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Australian Journal of Entomology
(2002)
41
, 221–225
Three new species of
Orphninotrichia
Mosely (Trichoptera: Hydroptilidae) from Barrington Tops, New South Wales, a distribution extended, and remarks on generic placement
Alice Wells
Australian Biological Resources Study, Environment Australia, GPO Box 787, Canberra, ACT 2601, Australia.
Abstract
Three new species are described in the endemic Australian microcaddisfly genus
Orphninotrichia
Mosely (Trichoptera: Hydroptilidae: Hydroptilinae), all collected in the Barrington Tops area of north-eastern New South Wales:
Orphninotrichia bilobata
sp. n.,
O. claviculata
sp. n. and
O. dundungra
sp. n. From the same area,
Orphninotrichia papillata
Wells, described from central Victoria, is newlyrecorded and noted for the atypical presence of a large gland on the dorsum of the male head.Comments are made on the still unresolved affinities of the genus
Orphninotrichia
, and a key to malesof all species is provided.
Key words
Barrington Tops, Hydroptilidae, key,
Orphninotrichia
, Trichoptera.
INTRODUCTION
The Australian microcaddisfly genus
Orphninotrichia
Mosely is an oddity in the Hydroptilidae (Trichoptera) for itsuncharacteristic habits and morphology. It is recorded fromTasmania and eastern mainland Australia from FleurieuPeninsula, South Australia, to north-eastern Queensland, thefar north of the Northern Territory and from Lord HoweIsland. Seventeen species are now known for the genus(Wells 1980, 1983, 1990a, 1999), including three that arenewly described here, and adult males of all species can beidentified using the revised key provided.
Orphninotrichia
is placed currently in the Hydroptilini,but the species have several features more characteristic ofmembers of the Stactobiini, which is known in Australiafrom a single species in north-eastern Queensland. Amongthese features are (generally) narrow distributions, the adultshaving been collected from one or few waterfalls or cascadeswhere the larvae graze on epilithos in soak or splash zones,or beneath the torrent on the face of the falls (Wells 1999). Inaddition, adults appear to be active diurnally, with malesoften seen gathering at specific sites on riparian vegetationnear falls or riffles, and showing lekking behaviour.
Not all species have restricted distributions, however, and
O. maculata
Mosely has been collected from Tasmania, andwidely in south-eastern mainland Australia to as far north assouth-eastern Queensland, and here a highly disjunct distri-bution is reported for
O. papillata
Wells. Described fromcentral Victoria (Wells 1980),
O. papillata
is here reportedfrom the Barrington Tops area of New South Wales, where itwas collected together with three other species that are newlydescribed here.
The four species of
Orphninotrichia
from Lord HoweIsland are unusual in that in several species adult males and/or larvae diverge from the very constant morphologyobserved in all known mainland species (Wells 1999). How-ever, a previously unnoticed feature of male
O. papillata
ishere described and illustrated: a large dorsal scent gland onthe head. The function of such a structure is a matter forconjecture. Perhaps these glands are involved in male–malebehaviour, as males predominated in the sweep-net sampletaken by day from vegetation beside a waterfall in theBarrington Tops area. Another atypical feature in two ofthe new species is the absence of sensilla placodea on theantennal segments of
O. curvata
sp. n. and
O. claviculata
sp. n., apparently replaced by large numbers of sensillaauricillica, a condition similar to that seen in Australian
Oxyethira
species (Wells 1984).The phylogenetic position of
Orphninotrichia
isunresolved (Wells 1987). The genus conforms with membersof the Hydroptilinae, tribe Hydroptilini, but has a curiouscombination of character states. Similar to members of thegenus
Hydroptila
Dalman, adults have a tibial spur formulaof 0,2,4, but, unlike
Hydroptila
, have ocelli. Dorsal headglands similar to that of the male of
O. papillata
occur inmales of many Oriental and Nearctic
Hydroptila
species, butcuriously, not in any Australian
Hydroptila
species. Femalegenitalia of
Orphninotrichia
also show some resemblance tothose of
Hydroptila
, there usually being a pronounced glandventrally on abdominal segment VIII. Unlike
Hydroptila
,however, the form of the aedeagus is invariant, and closelyresembles that of species of
Tricholeiochiton
Kloet andHincks.
Not emphasised hitherto, but generally illustrated infigures of male genitalia of
Orphninotrichia
, is the variableform of the basal apodeme of the inferior appendages. This isa deep V-shape in
O. regia
Wells,
O. justini
Wells and
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222
A Wells
O. plumosa
Wells; a deep U-shape in
O. gilva
Wells; a stouttongue-like structure in
O. maculata
Mosely and
O. papillata
;and a median peg, short in
O. media
Wells, and elongate–slender in
O. silicis
Wells,
O. bilobata
sp. n.,
O. claviculata
sp. n. and
O. dundungra
sp. n. A similar peg-shaped anteriorventral apodeme in the male genitalia is characteristic of
Orthotrichia
spp., but I have not noticed it in other genera. Itsoccurrence in some
Orphninotrichia
species may simply beconvergent.
