardigrades collected from the coastal shorelines. Collections

focused on specific terrestrial habitats and produced several new records for the island and new

species.

The tardigrade records from this study represent the first detailed reports from Marion Island,

and are to be compiled into a database with three primary objectives; 1) elucidate the

biodiversity of sub-Antarctic Marion Island tardigrades; 2) identify ecological, in particular

substrate association, of the limno-terrestrial fauna; and 3) associations with other co-occurring

meiofauna.

The limited earlier references to tardigrades on Marion Island placed the island group in the

biogeographic sub-Antarctic cluster. This new study adds more detail to the biogeography of the

tardigrades in this sector, and forms one of the baseline studies on the meiofauna of Marion

Island.



42

Tardigrade fauna of the South Sandwich Islands

Sandra J. MCINNES and Peter CONVEY British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK Abstract. Sub-Antarctic South Sandwich Islands comprise a group of islands of volcanic origin

between the latitudes of 56º 18'S, 27º 34'W and 59º 27'S, 27º 22'W. All the islands are of recent

origin with many still exhibiting some form of volcanic activity from warm ground and hot lakes

to smoking fumaroles. The islands are part of a crustal upwarp extending from South Georgia

through the South Sandwich Islands to the South Shetland Islands that connects the Andean

chain of South America to the Antarctic Peninsula.

These islands were part of an extensive survey during 1997, covering vegetation and meiofauna.

The tardigrade fauna shows a limited biodiversity, in keeping with the recent formation of these

islands. However, there is an indication that the source of the fauna is from both sub-Antarctic

and Antarctic origins.



43

Distribution of Terrestrial Tardigrades in the State of Florida

Harry A. MEYER Department of Biological and Environmental Sciences, McNeese State Universit , Lake Charle , Louisiana, U.S.A Abstract. The distribution of terrestrial tardigrades in the state of Florida is poorly known.

Published records from the state include only two species, Echiniscus perarmatus and E.

virginicus, both from the northeastern part of the state. I collected samples of moss, lichen, and

liverwort from all 67 Florida counties during 2002-2003. These samples were primarily taken

from trees and fallen branches. Where possible, I chose sampling sites in the relatively

undisturbed wooded areas of state and national parks. However, a large portion of the Florida

landscape has been heavily impacted by agriculture, forestry, and urban development. Therefore,

the sampling sites in many counties were in highly disturbed habitats (rural roadsides,

cemeteries, municipal parks, urban neighborhoods, etc.). Where possible, lichens, mosses, and

liverworts were identified (27 species). The number of tardigrade species per sample ranged

from one to four. In all, sixteen tardigrade species, including E. virginicus, were found in the

state. The most commonly detected species were Milnesium tardigradum, Macrobiotus

echinogenitus, and Minibiotus intermedius. Echinscids and non-Macrobiotid species of the Order

Parachela were relatively uncommon. Suitable tardigrade habitat was difficult to locate in much

of the central and southern regions of the state, especially in pine forests, the Everglades , and the

Florida Keys . Tardigrade species richness and abundance also appeared to be lower in these

areas. Preliminary results from a similar, as yet uncompleted, survey of Louisiana suggest that

tardigrade diversity may be lower in Florida than in Louisiana.



44

Small-scale Spatial Variability in Terrestrial Tardigrade Populations

Harry A. MEYER Department of Biological and Environmental Sciences, McNeese State University , Lake Charles , Louisiana , U.S.A. Abstract. Terrestrial tardigrades commonly occur in the lichens and mosses that occur on trees

and rocks. Although tardigrades in these habitats are often said to be very patchy in their

distribution, this assessment has not often been backed by quantitative sampling. In this study I

assess spatial variability in tardigrade populations inhabiting small patches (1-45mm diameter)

of moss and lichen on trees and rocks. In 2002 I collected tardigrades from four replicate rocks in

the Ouachita Mountains of Arkansas, U.S.A. I collected 30 lichen patches on two rocks and 20

moss patches on two others. In Lee County, Florida I collected tardigrades from lichen patches

