Herbert W. Levi.
The Spider Genera Stemmops, Chrosiothes, and the New Genus Cabello from America.
Psyche 71:73-92, 1964.

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THE SPIDER GENERA STEMMOPS, CHROSIOTHES, AND THE NEW GENUS CABELLO FROM AMERICA
BY HERBERT W. LEVI
Museum of Comparative Zoology, Harvard University While examining types of theridiid spiders in European museums, 1 discovered that the genus Theridiotis Levi, 1954, is a synonym of Chrosiothes Simon. In the meantime, additional species have been found of Chrosiothes, and also of Ste?nmops, revised in 1955. In addition, in Simon's large collections from Venezuela, a theridiid spider was found that could not be placed in any known genus. A National Science Foundation Grant (G-4317) made possible a trip to examine types. I am grateful also for the hospitality of Prof. M. Vachon of the Museum National d'Histoire Naturelle, Paris; and Dr. G. Owen Evans, Mr. E. Browning and Mr. K. Hyatt of the British Museum (Natural History) in London. Without the unfailing help in the loan of specimens of Prof. Vachon, Dr. W. J. Gertsch of the American Museum of Natural History (AMNH), Dr. R. V. Chamberlin of the University of Utah (UU), and Mrs. D. Frizzell (Dr. H. Exline) of Rolla, Missouri, this paper would not have been possible. I would like to thank Fr. Chr~santhus who gave advice on Latin specific names. A National Institutes of Health Grant (AI-01944) facilitated completion of the paper. Stemmops 0. P.-Cambridge, 1894 (January), Biologia Centrali-Americana, Araneidea, 1: 125. Type species by monotypy S. bicolor 0. P.-Cambridge. The name Stemmops, according to Bonnet (1958, Bibliographia Arane- orum, 2: 4150), is of masculine gender.
Description.
Eyes very large, close together, usually in a black area. Legs very strong and short. Fourth leg sometimes longer than first, fourth patella and tibia 1.5 to 1.6 times carapace length. Abdo- men longer than wide; dorsoventrally flattened. Colulus replaced by
two short setae. Abdomen usually with a light spot above spinnerets. Diagnosis. Separated from other genera that bear two colulus setae by relatively large eyes, close together, and short stout legs. Stemmops is similar to the African Coscinida and differs only by having colulus setae. It is probable that Coscinida Simon, 1894, a name several months younger than Stemmops, has to be synonymized after more species have been examined (Levi and Levi, 1962). Distribution. Steinmops is known only from America. Most Pwfif 71:7J-9i (1964). hitp//psyche ralclub orgi7JJ71-07-1 him)



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74 Psyche [June
species have been described and illustrated in a previous paper (Levi, 1955)
I a.
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Males ........................................................................................ 2 Females ...................................................................................... 9
Embolus coiled (Fig. 9) ; Panama ........................ servus sp. n. Embolus not coiled .................................................................. 3 Palpal embolus short, framed by outline of bulb or cymbium in ventral view ........................................................................ 5 Palpal embolus long, partly covering cymbium margin in ven- tral view .................................................................................. 4 Radix with a hook ( 1955, figs. I 7, 18) ; Geo'rgia, Gulf states, Mexico to Panama, Bahama lsl. ........ bicolor 0. P.-Cambridge ................ Radix with a spine ( 1955, fig, 19) ; Mexico Una Levi
Embolus filament thick; half as wide as area surrounded by ............
embolus (1955, fig. 20) ; Yucatan, Tabasco, Honduras ............................................................................ cambridgei Levi Embolus filament fine, one-third as wide as area surrounded by embolus (Figs. I, 3, 6) ............................................................ 6 Carapace sclerotized, brown ; area between lateral and median eyes not black (Fig. 3) ; Minas Gerais, Brazil ........ vicosa sp. n. Carapace soft, yellowish; area between lateral and median eyes .......................................................................................... black '7
Distal portion of embfolus almost straighlt, pointed distally ........ ( I 955, fig. 22) ; eastern United States possibly to Panama ........................................................................ ornatus ( Bryant) Embolus describing a half circle, its tip pointing ectally (Figs. I, 6) ......................................................................................... 8 Area enclosed by embolus in ventral view 1,onger than wide (Fig. I ) Venezuela ........................................ subtilis ( Simon) Area enclosed by embolus in ventral view subcircular (Fig. 6) ; Southern Mexico' to Panama ........................ questa Levi Epigynum with triangular median dark area (Fig. 5) ; Minas Gerais, Brazil ........................................................ vicosa sp. n. Epigynum otherwise ................................................................ I 0 Epigynum with a median depression or dark marks (Figs. .................................................................................... 15, 18) I I
Epigynum otherwise, with an indistinct transverse lip (Fig. ........................................................ 12), Panama servus sp. n.
11a. A median dark mark (Fig. 15)
or a median dark septum in