In larvae of
Orphninotrichia
(Wells 1985), all limbs aresubequal and anal claws lack accessory hooks, usually con-sidered plesiomorphic features. However, abdominal tergite Iis sclerotised, which is a derived feature also seen in theAustralian genus
Hellyethira
Neboiss, and cases are con-structed mainly of silk, often with more or less sand incorpo-rated and usually built in a manner that must be considered tobe autapomorphic in the Hydroptilinae. The
Oxyethira
-typeflask-shaped case seen in the Lord Howe Island
Orphnino-trichia squamosa
(Wells 1999) only adds further to theconundrum, which seems to be becoming more complex asfurther
Orphninotrichia
species are discovered. All larvalcases collected in the Barrington Tops area are the usualsymmetrical purse-shaped structures, with a slight medianconstriction (see Wells 1985), built of silk secretion withsome sand, and the larvae show no unusual features. It wasnot possible to identify the larvae to species.
Of the species newly described here, in male genitalicfeatures,
O. curvata
sp. n. most closely resembles
O. justini
Wells from south-eastern Victoria, while the other twospecies show similarities with each other in many respects,but are dissimilar from other congeners.
MATERIALS AND METHODS
The material studied here was almost all collected by sweep-ing of riparian vegetation, and was prepared for study follow-ing the methods of Wells (1990b). I collected all specimensand they are lodged in the Australian National Insect Collec-tion (ANIC).
SYSTEMATICS
Orphninotrichia bilobata
sp. n. (Figs 1,2)
Types.
New South Wales
.
Holotype, male (on slide), Chi-chester State Forest, Dundungra Falls, 24.xii.2000. Paratype:1 male (on slide), collected with holotype.
Diagnosis.
Characterised by the bilobed postero-mesial pro-jections on sternite VIII, and distinguished from several otherspecies with similar but shorter postero-mesial projections bya pair of sclerotised processes between the bases of the lobes.
Description.
Adults small, uniformly black.
Male.
Wingsslender, acuminate apically, without scales or scent brushes.Anterior wing length, 1.7–2.0 mm. Antennae 23-segmented,flagellar segments with scattered sensilla placodea. Genitaliaas in Figs 1,2. Abdominal VIII with length almost two times
width, subrectangular in ventral view, posteriorly producedinto a pair of conical lobes, with a pair of small blackprocesses ventrally between their bases. Sternite IX retractedwithin VIII. Tergite X a stout membranous structure. Inferiorappendages elongate, forming apically setate lobes, anteriorbasal apodeme deeply V-shaped. Subgenital plate divideddistally, forming a lateral sclerotised lobe and more disto-mesial stoutly digitate processes with a seta apically. Aede-agus elongate, more than two times length of sternite VIII.
Etymology.
Named for the paired peg-like apico-ventrallobes on sternite VIII.
Distribution.
Known only from the type locality.
Orphninotrichia dundungra
sp. n. (Figs 3,4)
Types.
New South Wales
.
Holotype, male (on slide), Chi-chester State Forest, Dundungra Falls, 24.xii.2000; paratypes:10 males (one on slide), 1 female, collected with holotype;1 male (on slide), same locality, 25.xii.2000; 1 male, Chi-chester State Forest, Jerusalem Creek, 25.xii.2000.
Diagnosis.
Although males of this species resemble those of
O. subulata
Wells in having sternite VIII greatly producedposteriorly to form a triangular shield under the genitalia,they more closely resemble
O. justini
in the strongly curvedaedeagus, and more elongate ventral genitalic structures.
Description.
Adults small, uniformly black.
Male.
Wingsslender, acuminate apically, without scales or scent brushes.Anterior wing length, 1.3–1.8 mm. Antennae 21-segmented,flagellar with a very few sensilla placodea on only distalsegments. Genitalia as in Figs 3,4. Abdominal sternite VIIwith a postero-mesial spine. Sternite VIII stoutly subtriangularposteriorly with margins stepped, forming a plate beneathgenitalia; sternite IX retracted within VIII. Tergite X in formof two elongate triangular membranous structures. Inferiorappendages elongate peg-like, broadest basally, apices rounded,sclerotised and rugose; with a slender peg-like basal apo-deme. Subgenital plate undivided, apically resembling infe-rior appendages. Aedeagus, about 2 times length of sterniteVIII, strongly curved downwards in lateral view.
Etymology.
Named for the type locality.
