Microhabitats Occupied by Loxosceles intermedia and Loxosceles laeta (Araneae: Sicariidae) in Curitiba, Paraná, Brazil

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Microhabitats Occupied by Loxosceles intermedia andLoxosceles laeta (Araneae Sicariidae) in Curitiba ParanaacuteBrazilAuthor(s) Marta Luciane Fischer and Joatildeo Vasconcellos-NetoSource Journal of Medical Entomology 42(5)756-765 2005Published By Entomological Society of AmericaDOI httpdxdoiorg1016030022-2585(2005)042[0756MOBLIA]20CO2URL httpwwwbiooneorgdoifull1016030022-2585282005290425B07563AMOBLIA5D20CO3B2

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POPULATION AND COMMUNITY ECOLOGY

Microhabitats Occupied by Loxosceles intermedia and Loxosceles laeta(Araneae Sicariidae) in Curitiba Parana Brazil

MARTA LUCIANE FISCHER1 AND JOAO VASCONCELLOS-NETO2

J Med Entomol 42(5) 756ETH765 (2005)

ABSTRACT A survey was done of the environments and substrata occupied byLoxosceles intermediaMello-Leitao 1934 and Loxosceles laeta (Nicolet 1849) (Araneae Sicariidae) in urban woods andanthropic constructions in Curitiba In total 2099 trees 364 decaying logs as well as stones and rootsbuilt-up areas and wasteland in six urban parks and 60 residences were inspected In total 1775 m2

of vegetation was inspected but spiders and their vestiges were collected only in and around buildingsin urban parks and residencesL intermediawas more common thanL laetaand occurred both indoorsand outdoors whereas L laetawas more common indoors in wooden houses The two species did notoccur in the same microhabitats although both preferred paper wood and construction materialsSpiders collected in urban parks were heavier than those collected in residences although only malescollected in urban parks were larger than those from residences The lack of vestiges indicative of aprevious occupation in the urban parks suggested that both species occupied primarily the anthropicenvironment where they found numerous substrata that offered thermal isolation and suitableconditions for web THORNxation ecdysis and reproduction

KEY WORDS anthropic environment habitat selection loxoscelism

THE GENUS Loxosceles (Araneae Sicariidae) is cosmo-politan and synanthropic with two species Loxosceleslaeta(Nicolet 1849) andLoxosceles rufescens(Dufour1820) having a worldwide distribution In Brazil thegenus is represented by nine speciesLoxosceles similisMoenkhaus 1898Loxosceles amazonicaGertsch 1967Loxosceles adelaida Gertsch 1967 Loxosceles puortoiMartins Knysak amp Bertani (2002) Loxosceles anoma-laAlvares Rodrigues amp De Maria 2004 LoxoscelesgauchoGertsch 1967 Loxosceles hirsutaMello-Leitao1931 L laeta and Loxosceles intermediaMello-Leitao1934 (Gertsch 1967) with the latter four species oc-curring in the Brazilian state of Parana L laeta and Lintermedia account for 10 and 90 respectively of theLoxosceles spiders found in Curitiba the capital ofParana (Fischer 1994) L laeta is native to westernSouth America probably Argentina or Chile and hasbeen transported for several countries (eg theUnited States Finland and Australia) whereas L in-termedia is found only in Argentina and southern andsoutheastern Brazil (Gertsch 1967)

OutdoorsLoxosceles spiders occur in many habitatsincluding rock cavities beneath rocks and beneathloose bark in hollow trees and abandoned termitenests in crevices of decaying logs under leaf litter incaves and grottos in rock crevices along the shorelineand under shaded gravel in dry areas (Bucherl 1962

Delgado 1966 Hite et al 1966 Galiano 1967 Gertsch1967 Russell et al 1969 Schenone and Lentoja 1975Newlands et al 1982 Borkan et al 1995 Rinaldi et al1998) Hite et al (1966) described the bluffs of north-western Arkansas as one of the probable primary hab-itats of L reclusa because they provided excellentenvironmental conditions at high and low tempera-tures

Indoors Loxosceles spiders occur preferentially indark dry undisturbed places such as wooden or card-board boxes broken and irregular szligoors behind pic-tures or objects beneath or behind furniture drawersclothing and stored paper and in corners (Bucherl1961 1962 Levi and Spielman 1964 Hite et al 1966Galiano 1967 Gertsch 1967 Gorham 1968 Schenoneet al 1970 Huhta 1972 Whitcomb and Wallace 1972Schenone and Lentoja 1975 Rinaldi et al 1998) Thesespiders also are found in old tires and dumps (Hite etal 1966) and in piles of construction material aroundbuildings (Bucherl 1961 1962 Gertsch 1967 Canese1972 Rinaldi et al 1998) Borkan et al (1995) reportedan infestation of L rufescens in orchard litter andcardboard boxes placed around the bases of trees tosoften the fall of ripe fruit

Few studies have evaluated the factors that favorthe occupation of buildings even for medically im-portant species of Loxosceles Schenone et al (1970)assessed the prevalence of L laeta in residences inChile whereas others (Hite et al 1966 Delgado 1966Vetter and Barger 2002) reported the preferentialoccurrence in a speciTHORNc room or construction withoutspecifying the substratum present The habits of Lox-

1 Nucleo de Estudos do Comportamento Animal Departamento deBiologia CCBS Pontifotildecia Universidade Catolica do Parana CuritibaPR Brazil

2 Departamento de Zoologia Instituto de Biologia UniversidadeEstadual de Campinas Campinas SP Brazil

0022-2585050756ETH0765$04000 2005 Entomological Society of America

osceles and the substrata occupied by these spidersusually favor passive dispersion by humans and has ledto some species being transported around the worldto occupy new habitats (Levi and Spielman 1964 Wal-dron and Russell 1967 Gorham 1968 Madon and Hall1970 Huhta 1972 Unzicker 1972 Whitcomb and Wal-lace 1972 Southcott 1976 McDaniel and Jennings1983 Borkan et al 1995) although Vetter and Bush(2002) show that at least in North AmericaLoxoscelesspiders rarely colonize outside of native areas Ac-cording to McDaniel and Jennings (1983) a singlefemale introduced into a house can potentially estab-lish populations in an urban area and in the wildaround buildings Success in the occupation of newenvironments is favored by the mechanism of dis-persal great longevity and tolerance to starvation andthe lack of water (EskaTHORN et al 1977 Lowrie 1980 1987Greenstone and Bennett 1980) Colonization indoorsis favored by heaters and air conditioners that mini-mize extreme temperatures (Delgado 1966 Schenoneand Lentoja 1975) and by the availability of differentsubstrata abundant prey and the absence of potentialpredators (Fischer and Vasconcellos-Neto 2005b)

