H. W. Levi.
The American Spiders of the Genera Styposis and Pholcomma (Araneae, Theridiidae).
Psyche 71(1):32-39, 1964.

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THE AMERICAN SPIDERS OF THE GENERA
STYPOSIS AND PHOLCOMMA
(ARANEAE, THERIDIIDAE)*
BY HERBERT W. LEVI
Museum of Comparative Zoology, Harvard University Several new species have been discovered since publication only a few years ago of a paper on Styposis (Levi, 1960). One of these new species, 5'. selis, gives a clue to the relationship of the genus. The features characterizing Styposis are the ectally-facing embolus of the male palpus, and reduced or absent anterior median eyes. In only one other theridiid genus are there six-eyed species: Comaroma Bertkau, found in south-central Europe, Japan, and the western United States. However, the different structure of Comaroma genitalia and the large colulus suggest that the eye reduction evolved independently. The ectally-facing embolus is found also in one species of the genus Pholcomma (P. hirsuta Emerton, Levi 19571, members of which also frequently have the anterior median eyes reduced in size, and the colulus replaced by two setae; but, unlike most species of Styposis, Pholconuna species usually have denticles on the posterior margin of of the chelicerae. In our revision of theridiid genera (Levi and Levi, 1962) it was suggested that there might be species intermediate be- tween Styposis and Pholcom7na. However the female of 8. rancho here described has the epigynum similar to that of some Chilean Anelosinzus species, a theridiid genus of larger spiders. But the epigynum of S. selis from southern Brazil resembles that of the Chilean Anelosimus, and furthermore the complexity of the male palpus also suggests that it belongs to the species group of Anelosimus endemic in Chile. The chelicerae have teeth on the posterior margin, as in Aneloiiimus and Pholconima species, a feature uncommon in the Theridiidae. But unlike Chilean Anelosimus (Levi, 1936), 5. selis has only six eyes. Before the discovery of S. selis, it was thought that the ectally facing embolus in some Chilean Anelosimus (Levi, 1963), was a unique character, evolved independently. It is now evident that Styftosis is intermediate between Pholcomma and the Chilean Anelosiinus, the most abundant theridiid spiders in Chile, although Styposis generally lacks posterior teeth on the chelicerae. Styposis clausis has a rough cheliceral surface facing the fang and a carina ending in an indistinct tooth (Fig. 10). Previously Styposis was known only from America; now a small *Manuscript received by the editor December 3,1963. Pachc 71:32-19 (1964). hup Yipsychc einclub orgi71/71-012 html



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19641 Levi - Styposis and Pholcomm 33
specimen has been found in New Guinea, collected with a Berlese funnel in rain forest. The specimen is short-legged, pigmented and has eight eyes. It is the only Styposis specimen having habitat infor- mation.
The two species described here from South America are placed in Pholcoma tentatively, awaiting the discovery of males and additional specimens.
I would like to thank Dr. W. J. Gertsch of the American Museum of Natural History; Dr. A. Collart and J. Kekenbosch of the Institut Royal des Sciences Naturelles, Brussels; and Prof. M. Vachon of the Museum National d'Histoire Naturelle, Paris (MNHN), for the loan of collections; and Prof. M. Biraben, director of the Museo Argentino de Ciencias Naturales, Buenos Aires, for the loan of a specimen from the La Plata Museum. This investigation was sup- ported in part by Public Health Service Research Grant AI-01944, from
I a.
1 b.
2a.
2 b.
3a-
3b.
4a.
4b.
5a.
5b.
6a.
6b.
7a.
7b.
the National Institute of Allergy and Infectious Diseases. Key to American Styposis species
With six eyes ( I 960, fig. I ; Fig. 8) ........................................ 2 With eight eyes or six eyes and pigment spots in place of anterior medians ( I 960, fig. 5, 10, I 8, 24) ............................................ 4 First patella-tibia less than one and one-half times carapace length; southern Brazil ............................................ sells sp. n. First patella-tibia more than twice carapace length ................ 3 Male with first patella-tibia more than three times carapace length (Fig. 12) ; epigynum with a transverse knob (1960, .................................................... fig. 3) ; Panama
clausis Levi
Male with first patella-tibia two and one-half times carapace ........
length ; female unknown ; Nicaragua
nicaraguensis Levi
Abdomen wider than long (1960, fig. 10) ; Panama ................ ....................................................................... chickeringi Levi Abdomen larger than wide or subspherical ............................ 5 Carapace sclerotized, with reticulate raised pattern ................ 6 Carapace lightly sclerotized, smooth .................................... 7 Carapace widest behind middle, rounded behind ( 1959, fig. 18) ; ....................................
Nicaragua to Venezuela flavescens Simon
Carapace widest in middle, drawn out behind with a short stalk ....................................
( 1960, fig. 24) ; Panama
scleropsis Levi
Posterior median eyes separated by their diameter (1959, fig. ...............................
27) ; southwestern United States
ajo Levi
.................
Posterior median eyes their radius or less apart 8