Distribution.
Known only from two streams in theBarrington Tops area.
Orphninotrichia claviculata
sp. n. (Figs 5,6)
Type.
New South Wales.
Holotype male (on slide), ChichesterState Forest, Dundungra Falls, 24.xii.2000.
Diagnosis.
Characterised by males with a bilobed postero-mesial projection on sternite VIII, lobes apically acute, bywhich it is clearly distinguished from the otherwise similarcentral-Victorian
O. regia
.
Description.
Adults medium-sized, uniformly black.
Male.
Wings slender, acuminate apically, without scales or scentbrushes. Anterior wing length, 2.3 mm. Antennae damaged,more than 22-segmented, without sensilla placodea. Genita-lia as in Figs 5,6. Abdominal VIII basically quadrate in
Three new species of
Orphninotrichia
223
Figs 1–8.
Orphninotrichia
spp.
(1–6,8)
Male genitalia.
(1,2)
O. bilobata
sp. n., ventral and lateral view.
(3,4)
O. dundungra
sp. n., ventral and lateral view.
(5,6)
O. claviculata
sp. n., ventral and lateral view.
(8)
O. papillata
Wells, lateralview.
(7)
O. papillata
Wells, head dorsal view, showing scent gland. adr, androconia; ae, aedeagus; sc gld, scent gland; sp. st VII,spine on abdominal sternite VII; st VIII, abdominal sternite VIII. Scale bar = 0.1 mm for Fig. 7.
224
A Wells
ventral view but postero-mesially produced into a pair ofapically acute lobes separated by a U-shaped cleft. SterniteIX almost width of VIII, with stout lateral lobes as long asgenitalic structures. Tergite X a stout membranous plate.Inferior appendages stoutly downturned distally, sclerotisedapically setate, anterior basal apodeme a slender mesial peg-like process. Subgenital plate divided distally, forming alateral lobe that is sclerotised apically and has a long setasubapically and a more mesial lobe, downturned distally andsclerotised apically. Aedeagus elongate, more than threetimes length of sternite VIII.
Etymology.
From Latin,
claviculatus
, being descriptive ofthe shape of postero-mesial projection on sternite VIII.
Distribution.
Known only from the type locality, DundungraFalls, Chichester State Forest, New South Wales.
Orphninotrichia papillata
Wells (Figs 7,8)
Orphninotrichia papillata
Wells 1980: 635.
Type.
Victoria
.
Holotype male, Tawonga (Museum Victoria)(examined).
Other material examined.
New South Wales.
4 males (2 onslides), 1 female (on slide), Chichester State Forest, ProblemCreek, 23.xii.2000; 6 males (2 on slides), 4 females (onslide), Chichester State Forest, Jerusalem Creek, 25.xii.2000.
Diagnosis.
Distinguished from
O. silicis
Wells, the onlyother congener known to have androconia apically on sterniteVIII, by having a row around the concavity on the apicalmargin, rather than a single mesial cluster.
Description.
Anterior wing length: males, 1.6–1.9 mm,females, 1.8–2.1 mm.
Distribution.
Known from central Victoria and now fromseveral sites in the Barrington Tops Range of north-easternNew South Wales.
Remarks.
New figures are given here to illustrate the scentgland (Fig. 7), noticed first in the New South Wales speci-mens, and subsequently confirmed as present in the typespecimens, and also to correct a mistake in the originalfigures and description. As illustrated in Fig. 8,
O. papillata
has a group of four androconia apically on the lateral lobes ofabdominal segment IX, not a sclerotised spur as indicated inthe original description.
Key to males of
Orphninotrichia
1 Forewings modified, having patches of black scales(androconia) or golden scales................................... 2
– Forewings unmodified, in life, black with smallwhite patch on posterior margin, in preservedspecimens appearing uniformly dark ....................... 3
2 Forewings with patches of black scales on proximalthird; Lord Howe Island (Wells 1999: Fig. 2)................................................................................
O. squamosa
– Forewings covered almost entirely with goldenscales; Lord Howe Island (Wells 1999: Fig. 3) ..................................................................................
O. gilva
3 Abdominal sternite ‘V’ with tuft of dark fimbriatehairs at opening of gland; lateral lobes of abdominaltergite IX in dorsal view, divided distally to formtwo unequal-sized lobes; Lord Howe Island (Wells1999: Figs 6,8)..........................................