In Curitiba (latitude 25 25 48 S and longitude 4916 15 W) city in the southern part of Brazil andcapital state of Parana Loxosceles causes hundreds ofreported envenomations accidents each year Varioushypotheses have been proposed to explain how spe-ciTHORNc characteristics such as environmental factors andhabits of the human population have contributed tothis infestation of spiders The presence of extensiveurban green areas throughout the city has been sug-gested as a factor because these areas may serve as asource of spiders that disperse to buildings or as asource of food for spiders present in houses althoughthe occurrence of spiders in vegetation around build-ings has not been fully assessed Fischer (1996) stud-ied the phenology ofL intermedia inEucalyptus sp anexotic tree with loose bark and many hollows andcavities In contrast the use of native trees has notbeen studied Human habits such as the accumulationof dumps and objects as well as certain characteristicsof the houses (wooden constructions with a base-ments and cellar) also can favor occupation by thesespiders

Knowledge of the environmental preferences ofLoxosceles is extremely important for understandingthese infestations by the spiders and for developing

effective campaigns to protect against loxoscelism Inthis study we investigated the environment and sub-strata used byLoxosceles in urban forests and buildingsin Curitiba and determined the substrate preferenceof these spiders

Materials and Methods

Urban Forests Six parks were selected to evaluatethe distribution of Loxosceles in urban forests (Table1) All microhabitats (vegetation and buildings)present in the urban forests were inspected Buildingsin the parks and the anthropic environment weresubdivided into indoor and outdoor habitats In thevegetated areas spiders were collect in 25-m2 plots at100-m intervals along a transect on park trails Theloose bark cavities and hollows up to 2 maboveground were examined in all native and exotictrees in each 25-m2 plot as were the crevices of de-caying logs and the cavities and spaces among rootsand beneath rocks The presence of Loxosceles andtheir vestiges (exuviae egg sacs dead spiders bodyparts and abandoned webs) were recorded wheneverencountered We also inspected buildings such as mu-seums warehouses ofTHORNces and libraries as well asoutdoor dumps Spiders exuviae egg sacs and otherAraneae were collected from all available substratafrom November 1997 to July 1998Anthropic Environment Spiders were collected in

the houses of people who claim to have been bitten byLoxosceles in collaboration with Dr Marlene Enters ofthe 24-h service health unit of the Albert Sabin Hos-pital and the Center for Toxicological Informationassociated with the Parana State General OfTHORNce forHealth The collections were made from June to Au-gust 1998 in60housesat randompoints throughout thecity based on reported accidents and residents per-mission to search in their houses The spiders and theirvestigeswerecollected indoors andoutdoors(inback-yards and around the houses) cellar and basementswere not inspected Because of the different dimen-sions and amount and variety of substrata we stan-dardized the collection method in an effort to sample1 min per square meter First the area of the room wasmeasured and the search time was calculated Thetime spent capturing the spiders was not included inthe timed period The inspection was always done ina clockwise direction starting from the entrance to the

Table 1 Urban forests studied to assess the use of microhabitats by L intermedia and L laeta in Curitiba

ParkPark totalarea(m2)

Forestarea(m2)

Distance (km) and directionfrom center of town

Vegetation

Capao da Imbuotildea 42417 34800 7 East Forest of Araucaria imbuotildea andnative szligora

Heinhard Maack 78000 NA 12 Souterast Forest remains of AraucariaIguaccedilu 8264316 530000 20 Southeast Gallery forest and capon forestBarreirinha 275380 200000 14 North Capon forest with THORNve natural

lakesBarigui 14000000 NA 5 North Secondary forestJardim Botanico 278000 66022 8 East Secondary forest

NA area not available

September 2005 FISCHER AND VASCONCELLOS-NETO MICROHABITATS OF Loxosceles 757

room The substrata their sequence of occurrenceand the presence of spiders were recorded on taperecorder Outdoors trees and dumps were inspectedusing the same sampling procedure Piles of construc-tion material were considered as a group of sampleunits and were measured separately from the otheroutdoor sources Spiders were weighed and preservedin 70 alcohol The spidersOtilde weight was used as anindicator of habitat quality and of prey availabilityThe length of leg I in live and dead spiders and ofexuviae was used as an indicator of size

For analyses of favorable substratum for occupationby Loxosceles the indoor and outdoor objects weregrouped according to their composition The indoorcategories included wood paper plastic cloth metalas well as parts of the building such as the szligoor thewall behind pictures and corners The outdoor cate-gories included ceramic products (tiles bricks andpaving stones) asbestos (tiles) and wood Each ob-ject was a sampling unit The number of spiders (liveor dead) exuviae egg sacs and abandoned webs wasrecorded for each object

The frequencies of L intermedia and L laeta on thesubstrata and objects were expressed relative to thenumber of live and dead spiders (females males andjuveniles) visualized spiders (spiders seen but notcollected) and their vestiges (egg sacs exuviae andwebs) The category ldquosingle spiderrdquo indicated a singlespider without any vestiges and was considered anindicator of momentary refuge A series of exuviaeaccompanied or not by the corresponding spider wasconsidered as an occurrence The weight of spidersand size of the spiders and exuviae the distance to theclosest neighbor (between two spiders between aspider and an exuvium and between two exuviae)and the web area were compared between indoor andoutdoor sites in urban parks and residences for theunderstanding of the space used by a spider Thenumber of exuviae inside egg sacs collected in urbanparks and houses was assessed to determine whetherthere were differences in the fecundity of the twopopulations Adults juvenile and exuviae of L inter-media and L laeta are very easy to differentiate notcommitting the identiTHORNcation of the vestiges regis-tered without the spider Other families of Araneaepresent in the substrata used by Loxosceles also wereregistered or collected

Voucher specimens are deposited in Arachnologicalcollection Dr Vera Regina von Eicksted in section ofpoisonous arthropods of Immunologic Production andResearch Center (SESA-PR) Piraquara Parana Bra-zilStatistical Analysis To determine whether L inter-media and L laeta preferred speciTHORNc substrata theobserved frequencies of these spiders were comparedwith the expected frequencies based on the relativefrequencies of the different substrata A 2 test wasused to compare the frequencies and YatesOtilde correla-tion was used when the expected proportion in one ofthe classes was 5 The frequencies of males femalesand juveniles and of the speciTHORNc objects in each sub-stratum also were compared using these same testsThe weights sizes distances and average number ofspiders and exuviae per substratum were comparedusing the nonparametric KruskalETHWallis (H) andMannETHWhitney (U) tests because the samples did nothave a normal distribution even after transformations(StatSoft 2005)