on two neighboring Royal Palm Trees. The tardigrades in each sample were mounted and

identified and the numbers of bdelloid rotifers, nematodes, and mites recorded. The variation

among lichen or moss patches within rocks or trees was very high; the only consistent patterns

were that very small patches usually lacked tardigrades, and the predatory species Milnesium

tardigradum tended to be most abundant in larger patches. Tardigrade diversity abundance also

varied greatly within sites when lichens and mosses of the same species were compared from

different rocks and trees (in the most extreme case, comparing the two Royal Palms, one tree had

numerous individuals of three tardigrade species present while the other had no tardigrades at

all). The results of this quantitative sampling support the assertion that tardigrades are very

patchy in distribution. Given the considerable time investment required for the quantitative

processing of such samples, this high spatial variability in tardigrade diversity and abundance

may make them unsuitable for rigorous quantitative testing of ecological hypotheses.



45

Auto-Montage Imaging for Tardigrades

William R. MILLER1 and Zephyr H. JOHNSON2

1Department of Biology, Chestnut Hill College, Philadelphia, PA, U.S.A. 2Biodiversity Division, Academy of Natural Sciences, Philadelphia, PA, U.S.A. Abstract. Advances in computer-aided microscopy are going in many directions today and

many of us have discovered digital imaging to be very useful for references, measurements, and

comparisons. Because tardigrades are three-dimensional we understand the depth of field

limitations imposed by the physics of magnified light. When using a microscope we overcome

the issue by continually focusing. When we take a picture or image we are limited to the one

layer in focus and the out of focus material around our area of interest may render an image

useless. The Montage concept seems to show real some promise for tardigrades. For transparent

and three-dimensional specimens Montage imaging appears to be able to produce a clearer image

with more detail in focus than conventional or digital photography. The idea is to take a series of

digital images as layers while focusing down through the specimen. In practice, the operator

identifys the top and bottom of the specimen, selects the number of layers to be imaged, and tells

the computer to take the images. The computer controls a stepper motor that moves the focus a

fraction of a millimeter, takes an image of the layer, and moves again. Each layer image is

stored as digital data and can be viewed individually or assembled by the computer according to

an algorithm into a montage image. The montaging process analyzes each layer and erases any

part of the image that is not within the depth of field range and sharply focused. Then the

montage image is assembled using only that part of each layer that is in focus. The result is a

very three-dimensiona, in focus image that should be most useful in tardigrade taxonomic work.



46

Tardigrades of the Sub-Antarctic: 5000 year old eggs from Marion Island

William R. MILLER1 and Harold F. HEATWOLE2

1Department of Biology, Chestnut Hill College, Philadelphia, PA, U.S.A. 2NorthCarolina State Universtiy, Realigh, North Carolina, U.S.A. Abstract. During the examination of pollen analytical samples taken from two peat bogs on Sub-

Antarctic Marion Island, tardigrade eggs were recognized. Samples from two sites at Albatross

Lakes and Kildalkey have yielded over 500 eggs of four different species of tardigrades. The

samples were radiocarbon dated in the original research and date as far back as 7300 years before

present. At the 5000-year level, tardigrade eggs appear in the samples. Cores of peat bogs

represent a record of the history of vegetation and animal change or stability over time. Using

the assumptions developed by pollen researchers that the debris that settles onto the bog is in

proportion to its content in the atmosphere, which is in proportion to its concentration at its

source. We suggest a similar model for tardigrade populations.



47

Tardigrade Distribution in a Medium-sized City of Central Argentina

María C. MOLY de PELUFFO1, Julio R. PELUFFO1, Alejandra M. ROCHA1 and Irene L. DOMA1. 1Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina. Abstract. The distribution and abundance of tardigrades in the city of General Pico (35º40' LS;

63º44' LO) – Argentina – are analyzed from samples taken during autumn and spring 2001.