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19 641 Levi - Styposis and Pholcom7na 35 8a. Anterior lateral eyes separated by one diameter (1959, fig. 5) ; .............................................................. Venezuela rancho Levi
8b. Anterior lateral eyes separated by about one and one-half dia- ...............................
meters (Fig. I ) ; Equador
colorados sp. n.
Styposis colorados sp. n.
Figures 1-3
Holotype. Male from 35 km northwest of Santo Domingo de 10s Colorados, Pichincha, Ecuador, 22 Dec. 1958 (A. M. Nadler), in the American Museum of Natural History. The specific name is a noun in apposition after the type locality. Description. Carapace, sternum, reddish brown. Legs grayish brown. Abdomen whitish. Diameter of anterior median eyes less than radius of other eyes. Anterior median eyes less than one diameter apart, touching laterals. Posterior median eyes their radius apart, almost touching laterals. Legs short. A small transverse, sclerotized plate anterior to spinnerets on venter. Between plate and spinnei-ets, two setae replace colulus. Total length 1.0 mm. Carapace 0.51 mm long, 0.47 mm wide. First femur, 0.52 mm; patella and tibia, 0.52 mm; metatarsus, 0.39 mm; tarsus, 0.25 mm. Second at el la and tibia, 0.41 mm; third, 0.35 mm; fourth, 0.48 mm. Diagnosis. The embolus is on the ectal side of the palpus as in other Styposis (Figs. 2, 3), but is easily visible, and the species is thereby distinguished from 5. rancho in which the embolus is difficult to see.
Styposis selis sp. n.
Figures 4-9
Holotype.
Male from Nova Teutonia, lat 27' I I'S, long 52' 23'W, Santa Catarina, Brazil, July 1955 (F. Plaumann) in the Institut Royal des Sciences Naturelles, Brussels. The specific name is an arbitrary combination of letters.
Description. Carapace, sternum, legs yellow; abdomen whitish with Figs. 1-3. Styposis colorados sp. n. 1. Male Carapace. 2. Left p'alpus, ventral view. 3. Left palpus, ectal view. Figs. 4-9. S. selis sp. n. 4. Palpus. 5. Male. 6. Female genitalia, dorsal view. 7. Epigynum. 8. Female. 9. Left female chelicera, posterior view. Figs. 10-12. S. clausis Levi. 10. Left Female chelicera, posterior view. 11. Palpus. 12. Male.
Figs. 13-14. S. rancho Levi. 13, Female genitalia, dorsal view. 14, Epigynum.