Results

UrbanForests andUrbanResidences In the forests1775 m2 of vegetation was inspected but no live Lox-osceles or vestiges were found However Loxoscelesand their vestiges were found in buildings (indoors)and under construction material (outdoors) L inter-media was found in six parks and L laeta in only one(Table 2) We recorded 212 substrata with spidersandor vestiges from which 295 spiders (60 females31 males and 204 juvenile) and 238 exuviae werecollectedL intermedia occurred in 58 (97) of the 60 houses

inspected and L laeta occurred indoors in four oldwooden houses (67) L intermedia was recordedindoors and outdoors whereas only one male L laetawas captured on a tile outdoors (Tables 3 and 4) Inhouses where L laeta was present we only found Lintermedia outsideSubstrata with Spiders and Exuviae L intermedia

did not occur randomly in the six substrata it was mostcommon on wood and on paper [2

(5) 1299 P 0001] Outdoors asbestos was used preferentially[2

(2) 169 P 0001] L laeta also was also morefrequent on paper (Fig 1a) [2

(5) 673 P 0001]

Table 2 Substrata with L intermedia and L laeta in urban forests

Park

Capao Maack Iguaccedilu Barreirinha Barigui Botanico

Plots 7 12 10 14 17 11Area (m2) 175 300 250 350 425 275Trees 90 482 147 551 325 504Decaying logs 61 65 9 64 91 74Spider in forest 0 0 0 0 0 0Spiders in dumps 0 NA 17 L intermedia 104 L intermedia 28 L intermedia 42 L intermediaSpiders in buildings 12 L laeta

1 L intermedia42 L intermedia 24 L intermedia 8 L intermedia NA 17 L intermedia

Table shows total number of plots the area inspected and the number of trees and decaying logs examined as well as the number and speciesof Loxosceles collected in dumps (construction material around buildings) and inside buildings NA not available

758 JOURNAL OF MEDICAL ENTOMOLOGY Vol 42 no 5

The distribution of exuviae of L intermediawas notrandom on the six types of substrata there was apreference for wood and paper [2

(5) 1599 P 0001] Outdoors there was a prevalence on wood[2

(1) 156P 0001] (Fig 1b) whereas forL laetathere was a prevalence on paper (Fig 1b) [2

(5) 281 P 0001]Females Males and Juveniles For both species

there was a prevalence of juveniles [L intermedia2

(1) 2154 P 0001 and L laeta 2(1) 43 P

0001] Females and juveniles of L intermedia and Llaeta occurred in different frequencies on the varioussubstrata whereas males of L intermedia showed sim-ilar frequencies on the various substrata (Table 5)

Of the total number of spiders recorded only 35were single spiders with the remainder occurringwith other spiders or with vestiges [2

(1) 546 P 0001] The frequency of single females and juvenilesofL intermediawas different in the substrata whereasthe frequency of single males did not differ among thesubstrata For L laeta only single juveniles differed(Table 5)

Of the 41 dead spiders collected 29 were L inter-media(38 females 103 males and 517 juveniles)and 12 were L laeta (seven juveniles) (Table 5)Single Exuviae and Sequential Series Of the exu-

viae collected 13 corresponded to single exuviae

most of which were occurred with Loxosceles andorother exuviae [2

(1) 414 P 0001] The fre-quency of single exuviae ofL intermediawas larger onpaper indoors and on asbestos outdoors The largestfrequency of single exuviae for L laeta was on paperHowever the sequential series of exuviae of L inter-media was greater on wood indoors and outdoors(Table 5) The average number of exuviae for L in-termedia in the sequential serieswas2508(n125range 2ETH6) and that for L laetawas 26 02 (n 13range 2ETH4) There were no intra- or interspeciTHORNc dif-ferencesAverage Number of Spiders and Exuviae per Sub-stratum The average density of L intermedia and Llaeta was 14 097 (n 351 range 1ETH10) and 13 097 (n 99 range 1ETH8) spiders per substratum re-spectively Those densities were not signiTHORNcantly dif-ferent (U 140625 P 02) nor were there differ-ences among the substrata (L intermedia H 68 P05 and L laeta H 12 P 08) (Table 6) Theaverage number of exuviae per substratum was 22 28 (n 204 range 1ETH32) for L intermedia and 25 22 (n 39 range 1ETH10) forL laetawith no differencebetween the species (U 3674 P 02) For L laetathe average number of exuviae did not differ amongsubstrata whereas the average number for L inter-media (H 141 P 001) was greater on wood

Table 3 Absolute numbers of inspected substrata in houses with L intermedia substrata with occurrence (spiders andor vestiges)spiders and exuvia and numbers of spiders and exuvia (single and sequential series) collected indoors and outdoors of the 60 inspectedhouses

GroupObjects inspected

()aObjects with occurrence

()bObjects with spiders

()bObjects with exuvia

()bNo of spiders

()aNo of exuvia

()a

Wood 2239 (404) 202 (9) 122 (54) 73 (33) 194 (511) 223 (68)Paper 702 (127) 111 (158) 67 (95) 39 (56) 99 (261) 64 (195)Plastic 651 (117) 32 (49) 33 (51) 19 (29) 43 (113) 16 (49)Cloth 454 (82) 21 (46) 17 (37) 6 (13) 21 (55) 6 (18)House 1072 (193) 83 (77) 15 (14) 12 (11) 17 (45) 19 (58)Metal 429 (77) 31 (72) 3 (07) 0 6 (16) 0

Total indoors 5547 480 (86) 257 (46) 149 (27) 380 328Wood 35 (47) 8 (228) 5 (143) 7 (20) 9 (74) 15 (126)Asbestos 68 (92) 23 (338) 18 (264) 12 (176) 23 (19) 16 (134)Ceramic 638 (861) 110 (172) 71 (11) 36 (56) 89 (735) 88 (739)

Total outdoors 741 141 (19) 94 (127) 55 (74) 121 119

a Percentage of the total number in each analysisb Percentage of total for the corresponding substratum

Table 4 Absolute numbers of inspected substrata in houses with L laeta substrata with occurrence (spiders andor vestiges) spidersand exuvia and number of spiders and exuvia (single and sequential series) collected indoors and outdoors of the 60 inspected houses





()bNo of spiders

()aNo of exuvia

()a

Wood 249 (491) 55 (221) 41 (165) 19 (76) 46 (374) 57 (542)Paper 67 (132) 28 (418) 31 (463) 11 (164) 46 (374) 24 (228)Plastic 32 (63) 7 (219) 5 (156) 0 5 (41) 0Cloth 45 (89) 4 (89) 9 (20) 1 (22) 10 (81) 2 (19)House 83 (164) 27 (325) 13 (157) 8 (96) 16 (13) 22 (209)Metal 31 (61) 2 (64) 0 0 0 0