Sampling sites included paved urban locations with different traffic intensities, non-paved

periurban places with abundant suspended dust, and places with peculiar conditions such as the

city industrial area and the bus station. Trees of the same species were selected in each area and

from each of them nine circular samples of moss and/or lichen were taken with an 11 millimeter

diameter sampling tool. The diversity, density and relative abundance of tardigrades was

recorded. Species richness varied from 1 to 4. The species recorded were: Echiniscus rufoviridis,

Milnesium tardigradum, Ramazzottius oberhaeuseri, Macrobiotus areolatus and an undescribed

species of the family Macrobiotidae. R. oberhaeuseri and M. tardigradum were the most

frequent species. R. oberhaeuseri dominates in periurban areas with high suspension dust and

very exposed to the sun. This agrees with the known higher resistance to drought of R.

oberhaeuseri. M. tardigradum dominates on paved streets with intense vehicle traffic. M.

areolatus and Macrobiotidae sp. are uncommon, but wherever present they are the dominant

species. E. rufoviridis appears in only a few samples and always very few specimens. In a site

placed near a lead polluting operation (battery factory), only two specimens of tardigrades were

found. Results support the hypothesis of a relationship between the air quality and the

lichenophile meiofauna.



48

Tardigrade Community Composition in four forest types in the El Diviso Reserve, (Santander, Colombia)

Eliana X. NARVAEZ1 and Javier JEREZ - JAIMES.1

1Department of Biology, University of Puerto Rico , Mayagüez ,Puerto Rico, U.S.A.. Abstract. A survey of the community composition and distribution of bryophilous tardigrades in

the “El Diviso Reserve,” Santander (Colombia), was conducted during the time period from

March 1999 through February 2000. Four forest types were chosen, old pine forest (Pinus

patula) with secondary forest at 1800 m, cypress forest (Cupressus lusitanica) at 1850 m, pine

forest at 1970 m and primary Sub-Andean forest at 2100 m. In each forest a plot or transect of

200 m2 was used and all trees present were sampled. Tardigrades were extracted from the

samples, mounted individually in Hoyer's medium, and identified to species using phase

microscopy. Variation with altitude and in composition were determined. In El Diviso Reserve

tardigrades were present belonging to 2 classes, 8 genera, and 15 species

(Calohypsibius verrucosus, Hypsibius arcticus, H. dujardini, Isohypsibius prosostomus,

Itaquascon bartosi, Pseudechiniscus novaezeelandiae, Macrobiotus areolatus, M. harmsworthi,

M. hufelandi, M. islandicus, M. cf. occidentalis, M. richtersi, Minibiotus intermedius, and

Milnesium tardigradum). Differences in tardigrade community composition and altitudinal

variation were found. The cypress forest had the highest richness and diversity values. The

cypress is an introduced species that turned out to be a good phorophyte for mosses and

tardigrades.



49

Long-term anhydrobiotic survival of lichen-dwelling tardigrades

Lorena REBECCHI, Roberto GUIDETTI, Simona BORSARI, Tiziana ALTIERO, and Roberto BERTOLANI

Department of Animal Biology, University of Modena and Reggio Emilia, Moden, Italy.

Abstract. It is not rare to find in references that anhydrobiotic tardigrades can survive for more

than a century. However, a closer look at the empirical evidence provides very little support that

tardigrades are capable to survive dried for such a long time, suggesting that 7-8 years may

represent the limit of cryptobiotic survival (Jönsson and Bertolani: J. Zool. London 2001, 255:

121-123; Guidetti and Jönsson: J. Zool. London 2002, 181-187). In addition, the available data

derived from limited experiences in which statistical analysis was not applied to verify the

recovery rates. In order to fill this gap, we carried out a study to evaluate the long-term survival

of naturally dried tardigrades. A large fragment of dry lichen (Xanthoria parietina) was collected

in field after two days from rain in 1999. The dry lichen was stored inside a paper bag in

laboratory at room conditions with registered humidity and temperature. Four weighed replicates

of lichen were rehydrated after various lengths of storage, all tardigrades extracted and the

survivors enumerated. Five species of tardigrades were found, but two of them only occasionally.