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36 Psyche [March
sclerotized part yellowish. Ducts and seminal receptacles black and showing through epigynum. Carapace of female longer than wide (Fig. 8), that of male almost circular and quite high (Fig. 5). Six eyes in two clumps touching each other. Posterior median eyes one diameter apart. Abdomen longer than wide. Abdomen of male with a lightly sclerotized ring around spinnerets. In female, first leg equals fourth in length; first leg longer than fourth in male. Total length of female 1.3 mm. Carapace 0.55 mm long, 0.50 mm wide. First femur, 0.48 mm; patella and tibia, 0.55 mm; metatarsus, 0.26 mm; tarsus 0.30 mm. Second patella and tibia, 0.43 mm; third 0.38 mm. Fourth femur, 0.48 mm; patella and tibia, 0.58 mm; metatarsus, 0.26 mm; tarsus, 0.31 mm. Total length of male 1.2 mm. Carapace 0.58 mm long, 0.54 mm wide. First femur, 0.54 mm; patella and tibia, 0.64 mm; metatarsus, 0.31 mm; tarsus, 0.32 mm. Second patella and tibia, 0.47 mm; third, 0.42 mm; fourth, 0.60 mm. Diagnosis. The coiling of the heavily sclei-otized ducts of the epigynum, and the Anelosimus-like palpus separate this species from 5. clausis. The six eyes and small size separate the species from Chilean Anelosinzus.
Records. Q $2, c?
paratypes collected with holotype, July 1955 and August 1957.
Styposis rancho Levi
Figures I 3-14
Sfyposis rancho Levi, 1960, Psyche, 66; IS, figs. 5-6, 8. Male holotype from
Rancho Grande, Venezuela, in the American Museum of Natural History.
Description of female. Coloration and eyes as in male. Abdomen subtriangular, as wide as long, widest anterior. Epigynum very transparent with dark ducts showing through (Fig. 14). The female has much longer legs than the male. Total length 1.6 mm. Carapace 0.71 mm long, 0.66 mm wide.
First femur, 1.72 mm; patella and
tibia, 1.80 mm; metatarsus, 1.30 mm; tarsus, 0.52 mm. Second patella and tibia, I .30 mm ; third, 0.67 mm; fourth, 1.03 mm. Records. Venezuela. Distrito Federal: Caracas, Dec. I 887-Feb. I 888, $2 (E. Simon, MNHN) . Aragua: Tovar, Jan.-Feb. I 888, Q (E. Simon, MNHN).
Styposis clausis Levi
Figures I 0- I 2
Styposis clausis Levi, 1960, Psyche, 66: 15, figs. 1, 2, 4, 9. Female holotype
from Forest Reserve, Panama Canal Zone, in the Museum of Com- parative Zoology.




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19 641 Levi - Styposis and Pholcomma 3'7 Descri+tion of rtzale. The animal is entirely yellow-white without pigment; abdomen whitish.
Anterior lateral eyes more than one
diameter apart. Posterior median eyes a little less than a diameter apart, touching laterals. 'Total length I*? mm. Carapace 0.69 mm long, 0.69 mm wide. First femur, 1-97 mm; patella and tibia, 2.22 mm; metatarsus,
1.64 mm; tarsus, 0.60 mm. Second patella and tibia I -72 mm ; third, 0.84 mm ; fourth I. I I mm. The male differs from the female by having a narrower abdomen. Records. Panama: El Valle, ?, d, July 1936 (A. hl. Chickering). Key to American Pholcomna species
Carapace yellow-white ................................................................ 2 Carapace brown ........................................................................ 3 Male palpus with a spring-like coiled embolus (1957, figs. 35- 37) ; epigynum with anterior depression (1957, figs. 32-33) ; Pennsylvania to North Carolina ........................ barnesi Levi hlale palpus with a short embolus (1957, figs. 28-30) ; female unknown ; North Carolina coast ................................ carota Levi Ducts anterior to seminal receptacles (1957, figs. 24-25) ; male palpus with embolus facing ectally ( 1957, figs. 19-21) ; eastern United States to Wisconsin, hlississippi, Florida ........................ .......................................................................... hirsut,um Emerton Ducts posterior of seminal receptacles; males unknown; South ........................................................................................ America 4
Ducts, in ventral view, looping (Fig. 16) ; Catamarca, Argentina .................................................... nzicropz~nctatunz ( Mello-Leitiio) Ducts, in ventral view, straight (Fig. 18) ; hfinas Gel-ais, .................................................................... Brazil mantinum sp. n*
Pholcomma hirsutum Emerton
Pholcommu lzirsutum Emerton, 1882, Trans. Connecticut Acad. Sci., 6~29, PI. 6, fig. 6, 9, 6'. Two female, one male syntypes from New Haven, Connecticut in the Museum of Comparative Zoology, examined. -Lev;, 1957, Trans. Amer. Micros. SOC., 76:110, figs. 19-27, 48, map (hirmta). Note. The gender of the generic name is neuter. Pholcomma micropunctatum (Afello-Leitiio) Figures I 5- I 6
Dipoena micropunctata Mello-Leitao, 1941, Rev, Mus. La Plata, n. s., 2:142, fig. 37, 9. Female holotype from La Vifia, Catamarca, Argentina in the Museo de La Plata, examined.