Total indoors 507 123 (243) 99 (195) 39 (77) 123 105Asbestos 68 (92) 0 0 0 0 0Ceramic 638 (861) 1 (0016) 1 (0016) 0 1 0

Total outdoors 741 1 1 (013) 0 1 0



Fig 1 Abundance of spiders and exuvia indoors and outdoors in 60 houses (a) Relative frequency of L intermedia andL laeta (white bars) and expected values (black bars) (b) Relative frequency of exuvia (single and sequential series) of Lintermedia and L laeta (white bars) and expected values (black bars) The observed and expected frequencies for eachsubstratum were compared using the 2 test P 005 NS not signiTHORNcant

Table 5 Total number of females (F) males (M) and juveniles (J) of single and dead spiders collected and of spiders seen as well asnumber of single exuvia and of sequential series of exuvia of L intermedia and L laeta indoors and outdoors in Curitiba

Species SubstratumTotal

Singlespiders

Deadspiders Spiders

seenSingle

exivium

Sequentialseries ofexiviaF M J F M J F M J

L intermediaIndoors Wood 36 14 118 12 5 43 6 1 5 26 22 61

Paper 21 7 68 5 2 20 2 1 2 3 15 17Plastic 9 4 26 3 2 9 0 0 2 4 9 6Cloth 2 2 15 1 0 2 0 1 0 2 6 4

Outdoors House 5 0 9 0 1 11 3 0 3 3 5 1Metal 1 1 3 0 0 0 0 0 0 1 0 0Wood 0 0 9 0 0 1 0 0 1 0 3 6Ceramic 12 4 69 6 2 26 0 0 1 4 18 28Asbestos 6 0 17 3 0 7 0 0 1 0 8 2

L laetaIndoors Wood 10 4 28 6 1 10 0 1 2 4 7 7



The observed frequencies were compared with the expected frequencies based on the relative frequencies of the different substrata (indoorsand outdoors) by using the 2 test

Values signiTHORNcantly different at P 005


(indoors) and on wood and ceramic surfaces (out-doors) than on cloth (Table 6)

The average weight of L intermedia differed be-tween spiders collected indoors and those collectedoutdoors in homes and in urban parks with females(H 143 P 001) males (H 147 P 001) andjuveniles (H 116 P 001) collected outdoors inurban parks being the heaviest (Table 7) The lengthof leg I in female and juvenile L intermedia did notdiffer between spiders collected in houses and urbanparks (H 99 P 01 andH 047 P 09) whereasmales collected in parks were generally larger (H 17P 00001) (Table 8)

The weight or size of female (H 21 P 08 andH 5 P 04) and male (H 54 P 036 and H34 P 06) L intermedia did not differ among thesubstrata In contrast juveniles collected on parts ofhouses weighed less that those collected on other

substrates but did not differ in size (H 125 P 005and H 81 P 014)

The average size of the exuviae was 80 28 mm(n 759 range 209ETH158) with those ofL intermediacollected outdoors in forests being larger than thosecollected outdoors around houses (H 164P 005)(Table8)Therewerenodifferences in the sizesof theexuviae collected on different substrata indoors (H28 P 06)Distances among Spiders The average distance

among individuals of L intermedia was 152 15 cm(n 67 range 1ETH70) The spacing of L intermedia inbuildings in the parks was greater than outdoors in theparks (U 665 P 001) and around houses (U 125 P 005) (Table 9) The average distance be-tween L intermedia and an exuvium was 101 134cm (n 91 range 0ETH81) with the distance outdoorsin urban parks being smaller than indoors in parks

Table 6 Average number of spiders and exuvia for L intermedia and L laeta per substratum indoors and outdoors in Curitiba

SubstratumL intermedia L laeta

Spiders Exuvia Spiders Exuvia

Indoors Wood 15 1a (122 1ETH10) 29 4a (73 1ETH32) 11 04a (41 1ETH2) 27 25a (19 1ETH10)Paper 14 08a (67 1ETH5) 17 01ab (39 1ETH5) 16 17a (31 1ETH8) 2 17a (11 1ETH7)Plastic 13 07a (33 1ETH4) 17 13ab (19 1ETH5) 1a (n 5)Tissue 14 01a (17 1ETH5) 1b (n 6) 11 03a (9 1ETH2)House 11 03a (15 1ETH11) 15 12ab (12 1ETH5) 12 06a (13 1ETH3) 27 17a (8 1ETH5)

Outdoors Wood 18 08a (5 1ETH3) 21 18a (7 1ETH6)Asbestos 13 06a (18 1ETH3) 13 06ab (12 1ETH3)Ceramic 12 05a (70 1ETH3) 23 18a (36 1ETH9)

Values are the mean SD The number of substrata and the range are shown in parentheses Means within a column followed by the sameletter are not signiTHORNcantly different (P 005 MannETHWhitney U test)

Table 7 Average weight (milligrams) of female male and juvenile L intermedia and L laeta collected indoors and outdoors aroundhouses and in forests

Species Local Female Male Juvenile

L intermedia House indoors 667 28a (74 34ETH137) 486 155a (28 27ETH827) 14 14a (239 05ETH762)House outdoors 686 35a (18 25ETH1514) 485 18ab (4 235ETH537) 142 147a (95 04ETH653)Park indoors 709 251ab (16 356ETH1255) 712 19ab (8 472ETH1013) 225 249b (41 09ETH1385)Park outdoors 90 329b (44 30ETH160) 757 33b (23 30ETH160) 197 16b (73 09ETH782)

L laeta House indoors 923 506 (30 218ETH235) 735 482 (6 324ETH1582) 19 16a (80 17ETH75)House outdoorsPark indoors 178 79a (14 10ETH40)Park outdoors


Table 8 Average size (millimeters) (length of leg I) of female male and juvenile L intermedia and L laeta collected indoors andoutdoors around and urban parks

Species Local Female Male Juvenile Exuvium

L intermedia House indoors 132 19a (74 103ETH188) 147 17a (28 124ETH175) 68 29a (239 21 137) 8 2a (484 29ETH144)House outdoors 126 16a (18 10ETH15) 13 13a (4 116ETH14) 71 27a (95 29ETH13) 73 26ab (149 21ETH124)Park indoors 129 14a (16 97ETH156) 172 15b (8 15ETH20) 69 3a (41 28ETH115) 86 31ab (81 29ETH158)Park outdoors 136 15a (44 107ETH18) 167 23b (23 13ETH21) 69 29a (149 29ETH128) 88 32b

L laeta House indoors 156 26 (30 122ETH22) 206 2 (6 19ETH23) 83 35a (80 29ETH206) 9 3 (126 28ETH152)House outdoorsPark indoors 71 22a (14 2ETH6) 3 (n 4)Park outdoors