Ramazzottius oberhaeuseri and Echiniscus spp. were sufficiently represented for statistical

analysis. At the beginning of the experiment a percentage of R. oberhaeuseri (8.9%) and of

Echiniscus spp. (28.3%) did not survive. A significant decrease in recovery of R. oberhaeuseri

was observed after 86 days. Echiniscus spp. survived up to 1082 days, while R. oberhaeuseri still

has 21.7% of survival after 1192 days. In addition, in R. oberhaeuseri, significant intraspecific

differences in survival rate were found in relationship to the animal age, moulting and female

gonad stage. A recovery after four years of anhydrobiosis should be considered a long-term

survival, important from an ecological and evolutionary point of view. A wider knowledge of

cellular and molecular mechanisms allowing this longevity may find biotechnological

perspectives.



50

Resting eggs in tardigrades

Lorena REBECCHI, Giorgia RINALDI, and Tiziana ALTIERO Department of Animal Biology, University of Modena and Reggio Emilia, Modena, Italy

Abstract. Dormancy includes both diapause and quiescence. These phenomena are respectively

under endogenous and exogenous control. Both dormancy forms occur in tardigrades.

Nevertheless, only some species of tardigrades are able to carry out both quiescence

(cryptobiosis) and diapause (encystment). Little is known on egg dormancy in tardigrades, apart

their possibility to survive dehydrated. Current literature rarely refers on the production of two

different kinds of eggs in the same species. In particular, thin-shelled and thick-shelled eggs were

identified only in few cases. According to some authors, thick-shelled eggs are produced when

environmental conditions are unfavourable. Our analysis of life history traits of a reared strain of

Macrobiotus richtersi evidenced that hatching phenology is spread in about 90 days. As a

consequence, we carried out a research on the eventual presence of resting eggs in M. richtersi,

using an apomictic triploid cytotype. We have utilized the first oviposition in lab of females

sampled in nature in spring and in the fall, and eggs from several generations of different clones

reared in lab. All the laid eggs were maintained in water up to the eventual hatching. About 90%

of hydrated eggs hatched, with a time of development ranging from a minimum of 30 days to a

maximum of 62 days. The eggs unhatched after 90 days have been observed at LM, dried,

maintained dried for 21 days and then rehydrated. Seventy-three (9.4%) eggs did not hatch and

were then dehydrated. Nine of them, most of which with a completely formed animal inside,

hatched after rehydration. Therefore, in this species subitaneous and resting eggs are present. The

last ones need a cue to hatch, suggesting that another form of diapause may be possible in

tardigrades. This represents a further strategy to colonize and inhabit unpredictable

environments.



51

Tardigrades of North America: Southeastern Pennsylvania, U.S.A.

Diana SUCHARSKI1 and William R. MILLER1

1Department of Biology, Chestnut Hill College, Philadelphia, PA, U.S.A. Abstract. A general survey of tardigrade habitats was conducted through out southeastern

Pennsylvania during the spring and summer of 2003. The collections included moss, lichen, soil,

litter, and water at each site if available through out the southern part of the Delaware River

watershed. Each location was recorded with global positioning systems for Geographical

mapping. The substrate, habitat, and exposure was recorded for each sample. Tardigrades,

rotifers, and nematodes were counted. Tardigrades were extracted by soaking, mounted in

Hoyer’s medium and identified to species. The collection was analyzed for patterns and

relationships between and among species of tardigrades, between the other animals, their

habitats, and substrates. Present in Southeastern Pennsylvania were tardigrades of 2 classes, 8

genera, and 14 species. Significant patterns of association were detected between species of

animals and specific habitats. The patterns have been compared spatially with human

demographic patterns.



52

Oogenesis of Milnesium tardigradum

Atsushi C. SUZUKI

Department of Biology, University of Keio, Hiyoshi,Yokohama, Japan Abstract. A parthenogenetic strain of Milnesium tardigradum has been maintained since

autumn 2000. These animals were fed on a monogonont rotifer and grew into mature adults at

the 3rd-instar stage. The first period of egg laying accompanied the third moult. The egg-laying

/moulting intervals of adult animals were around 6-10 days. The life history of M. tardigradum

under the rearing environment included up to seven periods of moult or five times of egg laying.