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Psyche
[March
Figs. 15-16. "Pho1comma" mict-opunct'atum (Mello-Leit20). 15. Epigynum cleared. 16, Epigynum.
Figs. 17-18. ~'PholcommaJ' mantinurn sp. n. 17. Epigynum cleared. 18. Epigynum-
Descrifition. Sclerotized areas brown; abdomen gray with four white spots on anterior end of dorsum* Carapace, legs sclerotized. Carapace rather high. Eyes subequal in size. Anterior medians two- thirds diameter apart, touching laterals. Posterior median eyes one- third diameter apart, one-quarter from laterals. Chelicerae weak) pointed on both ends, without teeth. Fang large, curved, almost one- half total height of chelicerae. Abdomen with bases of setae sclerotized and some scattered
small sclerotic spots. A sclerotic ring around pedicel and around spinnerets. Colulus with two setae. Total length 2.0 mm. Carapace 0.71 mm long. First patella and tibia 0.93 mm. The male being unknown, placement of this species is uncertain. Since the female has only two seminal receptacles (Fig. 15) it cannot be a Di#ocna and is probably not Em-yopis. It differs from other Pholcomma by lacking teeth on the chelicerae. It is possible that the specimen lacks lungs and belongs to the family Symphytognathidae. Pholcomma mantinurn sp. n.
Figures I 7-1 8
fIoZotype. Female from Diamantina, Minas Gerais, Brazil in the American Museum of Natural History. The specific name is an arbi- trary combination of letters.




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19643
Lmi - Styposis and PhoZconznza
39
Descrifltion. The whole spider is brownish, the abdomen is lighter on venter. The carapace is sclesotized. The posterior median eyes are largest, the anterior median eyes smallest. The anterior median eyes are two-thirds their diameter apart, almost touching laterals. The postei-ios median eyes are almost touching, less than one-quarter diameter from laterals. The cheliceme are very small, the shape of an equilateral triangle, and lack teeth. The abdomen is suboval with setae coming from sclerotized round spots on dorsum. The sides seem folded and there
is a sclerotized ring around the spinnerets. The colulus is replaced by two setae. Total length 1.5 mm. Carapace 0.62 mm long, 0.56 mm wide. Second patella and tibia 0.66 mm; third 0.56 mm. Fourth femur, 0.66 mm, patella and tibia, 0.88 mm. The specimen is in pool- physical condition. Diagnosis. 2'his specimen is quite close to P. micro~unctat,urn (Mello-Leitiio). The ducts of the genitalia are shorter (Figs. 17, 18). Along with P. nzicro~uncta~um this species may belong to the family Symphytognathidae; its placement in Pholco?n?na is tentative. LEVI, H. W.
1957. The North American Spider genera Paratheridula) Tekellina) P/zolcomma and Arch~rius (Araneae, Theriidae). Trans, Amer. Micros. SOC., 76: 105-115.
1960. The spider genus Styposis (Araneae, Theridiidae). Psyche 66: 13- 19.
1963. The American spiders of the genus Ane/osimus (Araneae, Theri- diidae). Trans. Amer, Micros. Soc., 82: 30-48. LEVI, H. I%'. and L. R. LEVI
1962.
The genera of the spider family Theridiidae. Bull. MUS. Comp. Zool., 127: 1-72.




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