Values are the mean SD The number of records and the range are shown in parentheses Means within a column followed by the sameletter are not signiTHORNcantly different (P 005 Mann-Whitney U test)


(U 154 P 005) and also smaller than that insidehouses andoutside aroundhouses(U1475P005and U 1165 P 005) (Table 9)

The average distance between exuviae of L inter-mediawas 83 115 cm (n 210 range 0ETH74) and wassmalleroutsidecomparedwith insidehouses(U694P 001) and indoors in urban park (U 3195 P 001) (Table 9)

The average area of L intermediawebs was 1057 1567 cm2 (n 220 range 2ETH1404) with those builtindoors houses being greater than those built outdoorsaround houses (U 890 P 005) (Table 9)

The average number of exuviae present in L inter-media egg sacs in houses and urban parks was 365 171 (n 20 range 15ETH88) and 379 214 (n 22range 6ETH100) respectively These values were notsigniTHORNcantly differentOther Araneae FamiliesWe recorded eight fami-

lies of spiders in the substrata frequently used byLoxosceles (Table 10) The frequencies of these fam-ilies varied among houses and urban parks with Phol-cidae [2

(1) 343P 0001] being the most frequentin houses Theridiidae occurred exclusively in housesand Scytodidae was most frequent in parks [2

(1) 532 P 0001] Indoors in houses Pholcidae andTheridiidae were more frequent [2

(1) 60P 0001and 2 125 P 0001] whereas Salticidae domi-nated outdoors [2

(1) 10 P 001] In parks theScytodidae was more frequent outdoors [2

(1) 61P 0001] whereas indoors only Pholcidae and Scy-todidae were found (Table 10)

Wall pictures [2(1) 283 P 0001] were the

preferred object in the ldquowoodrdquo group which showed

more sampling units with spiders andor vestiges of Lintermedia There were no differences in the ldquopaperrdquogroup for both species Wall pictures were present in933 of the houses with an average of 103 picturesper house of which 16 per house had spiders andorvestiges Cardboard boxes were found in all of thehouses with an average of 84 boxes per house and 15boxes with spiders andor vestiges Ceramic tiles werefound in only 217 of the backyards and an averageof 284 tiles was inspected per house a mean of 16 tilesper house had vestiges andor spiders

Discussion

In this study L intermedia and L laeta were asso-ciatedmainlywithbuildings andwere rare in thewildHowever these spiders occurred in isolated foci onnon-native trees close to the study area Fischer(1996) observedL intermediaonEucalyptus sp a treewith loose bark and many crevices and hollows thatprovided favorable microhabitats for these spidersLoxosceles spiders also occupied small spaces formedby rocks and tree roots In the United States 81 of Lreclusa (Hite et al 1966) and in Peru 69 of L rufipes(Delgado 1966) were collected beneath or betweenrocks Curitiba is characterized by long humid periodsthat do not favor the occupation of similar microhabi-tats because of the sensitivity of these spiders to hu-midity (Delgado 1966 EskaTHORN et al 1977) In the urbanforests of Curitiba Loxosceles did not occur in treesbut it was found indoors and outdoors in all parks Itis unclear whether these spiders have abandoned theirnatural habitat to colonize buildings or whether theyinitially colonized buildings The lack of spiders andvestiges in the wild reinforces the second hypothesisGorham (1968) and EskaTHORN et al (1977) reported arelationship between temperature and habitat for Lreclusa Depending on the site the spiders occurredonly in the wild (high temperatures) only insidebuildings (low temperatures) or in both (suave tem-peratures) In Curitiba where the average annualtemperature is 165C (Maack 1981)Loxoscelesoccurspreferentially indoors The predominance of Loxosce-les indoors is well documented (Hite et al 1966 Vil-larroel et al 1972 Whitcomb and Wallace 1972 Sche-none and Lentoja 1975 Lowrie 1980) althoughspecies such asL rufipes are more frequent in the wild(Delgado 1966) The limited variation in indoor tem-

Table 9 Average spacing (centimeters) among spiders between spiders and exuvia and between exuvia as well as the area of the webs(square centimeters) of L intermedia and L laeta indoors and outdoors around houses and in urban parks

Species Spider spider Spider exuvium Exuvium exuvium Web area

L intermediaHouse indoors 17 20ab (27 1ETH70) 10 96a (23 1ETH32) 95 14a (129 0 74) 107 154a (76 9ETH912)House outdoors 8 24a (4 5ETH10) 86 67a (17 0ETH20) 39 69b (22 0ETH20) 903 248b (31 2ETH1404)Park indoors 196 11b (18 1ETH40) 137 19a (23 1ETH81) 84 86a (52 0ETH34) 172 161c (21 20ETH630)Park outdoors 93 74a (18 2ETH27) 4 55b (23 0ETH27) 73 12ab (18 0ETH51) 107 130a (58 8ETH702)L laeta

House indoors 31 268 (50 2ETH12) 266 225 (5 3ETH49) 75 144 (12 0ETH49) 728 678 (34 6ETH270)

Values are the mean SD The number of samples and the range are shown in parentheses Means within a column followed by the sameletter are not signiTHORNcantly different (P 005 MannETHWhitney U test)

Table 10 Numbers of other spiders families found in the sametypes of substrata as Loxosceles indoors and outdoors aroundhouses and in urban parks

Spider familyHouses Urban parks

Indoors Outdoors Indoors Outdoors

Scytodidae 9 6 1 64Pholcidae 70 1 5 1Salticidae 6 23 0 19Clubionidae 6 8 0 18Theridiidae 22 4 0 0Ctenidae 2 0 0 4Lycosidae 0 3 0 0Filistatidae 1 0 0 0

Total 116 45 6 106


perature favors the occupation and reproductive suc-cess of Loxosceles (Delgado 1966 Schenone and Len-toja 1975) According to Fischer (1996) this factor isespecially important in Curitiba where climatic os-cillations are frequent The synanthropic habit of thegenus agrees with the similarity between the substratapresent inside buildings and that of the natural habitatAccording to Gertsch (1967) all Loxosceles speciescan adapt to domestic habitats Bucherl (1961) statedthat the invasion of buildings results from locomotionof the spider at night However spiders may arrive atresidences by a passive mechanism Although passivetransport contributes to the dispersion of these spi-ders the active colonization of buildings (Delgado1996 Huhta 1972 Fischer 1996) can lead to the in-festation of houses close to a focus