The number of eggs in a clutch varied according to the nutritional condition of the mother and

ranged from 1-12 eggs/clutch. It is an interesting problem how the number of eggs is decided. In

this study, the internal structure of ovary was morphologically investigated to elucidate the

relationship of oocytes and other ovarian cells. Specimens from immature larvae and adults with

various stages of ovaries were fixed in glutaraldehyde and embedded in Epon. Semithin and

ultrathin sections of these specimens were observed by light microscopy and transmission

electron microscopy, respectively, and fine structures of the ovarian cells were described.



53

Establishment of a Culture System for and Lifecycle Dynamics of the Tardigrade Hypsibius dujardini.

Fran THOMAS, Jennifer DAUB, Habib MAROON, Aziz ABOOBAKER, and Mark BLAXTER

Institute of Cell, Animal and Population Biology, Ashworth Laboratories, University of Edinburgh, Kings Buildings, Edinburgh, EH9 3JT, UK. Abstract. We have initiated a programme of evolutionary developmental biology research on a

cultured tardigrade, Hypsibius dujardini. Tardigrades are an attractive organism for comparative

work because of their basal position in the pan-Arthropoda, and the observation that they share

some morphological and developmental characteristics with other Ecdysozoa such as the

nematodes. Previously, developmental and other research on tardigrades has been hampered by

an inability to grow them in culture. We have established conditions for culture of a small, fresh

water, herbivorous tardigrade using a defined, clonal food source (Chlamydomonas reinhardtii)

and are able to rear tens of thousands of tardigrades. Importantly, we are also able to rear single

tardigrades in multiwell plates. The culture system is based on seeding large volumes of fresh

water with ample C. reinhardtii grown in Bold's medium. Aeration and illumination at 20 degC

is sufficient to maintain cultures for several weeks. H. dujardini appears to be matriclonal, as we

are able to rear isolated eggs or juveniles in isolation to fecund adulthood. Development time in

the egg is about 4 days at 20 degC, and the juvenile undergoes several larval moults before first

laying eggs at 6 days old. The animals continue to moult as adults, and lay additional clutches of

eggs every 2 to 4 days thereafter, for at least 4 weeks. The eggs are laid within the shed cuticle,

allowing us to easily follow a clutch of siblings that were laid and initiated development near-

synchronously. In our culture system, mature adults can lay 15 or more at each moult. This is

probably due to optimal nutritional conditions. We are investigating the developmental timings

of eggs from different-sized clutches, and the ability of this species to undergo cryptobiosis

(either desiccation or freezing).



54

Tardigrades of The Faroe Islands

Birna V. TRYGVADÓTTIR Zoological Museum, Invertebrate Department, Universitetsparken 15, DK-2100 Copenhagen Ø, Denmark, e-mail: [email protected] Abstract. The tardigrade fauna of the Faroe Islands has never been subject to thorough

investigations, and there are only a few records available from the literature. Tuxen made a

synopsis of the tardigrade fauna in 1941 based on scarce material, and his species list include 18

species. This paper presents some preliminary results from an ongoing investigation of the

freshwater and terrestrial tardigrade fauna of the Faroe Islands. Samples were collected in 2001-

2003 at several locations, habitats and altitudes on the Isles. So far the species list of hetero- and

eutardigrades contains 28 species, including a new genus of Eohypsibiidae from high mountain

moss-cushions. The collections also include the first record of the genus Amphibolus from the

Faroe Islands.



55

Tardigrades Density and Diversity in four life zones of Costa Rica.