O. plumosa–
Not as above ............................................................. 4
4 Abdominal sternite VIII, subtriangular in ventralview, being produced distally to rounded apex........ 5
– Abdominal sternite VIII, subrectangular to subquad-rate, may be shallowly excavated mesially, or producedto form pair of short apico-mesial lobes................... 7
5 Distal margin of sternite VIII stepped subapically(Fig. 3)..................................................
O. dundungra– Distal margin of sternite VIII smoothly tapered to
apex, not stepped subapically................................... 6
6 Lateral lobes of abdominal segment IX with innerapical sclerotised spur (Wells 1980: Fig. 16).....................................................................................O. media
– Lateral lobes of abdominal segment IX without innerapical sclerotised spur (Wells 1983: Fig. 42).................................................................................O. subulata
7 Small black androconia on apical margin ofabdominal sternite VIII ............................................ 8
– Without androconia on apical margin of abdominalsternite VIII .............................................................. 9
8 Androconia bordering shallow excavation on apicalmargin of abdominal sternite VIII (Wells 1980:Fig. 18); large dorsal scent gland on head (Fig. 7)....................................................................... O. papillata
– Androconia clustered mesially on apical margin ofabdominal sternite VIII (Wells 1980: Fig. 22);without a dorsal scent gland on head ........... O. silicis
9 Apico-mesial margin of abdominal sternite VIIIproduced slightly, but without mesial lobes........... 10
– Apical margin of abdominal sternite VIII producedto form pair of short mesial lobes........................... 11
10 Small knob on apico-mesial margin of abdominalsternite VIII sclerotised apically (Wells 1999:Fig. 10); Lord Howe Island ........................ O. rugosa
– Apico-mesial margin of abdominal sternite VIIIsmoothly rounded, membranous (Wells 1980:Fig. 10); Tasmania...........................................O. acta
11 Apico-mesial lobes on abdominal sternite VIIImembranous apically.............................................. 12
– Apico-mesial lobes on abdominal sternite VIIIdarkly sclerotised apically...................................... 14
12 Apico-mesial lobes on abdominal sternite VIIIapically acute, apices divergent (Wells 1983:Fig. 37) .........................................................O. justini
– Apico-mesial lobes on abdominal sternite VIIIapically rounded ..................................................... 13
13 Inferior appendages curved mesially, roundedapically (Wells 1983: Fig. 39)............ O. benambrica
– Inferior appendages not curved mesially, truncateapically (Wells 1980: Fig. 6)...................O. maculata
Three new species of Orphninotrichia 225
14 Apico-mesial lobes on abdominal segment VIIIdigitiform, a pair of smaller sclerotised processes atbase (Fig. 1).............................................. O. bilobata
– Apico-mesial lobes on abdominal segment VIII notdigitiform, without second pair of processes.......... 15
15 Lateral lobes of segment IX ventrally fused tosternite VIII resulting in a deep mesial concavity,small triangular sclerotised lobes apico-mesially;northern Northern Territory (Wells 1990a: Fig. 8) ........................................................................O. originis
– Not as above ........................................................... 1616 Apico-mesial lobes on abdominal segment VIII
acute apically (Fig. 5) ...........................O. claviculata– Apico-mesial lobes on abdominal segment VIII
rounded apically (Wells 1980: Fig. 13).........O. regia
REFERENCES
Wells A. 1980. A review of the Australian genera OrphninotrichiaMosely and Maydenoptila Neboiss (Trichoptera: Hydroptilidae)
with descriptions of new species. Australian Journal of Zoology 28,627–645.
Wells A. 1983. New species in the Australian Hydroptilidae (Trichop-tera), with observations on relationships and distributions.Australian Journal of Zoology 31, 629–649.
Wells A. 1984. Comparative studies on antennal features of adultHydroptilidae (Trichoptera). In: Proceedings of the IVth Interna-tional Symposium on Trichoptera (ed. JE Morse) pp. 423–440.Junk, The Hague, Netherlands.
Wells A. 1985. Larvae and pupae of Australian Hydroptilidae (Trichop-tera), with observations on general biology and relationships.Australian Journal of Zoology, Supplementary Series 113, 1–69.
Wells A. 1987. On the biogeography of the Oxyethira group, tribe Hydrop-tilini (Hydroptilinae: Hydroptilidae: Trichoptera). In: Proceedings ofthe Vth International Symposium on Trichoptera (eds M Bournaud &H Tachet) pp. 133–138. Junk, Dordrecht, Netherlands.
Wells A. 1990a. New species and a new genus of microcaddisfly fromnorthern Australia, including the first Australian record of the tribeStactobiini (Trichoptera: Hydroptilidae). Transactions of the RoyalSociety of South Australia 114, 107–128.
Wells A. 1990b. The microcaddisflies (Trichoptera: Hydroptilidae) ofNorth Sulawesi. Invertebrate Taxonomy 3, 363–406.
Wells A. 1999. The micro-caddisflies of Lord Howe Island (Hydrop-tilidae: Trichoptera: Insecta). Aquatic Insects 21, 221–230.
Accepted for publication 3 February 2002.