Of the 60 houses inspected 97 had Loxosceles ortheir vestiges Schenone et al (1970) reported a rateof infestation of 295 for rural and urban buildings inChile average of 84 spiders per house In Curitiba theaverage number of spider per house was 108 (outcellar and basements) The greater frequency of Lintermedia than L laeta in homes (802) and urbanparks (959) agreed with Fischer (1994) who re-ported that L intermedia accounted for 90 of theLoxosceles spiders caught in Curitiba However de-spite the predominance of L intermedia in Curitibathe THORNrst record of this species in the Colecao Arach-nologica Rudolf Bruno Lange (Museu de Historia Nat-ural Capao da Imbuia Parana Brazil) the principalcollection of spiders in Curitiba dates only from 1964(Fischer 1994)L laeta predominated indoors and did not coexist

with L intermediaThe association of L laetawith oldwooden houses and its more sedentary habits (Fischer2002) suggest that this species was associated with oldbuildings before the introduction of L intermedia Asa result L intermedia did not establish populationswhere L laeta was resident However the frequentmovement of L intermedia away from the webs al-lowed new buildings to be colonized by this speciesBucherl (1961) is the only author to have describedthe occurrence of L laeta outdoors the other recordsmention only the occupation of buildings (Galiano1967 Levi and Spielman 1964 Schenone et al 1970Huhta 1972 Villarroel et al 1972) The limited dis-persal of L laeta was been noted in populations in-troduced into urban (Levi and Spielman 1964 Huhta1972) and rural (Schenone et al 1970) regions and hasbeen attributed to low external temperatures (Huhta1972) and the large distances between houses (Sche-none et al 1970) In Curitiba both species apparentlypreferred the same environmental conditions al-though L intermedia had the widest distributionwhich further suggests a link with speciTHORNc character-istics This hypothesis is based on studies of the hunt-ing behavior web defense the resistance of spiderlingsto starvation and the rates of cannibalism (Fischer2002)

The fact that the two Loxosceles species were notdistributed randomly in the substrata suggested thatthese spiders selected the substratum for colonization

with paper wood and construction material havingmore spiders and vestiges Although paper was not themost abundant substratum it was used preferentiallyby both species Wood also was used as a refuge andas place for growth mainly by L intermedia Bothpaper and wood have been reported to colonizationby Loxosceles (Bucherl 1961 Levi and Spielman 1964Hite et al 1966 Delgado 1966 Huhta 1972) Construc-tion material left outdoor attracts large populationsLoxoscelesWhen left undisturbed for a long time thismaterial serves as an important center from whichspiders can colonize surrounding buildings Bucherl(1961) stated that construction material provided amore favorable environment than the natural habitatbecause of the dark well-ventilated interior and theabundant food supply

Intra- and interspeciTHORNc differences inszliguenced theoccupation of substrata Males occurred to a similarextent on all substrata in agreement with their ten-dency to wander (Levi and Spielman 1964 Huhta1972) The preference of females for colonizing paper(both species) and asbestos (L intermedia) suggestedthat those sites provided favorable conditions for re-production The occurrence of juveniles and exuviaeon paper (both species) and wood (L intermedia)indicated that theses substrata offered an appropriatemicroclimate enough feed for growth and a safe shel-ter for ecdysis However these substrata also wereused as a temporary shelter as shown by greater num-ber of juveniles compared with exuviae on plastic(both species) and cloth and metal (L intermedia)and the presence of single spiders and exuviae onpaper (both species) The results obtained outdoorssuggested emigration and recent colonization Theoccurrence of emigration (wood) was deduced basedon large number of juveniles and exuviae and theabsence of adults whereas recent colonization of theasbestos was suggested by the large number of juve-niles and females and few exuviae

The presence of more than one exuvium per site andoften of a series of exuviae of different sizes suggestedsite partitioning and residence in the same placethroughout postembryonic development A similarpattern also was recorded for L reclusa (Hite et al1966) and L rufipes (Delgado 1966) Despite the ten-dency of juveniles to wander (Levi and Spielman 1964Huhta 1972) dispersion is probably more commonwith dense populations and during competitive inter-actions (Fischer 2002) The emigrant then establishesresidence upon THORNnding an empty favorable place Thesmall number of spiders per substratum (14) and thesimilar spacing suggest that territorial mechanismsmay determine occupation (Bucherl 1961 Fischer2002)

The greater weight of females males and juvenilesof L intermedia in urban parks may reszligect the prox-imity to vegetation and the availability of prey Ac-cording to Morse and Fritz (1982) the biomass offemales is an excellent indicator of the choice andquality of the feeding site The greater weight of fe-males in urban parks was not reszligected in a largernumber of exuviae per egg sac suggesting that both


environments offered good conditions for feeding andreproductive success The greater size of urban parkmales was probably related to an additional ecdysisthat according to Fischer and Vasconcellos-Neto(2005a) produces signiTHORNcantly larger individuals andreszligects the abundance of food

The occupation of urban buildings by Loxosceles isfavored by passive transport and can result in theintroduction of non-native species (Waldron and Rus-sell 1967 Gorham 1968 Huhta 1972 Southcott 1976Borkan et al 1995) with the success in adapting beingrelated to the spidersOtilde tolerance of low humidity andlong periods without water or food (Delgado 1966Hite et al 1966 Gorham 1968 Whitcomb and Wallace1972 EskaTHORN et al 1977 Greenstone and Bennett 1980Lowrie 1980 1987) Schenone et al (1970) associatedthe infestation of L laeta in Chile with characteristicsof the houses and the social level of the populationand Gertsch (1967) reported that the degree of in-festation was inversely proportional to the degree ofcleanliness However in the current study we asso-ciated the presence of Loxosceles on potential sub-strata with the success of occupation In this case thespiders may be controlled through careful manage-ment of the substrata

The lack of vestiges of a previous occupation inurban forests around Curitiba indicated that both spe-cies primarily occupied urban buildings where theyencountered ideal conditions for proliferation In ad-dition to providing stable climatic conditions build-ings also offered various substrata with thermal isola-tion and a texture suitable for displacement webTHORNxation ecdysis mating and oviposition Spiders thatemigrate from foci (eg cellar basements and con-struction material) or are introduced passively intohouses by humans frequently THORNnd favorable sites forsurvival and reproduction

Acknowledgments

We thank Emanuel Marques-da-Silva and Centro deProducao e Pesquisa de Imunobiologicos-SESA-PR for gen-eral support and use of laboratory space equipment and staff(Joel e Jorge Milton) as well as Marlene Entres Secretaria daSaude do Estado do Parana Prefeitura Municipal de CuritibaThis work was supported by Curso de Pos-Graduacao emZoologia Universidade Federal do Parana and Conselho Na-cional de Desenvolvimento CientotildeTHORNco e Tecnologico Grantno 14131994-4 JV-N was supported by Conselho Nacionalde Desenvolvimento CientiTHORNco e Tecnologico Grant no30053994- and by BIOTAFAPESP Grant no 9905446-8