Jonnathan HERRERA-VÁSQUEZ

Museo de Zoología, Universidad de Costa Rica. E-mail: [email protected]

Abstract: The objective of this study is determine the diversity, average density and

association between species of tardigrades of folious lichens in four life zones of Costa Rica:

Tropical moist forest (T - mf), Premontane moist forest (P - mf), Lower montane moist forest

(LM - mf) and Montane wet forest (M -wf). A total of 77 samples of folious lichens were

analyzed during 2002. 14 species of tardigrades were found with 118.2 ind/ cm2 average

density. The most diverse zone was the premontane moist forest (H = 2.057) and lowest low

montane moist forest (H = 0.90). were observed that in three life zones the Heterotardigrada

Class is the most abundant (t = 1.9432, gl = 6, p = 0.05333). Only between Milnesium

tardigradum species and Echiniscus sp2 were found significative association (p = 0.039).



56

Tardigrades (Phylum Tardigrada) from the western part of the Central

Valley, Costa Rica with Some Ecological Annotations. Jonnathan HERRERA -VASQUEZ1 & Mario Vargas VARGAS2.

1. Museo de Zoología, Universidad de Costa Rica. E - mail: [email protected]

2. Facultad de Microbiología, Universidad de Costa Rica. Address: Laboratorio de Artropodología Médica (270 B), Facultad de Microbiología, Universidad de Costa Rica.

Abstract: During 2001 and 2002, tardigrades of Folious lichens from the western part of

the Central Valley of Costa Rica were collected at different altitudinal regions and fixed for

their identification. There were found four genera and seven species: Macrobiotus richtersi,

Macrobiotus harmsworthi, Macrobiotus areolatus, Isohypsibius bakonyensis Milnesium

tardigradum, Echiniscus bigranulatus and Echiniscus angolensis. The most frequent species

was M, ricthersi (31 %) and the least M. areolatus with (7.33 %) in the samples analyzed. This

is the first record of Echiniscus angolensis for Central America. There are now known 13

species of tardigrades for Costa Rica and 7 for the area of study.



57

A Family Analysis of Tardigrade Phylogeny

P. Brent NICHOLS1, Diane R. NELSON2, James R. GAREY1 1Department of Biology, University of South Florida, Tampa, FL U.S.A. 2Department of Biological Sciences, East Tennessee State University, Johnson City, Tennessee, U.S.A. Abstract. There is no overall phylogenetic hypothesis of tardigrade evolution in the current

literature. The present study developed a morphological data set suitable for cladistic analysis at

the family level. A data matrix consisting of 50 characters for 15 families of Tardigrada was

analyzed by maximum parsimony. Kinorhynchs, loriciferans, and gastrotrichs were used as

outgroups, and ground pattern characters for tardigrades were established from the literature.

The results agree with the currently accepted hypothesis that Eutardigrada and Heterotardigrada

are each monophyletic groups. Among the eutardigrades, Eohypsibiidae was found to be a sister

group to Macrobiotidae + Hypsibiidae. Necopinatidae appears to be basal among the Parachaela

while Milnesiidae was the basal eutardigrade. The enigmatic Apodibius was also found to be

basal among the eutardigrades but this position is inconclusive because of its lack of characters.

Among the heterotardigrades the family Oreellidae was found to be basal. Coronarctidae +

Batillipedidae were found be sister groups to Echiniscoidea + Echiniscidae. Therefore, the order

Arthrotardigrada appears to be paraphyletic and the order Echiniscoidea may be polyphyletic.

The 18S rRNA gene sequence of Batillipes was obtained and its addition to a previously

published dataset supports the monophyly of Heterotardigrada. The analysis of the

morphological data set suggests that 18S rRNA sequences from members of Oreellidae,

Renaudarctidae, and Halechiniscidae would be useful to test the paraphyletic and polyphyletic

groups that appeared in the morphological analysis.