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Bucherl W 1961 Aranhas do genero Loxosceles e loxos-celismo na America Ciencia Cultura 13 213ETH224

Bucherl W 1962 Aranhas do genero Loxosceles e ldquoloxos-celismordquo na America do Sul Mem Inst Butantan 30167ETH186

CaneseA 1972 Loxosceles rufescens (Dufour 1820) en IslaPucu del Departamento de la Cordillera (Paraguay) RevParag Microb 7 83ETH85

Delgado A 1966 Investigacion ecologica sobre Loxoscelesrufipes (Lucas) 1834 en la region costera del Peru MemInst Butantan 33 683ETH688

Eskafi FM J L Frazier R RHocking andB R Norment1977 Inszliguence of environmental factors on longevity ofthe brown recluse spider J Med Entomol 14 221ETH228

Fischer M L 1994 Levantamento das especies do generoLoxosceles Heinecken amp Lowe 1832 no municotildepio deCuritiba PR Estudos Biol 38 67ETH86

Fischer M L 1996 Biologia e Ecologia de Loxosceles inter-media Mello-Leitao 1934 (Araneae Sicariidae) no Mu-nicotildepio de Curitiba PR MS thesis Universidade Federaldo Parana Curitiba Brazil

Fischer M L 2002 Utilizacao do Habitat por Loxoscelesintermedia Mello-Leitao 1934 e L laeta (Nicolet 1849)no municotildepio de Curitiba PR Uma abordagem experi-mental sobre aspectos ecologicos e comportamentaisPhD dissertation University of Parana Curitiba Brazil

Fischer M L and J Vasconcelos-Neto 2005a Develop-ment and life tables of Loxosceles intermedia Mello-Le-itao 1934 (Araneae Sicariidae) J Arachnol (in press)

Fischer M L and J Vasconcelos-Neto 2005b The preyand predators of Loxosceles intermediaMello-Leitao 1934(Araneae Sicariidae) J Arachnol (in press)

Galiano M E 1967 Ciclo biologico y desarrollo de Loxos-celes laeta (Nicolet 1849) Acta Zool Lilloana 23 431ETH464

Gertsch W J 1967 The spider genus Loxosceles in SouthAmerica Bull Am Mus Nat Hist 136 121ETH182

Gorham R 1968 The brown recluse spider EnvironHealth 31 138ETH143

Greenstone M T and A F Bennett 1980 Foraging strat-egy and metabolic rate in spiders Ecology 61 1255ETH1259

Hite M J W J Gladney J L Lancaster Jr and W HWhitcomb 1966 Biology of brown recluse spider Ar-kans Agric Exp St Bull 711 2ETH26

Huhta V 1972 Loxosceles laeta a venomous spider estab-lished in a building in Helsinki Finland and notes on someother synantropic spiders Ann Entomol Fenn 38 152ETH156

LeviHW andA Spielman 1964 The biology and controlof the South American brown spider Loxosceles laeta(Nicolet) in a North American focus Am Trop MedHyg 13 132ETH136

Lowrie D C 1980 Starvation longevity of Loxosceles laeta(Nicolet) (Araneae) Entomol News 9 130ETH132

Lowrie D C 1987 Effects of diet on the development ofLoxosceles laeta (Nicolet) (Araneae Loxoscelidae) JArachnol 15 303ETH308

Maack R 1981 GeograTHORNa fotildesica do Estado do Parana 2nded Livraria Jose Olympio Rio de Janeiro Brazil

McDaniel J N andD T Jennings 1983 Loxosceles reclusa(Araneae Loxoscelidae) found in Maine USA J MedEntomol 20 316ETH331

MadonMB andREHall 1970 First record ofLoxoscelesrufescens (Dufour) in California Toxicon 8 91ETH92

Morse D H and R S Fritz 1982 Experimental and ob-servational studies of patch choice of different scales bythe crab spider Misumena vatia Ecology 63 172ETH182

Newlands G C Isaacson and C Martindale 1982 Loxos-celism in the Transvaal South Africa Trans R Soc TropMed Hyg 75 610ETH615

Rinaldi IMP L C Forti and A A Stropa 1998 On thedevelopment of the brown spider Loxosceles gaucho


Gertsch (Araneae Sicariidae) the nympho-imaginal pe-riod Rev Bras Zool 14 697ETH706

Russell F EWGWaldron andM BMadon 1969 Bitesby the brown spiders Loxosceles unicolor and Loxoscelesarizonica in California and Arizona Toxicon 7 109ETH117

Schenone H and T Lentoja 1975 Notas sobre la biologotildeay distribucion geograTHORNca de las aranas del genero Loxos-celes Bol Chil Parasitol 30 27ETH29

SchenoneHARojasHReyes FVillarroel andG Suarez1970 Prevalence of Loxosceles laeta in houses in centralChile Am J Med Hyg 19 564ETH567

Southcott R V 1976 Spiders of the genus Loxosceles inAustralia Med J Aust 1 406ETH408

StatSoft 2005 Electronic statistic textbook (httpwwwstatsoftcomtextbookstathomehtml)

Unzicker J D 1972 The THORNrst record of the spider Loxos-celes rufescens (Dufour) in Illinois Entomol News 83119ETH120

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venomations in a Kansas home implications for bite di-agnoses in nonendemic areas J Med Entomol 39 948ETH951

Vetter R and S P Bush 2002 Reports of presumptivebrown recluse spider bites reinforce improbable diagno-sis in regions of North America where the spider is notendemic Clin Infect Dis 25 442ETH445

Villarroel F H Schenone A Rojas andH Sanhueza 1972Distribucion por estado de desarrollo y sexo deLoxosceleslaeta capturadas en la zona central de Chile Bol ChilParasitol 26 59ETH60

Waldron W G and F E Russell 1967 Loxosceles reclusain southern California Toxicon 5 57

WhitcombWH andHKWallace 1972 The occurrencein Florida of the recluse spider Loxosceles reclusa Ento-mol News 83 57ETH59

Received 15 March 2005 accepted 15 May 2005


POPULATION AND COMMUNITY ECOLOGY

Microhabitats Occupied by Loxosceles intermedia and Loxosceles laeta(Araneae Sicariidae) in Curitiba Parana Brazil

MARTA LUCIANE FISCHER1 AND JOAO VASCONCELLOS-NETO2

J Med Entomol 42(5) 756ETH765 (2005)