58

Symposium Participants

Diane Nelson East Tennessee State University Box 70703 ETSU Johnson City TN 37614-1710 USA 423-439-4376 [email protected]

Lois Bateman Sir Wilfred Grenfell College University Drive Corner Brook Newfoundland and Labrador A2H 6P9 Canada 709-637-6247 [email protected]

James Garey University of South Florida Department of Biology 4202 E. Fowler Ave. SCA110 Tampa FL 33620 USA 813-974-3900 [email protected]

Mark Blaxter ICAPB Ashworth Labs, King's Buildings Edinburgh EH9 3JT UK +44 131 650 6760 [email protected]

Frank Romano Jacksonville State University 700 Pelham Road N. Biology Department Jacksonville AL 36265 USA 256-782-5038 [email protected]

Harry Meyer McNeese State University PO 92000, Dept of Biol. Environ. Sciences McNeese State University Lake Charles Louisiana 70609 USA 337-475-5671 [email protected]

Juliana Hinton McNeese State University P.O. Box 92000 Lake Charles LA 70609-2000 USA (337)475-5651 [email protected]

Amber Hohl Iowa State University 2604 Stange Rd. Apt. 7 Ames IA 50010 U.S.A. 319-470-1439 [email protected]



59

Habib Maroon University of Edinburgh Institute of Cell, Animal and Poulation Biology, King's Buildings West Mains Road. Edinburgh Scotland EH9 3JT UK 44 (0) 131 650 6761 [email protected]

James Young Jacksonville State University 700 Pelham Road N. Biology Department Jacksonville AL 36265 USA 256-782-5642 [email protected]

Jennifer Daub University of Edinburgh Ashworth laboratories West Mains Road Edinburgh EH9 3JT UK +44 131 650 6761 [email protected]

Lukasz Michalczyk Jagiellonian University, Department of Zoopsychology ul. Ingardena 6 Krakow 30-060 POLAND +48126336377 ext.2461 [email protected]

Robert DaFoe Jacksonville State University 700 Pelham Road N. Biology Department Jacksonville AL 36265 USA 256-782-5642 [email protected]

P. Brent Nichols Univ. of South Florida Dept. of Biology, SCA 110 4202 E Fowler Ave Tampa FL 33620 USA 813-974-8967 [email protected]

Jonnathan Herrera-vásquez Universidad de Costa Rica El Tajo casa Nº 2 Esparza Puntarenas Costa Rica 207 4193 [email protected]

Colleen Mitchell Jacksonville State University 700 Pelham Road N Biology Dept. Jacksonville AL 36265-1602 USA 256-782-5642 [email protected]



60

Jesper Guldberg Hansen Zoological Museum, University of Copenhagen Universitets parken 15 DK-2100 Copenhagen East DK-2100 Denmark 35 32 11 16 [email protected]

Nigel Marley School of Biological Sciences, University of Plymouth Drake Circus Plymouth Devon PL4 8AA United Kingdom 44-(0)1752-232939 [email protected]

Alexandra Avdonina Vladimir State Pedagogical University Stroiteley prospect, 11 Vladimir 600024 Russia 10-7-0922-339784 [email protected]

Frances Thomas ICAPB, University of Edinburgh. Ashworth Labs, King's Buildings, West Mains Road, Edinburgh Scotland EH9 3JT United Kingdom (0131) 650 6761 [email protected]

Clark Beasley McMurry University Department of Biology Abilene Texas 79697 U.S.A. 325-793-3867 [email protected]

Peter Degma Comenius University, Faculty of Natural Sciences Mlynska dolina B-1 Bratislava SK-842 15 Slovak Republic +421 2 60296492 [email protected]

Hiroki Harada National Agricultural Research Center for Tohoku Region Arai Fukushima-city Fukushima Prefecture 960-2156 Japan +81-024-593-6175 [email protected]

Iben Heiner Zoological Museum of Copenhagen Universitetsparken 15 Copenhagen OE 2100 Denmark +45 35321039 [email protected]



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Birna Trygvadóttir Zoological Museum of Copenhagen Universitetsparken 15 Copenhagen OE 2100 Denmark +45 35321039 [email protected]

Reinhardt Kristensen Zoological Museum of Copenhagen Universitetsparken 15 Copenhagen OE 2100 Denmark +45 35321118 [email protected]

William Miller Chestnut Hill College 9601 Germantown Ave Philadelphia PA 19118 USA 215-248-7029 [email protected]

Ruth Dewel Appalachian State University Boone NC 28608 USA 828 262 2682 [email protected]