ABSTRACT A survey was done of the environments and substrata occupied byLoxosceles intermediaMello-Leitao 1934 and Loxosceles laeta (Nicolet 1849) (Araneae Sicariidae) in urban woods andanthropic constructions in Curitiba In total 2099 trees 364 decaying logs as well as stones and rootsbuilt-up areas and wasteland in six urban parks and 60 residences were inspected In total 1775 m2

of vegetation was inspected but spiders and their vestiges were collected only in and around buildingsin urban parks and residencesL intermediawas more common thanL laetaand occurred both indoorsand outdoors whereas L laetawas more common indoors in wooden houses The two species did notoccur in the same microhabitats although both preferred paper wood and construction materialsSpiders collected in urban parks were heavier than those collected in residences although only malescollected in urban parks were larger than those from residences The lack of vestiges indicative of aprevious occupation in the urban parks suggested that both species occupied primarily the anthropicenvironment where they found numerous substrata that offered thermal isolation and suitableconditions for web THORNxation ecdysis and reproduction

KEY WORDS anthropic environment habitat selection loxoscelism

THE GENUS Loxosceles (Araneae Sicariidae) is cosmo-politan and synanthropic with two species Loxosceleslaeta(Nicolet 1849) andLoxosceles rufescens(Dufour1820) having a worldwide distribution In Brazil thegenus is represented by nine speciesLoxosceles similisMoenkhaus 1898Loxosceles amazonicaGertsch 1967Loxosceles adelaida Gertsch 1967 Loxosceles puortoiMartins Knysak amp Bertani (2002) Loxosceles anoma-laAlvares Rodrigues amp De Maria 2004 LoxoscelesgauchoGertsch 1967 Loxosceles hirsutaMello-Leitao1931 L laeta and Loxosceles intermediaMello-Leitao1934 (Gertsch 1967) with the latter four species oc-curring in the Brazilian state of Parana L laeta and Lintermedia account for 10 and 90 respectively of theLoxosceles spiders found in Curitiba the capital ofParana (Fischer 1994) L laeta is native to westernSouth America probably Argentina or Chile and hasbeen transported for several countries (eg theUnited States Finland and Australia) whereas L in-termedia is found only in Argentina and southern andsoutheastern Brazil (Gertsch 1967)

OutdoorsLoxosceles spiders occur in many habitatsincluding rock cavities beneath rocks and beneathloose bark in hollow trees and abandoned termitenests in crevices of decaying logs under leaf litter incaves and grottos in rock crevices along the shorelineand under shaded gravel in dry areas (Bucherl 1962

Delgado 1966 Hite et al 1966 Galiano 1967 Gertsch1967 Russell et al 1969 Schenone and Lentoja 1975Newlands et al 1982 Borkan et al 1995 Rinaldi et al1998) Hite et al (1966) described the bluffs of north-western Arkansas as one of the probable primary hab-itats of L reclusa because they provided excellentenvironmental conditions at high and low tempera-tures

Indoors Loxosceles spiders occur preferentially indark dry undisturbed places such as wooden or card-board boxes broken and irregular szligoors behind pic-tures or objects beneath or behind furniture drawersclothing and stored paper and in corners (Bucherl1961 1962 Levi and Spielman 1964 Hite et al 1966Galiano 1967 Gertsch 1967 Gorham 1968 Schenoneet al 1970 Huhta 1972 Whitcomb and Wallace 1972Schenone and Lentoja 1975 Rinaldi et al 1998) Thesespiders also are found in old tires and dumps (Hite etal 1966) and in piles of construction material aroundbuildings (Bucherl 1961 1962 Gertsch 1967 Canese1972 Rinaldi et al 1998) Borkan et al (1995) reportedan infestation of L rufescens in orchard litter andcardboard boxes placed around the bases of trees tosoften the fall of ripe fruit

Few studies have evaluated the factors that favorthe occupation of buildings even for medically im-portant species of Loxosceles Schenone et al (1970)assessed the prevalence of L laeta in residences inChile whereas others (Hite et al 1966 Delgado 1966Vetter and Barger 2002) reported the preferentialoccurrence in a speciTHORNc room or construction withoutspecifying the substratum present The habits of Lox-

1 Nucleo de Estudos do Comportamento Animal Departamento deBiologia CCBS Pontifotildecia Universidade Catolica do Parana CuritibaPR Brazil

2 Departamento de Zoologia Instituto de Biologia UniversidadeEstadual de Campinas Campinas SP Brazil

0022-2585050756ETH0765$04000 2005 Entomological Society of America










Forestarea(m2)


Vegetation










Results






(5) 673 P 0001]


Park











(1) 2154 P 0001 and L laeta 2(1) 43 P













()bNo of spiders

()aNo of exuvia

()a



Total outdoors 741 141 (19) 94 (127) 55 (74) 121 119







()bNo of spiders

()aNo of exuvia

()a



Total outdoors 741 1 1 (013) 0 1 0






Singlespiders

Deadspiders Spiders

seenSingle

exivium















































Discussion











Total 116 45 6 106














Acknowledgments


References Cited




















































Forestarea(m2)


Vegetation










Results






(5) 673 P 0001]


Park











(1) 2154 P 0001 and L laeta 2(1) 43 P













()bNo of spiders

()aNo of exuvia

()a



Total outdoors 741 141 (19) 94 (127) 55 (74) 121 119







()bNo of spiders

()aNo of exuvia

()a



Total outdoors 741 1 1 (013) 0 1 0






Singlespiders

Deadspiders Spiders

seenSingle

exivium















































Discussion











Total 116 45 6 106














Acknowledgments


References Cited















































Results






(5) 673 P 0001]


Park











(1) 2154 P 0001 and L laeta 2(1) 43 P













()bNo of spiders

()aNo of exuvia

()a



Total outdoors 741 141 (19) 94 (127) 55 (74) 121 119







()bNo of spiders

()aNo of exuvia

()a



Total outdoors 741 1 1 (013) 0 1 0






Singlespiders

Deadspiders Spiders

seenSingle

exivium















































Discussion











Total 116 45 6 106














Acknowledgments


References Cited
















































(1) 2154 P 0001 and L laeta 2(1) 43 P













()bNo of spiders

()aNo of exuvia

()a



Total outdoors 741 141 (19) 94 (127) 55 (74) 121 119







()bNo of spiders

()aNo of exuvia

()a



Total outdoors 741 1 1 (013) 0 1 0






Singlespiders

Deadspiders Spiders

seenSingle

exivium















































Discussion











Total 116 45 6 106














Acknowledgments


References Cited














































Singlespiders

Deadspiders Spiders

seenSingle

exivium















































Discussion











Total 116 45 6 106














Acknowledgments


References Cited















































































Discussion











Total 116 45 6 106














Acknowledgments


References Cited
























































Discussion











Total 116 45 6 106














Acknowledgments


References Cited























































Acknowledgments


References Cited














































Acknowledgments


References Cited


























































Documents

Microhabitats Occupied by Loxosceles intermedia and Loxosceles laeta (Araneae: Sicariidae) in Curitiba, Paraná, Brazil