Jerome Regier Center for Biosystems Research, University of Maryland Biotechnology Institute Plant Sciences Building, Rm 5140 College Park MD 20742 USA 301 405 7679 [email protected]

Roberto Guidetti University of Modena and Reggio Emilia Via Campi 213/d Modena Modena Italy 41100 Italy ++39 0592055555 [email protected]

Lorena Rebecchi University of Modena and Reggio Emilia - Department of Animal Biology Via Campi 213/D Modena 41100 Italy +39 0592055553 [email protected]

Roberto Bertolani University of Modena and reggio Emilia - Department of Animal Biology Via Campi 213/D Modena 41100 Italy +39 0592055545 [email protected]



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Mary Marshall 10277 S. St. Rd. 335 Pekin Indiana 47165 United States of America (812)-366-3553 [email protected]

Atsushi Suzuki Keio University Hiyoshi 4-1-1 Kohoku-ku Yokohama Kanagawa 223-8521 Japan 81-45-566-1329 [email protected]

Wataru Abe Division of Biological Sciences, Graduate School of Science, Hokkaido University Kita-10, Nishi-8 Kita-ku Sapporo Hokkaido 060-0810 Japan +81-11-706-3524 [email protected]

Daiki Horikawa Department of Environmental Earth Science, Hokkaido University Kita 10, Nishi 5, Kita-ku Sapporo Hokkaido 060-0810 Japan +81-11-706-2251 [email protected]

Michael Collins Memorial University of Newfoundland Elizabeth Avenue Arts-Administration Building St. John's Newfoundland and Labrador A1C 5S6 Canada 709-737-8411 [email protected]

Richard Helm Virginia Tech West Campus Drive Blacksburg VA 24061 USA 540-213-4088 [email protected]

María Fernández Facultad de Cs. Exactas y Naturales- UNLPam Uruguay 151 Santa Rosa La Pampa 6300 Argentina 54 - 2954 - 42 5166 [email protected]

Alejandra Rocha Facultad de Cs. Exactas y Naturales - UNLPam Uruguay 151 Santa Rosa La Pampa 6300 Argentina 54 2954 42 5166 [email protected]



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Karsten Klage Virginia Tech Biochemistry 205 Engel Hall Blacksburg VA 24061 USA 540-231-8435 [email protected]

Jette Eibye-Jacobsen Zoological Museum, Copenhagen Universitetsparken 15 2100 Copenhagen Ø Copenhagen Denmark Denmark +45 35321081 [email protected]

Tiziana Altiero University of Modena and Reggio Emilia Via Campi, 213/D Modena I-41100 Italy +390592055554 [email protected]

Matthew Boeckner Memorial University of Newfoundland Department of Biology St. John's Newfoundland A1B3X9 Canada (709)737-8411 [email protected]

Maggie Ray North Carolina State University 4277 The Oaks Drive Raleigh NC 27606 USA 919-233-8750 [email protected]

Clayton Marshall Eastern High School 10277 S. St. Rd. 335 Pekin IN 47165 United States of America (812)366-3553 [email protected]

Gallo D'Addabbo Maria Dipartimento Zoologia Università Bari Via Orabona ,4 Bari Italy Bari 70126 ITaly +39 0805443345 [email protected]

Paul Bartels Warren Wilson College WWC 6032 PO Box 9000 Asheville NC 28815 USA 828-771-3781 [email protected]



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Eliana Narvaez-Parra University of Puerto Rico Calle Mendez Vigo 165-0 apt 1007 Mayaguez Puerto Rico 00681-3256 Puerto Rico 787-8324040 ext 2269 [email protected]

Javier Jerez-Jaimes University of Puerto Rico Calle Mendez Vigo 165-0 apt 1007 Mayaguez Puerto Rico 00681-3256 Puerto Rico 787-832-4040 ext 2269 [email protected]



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Documents

9th International Symposium on Tardigrada St. Pete Beach ... · Tardigrade Research: Where Have We Been? Where Are We Going? 10:30am Morning Break Mediterranean Palm Session 2 Phylogeny