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Levi - Spider Genera 75
depression (1955, fig. 34) ; ducts with small loop anterior to seminal receptacles ( 1955, fig. 33 ; Fig. 14) ........................ 12 Epigynum and ducts otherwise ........................................... I 3 Duct lomop anterior of seminal receptacles on their ectal side .......................................
(Figs. I 4, I 5) ; Panama
nzellus sp. n.
Duct loops anterior to seminal receptacles on their mesa1 side ........
(1955, fig. 33) ; southern Mexico to Panama questa Levi
Depression containing shadows of sclerotized areas ( 1955, figs. 32, 36) ............................................................................ 14 Depression otherwise ........................................................... 15 Ducts looping anterior ; seminal receptacles behind depression ( I 955, fig. 35) ; Georgia, Gulf states, Mexico to Panama, ........................................ Bahama Isl. bicolor 0. P.-Cambridge
Duct barely anterior of seminal receptacles; seminal receptacles anterior to depression ( 1955, fig. 3 I ) ; Yucatan, Tabasco, Honduras ........................................................ cambridge! Levi Depression bordered anterior (1955, fig. 30) ; eastern United ........................................................................................ States 16 Depression bordered on sides or posterior ............................ I7 Connecting ducts coiled (Fig. 17) ; anterior border of depres- ............
sion ventral to seminal receptacles (Fig. 18), Panama ................................................................................... oms sp. n. Connecting ducts not coiled, bent (1955, fig. 29) ; anterior border of depression posterior to seminal receptacles ( I 955, fig. 30) ; eastern United States .................... ornatus (Bryant) Depression bordered on sides ( 1955, fig. 28) ; Tamaulipas ................................................................................ victoria Levi Depression otherwise ............................................................ 18 Duct coiled, heavily sclerotized ( 1955, fig. 26) ; Mexico ........ ........................................................................................ Una Levi Duct almost straight, lightly sclerotized ( 1955, fig. 23) ; Pana- ............................................................................ ma cryptus Levi
Stemmops bicolor 0. P.-Cambridge
Stemmops bicolor 0. P.-Cambridge, 1894, Biologia Centrali-Americana, Araneidea, 1: 125, pi. 17, fig. 5,
8. Male holotype from Teapa, Tabasco,
Mexico in the British Museum.-Levi, 1955, Ann. Ent. Soc. Amer., 48: 338, figs. 14, 17, 18, 35, 36, 9, 8. Distribution.
Georgia, Gulf states, Mexico, to Panama and Ba- hama Isi.
Additional records. Panama. Boquete (A. M. Chickering) . Pan- ama Canal Zone. Summit, (A. M. Chickering) ; Barro Colorado Island (A. M. Chickering) ; near Pedro Miguel (A. M. Chickering).



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19 641
Levi - Spider Genera
77
Sternmops ornatus (Bryant)
Euryopis ornata Bryant, 1933, Bull. Mus. Comp. 2001. 74: 172, figs. 2, 3, 6. Male holotype from Meridian, Lauderdale County, Mississippi in the Museum of Comparative Zoology.
Stemmops ornata,-Levi, 1955, Ann. Ent. Soc. America, 48: 341, figs. 16, 21, 22, 29, 30, 9, 8.
Distribution. New Jersey, Ohio, Missouri, Georgia to Mississippi. Additional record. Missouri, Johnson Co. : Warsensburg, 29 June I 962, ? (W. Peck).
Stemmops subtilis (Simon), n. comb.
Figure I
Coscinida subtilis, 1895, Ann. Soc. ent. France, 64: 137. Male holotype from
San Estaban, [Carabobo], Venezuela in the Museum National d'Histoire Naturelle, Paris, examined.
Stemmops vicosa sp. n.
Figures 2-5
Type. Male holotype from Viqosa, Minas Gerais, Brazil, 6 July 1933 (Hambleton), in the American Museum of Natural History. The specific name is a noun in apposition after the type locality. Description. Carapace brown. Eyes ringed by black but otherwise little black between eyes. Sternum, legs yellow-brown. Abdomen whitish without pattern or marks, lighter above' spinnerets in female. Carapace high and sclerotized. Eyes subequal in size. Anterior median eyes one-third diameters apart, touching laterals. Posterior median eyes slightly less than their radius apart, two-thirds diameters from laterals. Eyes of female slightly farther apart. Anterior margin of chelicerae without teeth. Abdomen of female subtriangular, of male slightly wider in front than behind (Fig. 2). Colulus replaced by two setae.
Total length of female 1.6 mm. Carapace 0.54 mm long, Fig. 1. Stemmops subtiVts (Simon), left palpus. Figs. 2-5. 8. vicosa sp. n. 2. Male. 3. Palpus. 4. Female genitalia, dorsal -
view. 5. Epigynum.
Figs. 6-8. S. questa Levi. 6. Palpus. 7-8. Male. Figs. 9-12. S. servus sp. n. 9. Palpus. 10. Male. 11. dorsal view. 12. Epigynum.
Figs. 13-15. S. mellus sp. n. 13. Female. 14. Female -
view. 15. Epigynum.
Fies. 16-18. S. orsus sp. n. 16. Female. 17. Female Female genitalia,
genitalia, dorsal
genitalia, dorsal
c,
view. 18. Epigynum.




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78 Psyche [June
0.50 mm wide. First patella and tibia 0.60 mm; second 0.48 mm ; third 0.39 mm. Fourth femur 0.59 mm ; patella and tibia 0.7 I mm; metatarsus 0.44 mm. Total length of male 1.4 mm. Carapace 0.52 mm long, 0.58 mm wide. First femur 0.65 mm; patella and tibia 0.66 mm ; metatarsus 0.32 mm ; tarsus' 0.36 mm. Second patella and tibia 0.50 mm; third 0.39 mm; fourth 0.65 mm. Diagnosis. Genitalic structure (Figs. 3-5), brown carapace and absence of black eye area separate this species from 8. bicolor and others.
Record. $ paratype collected with holotype. Stemmops servus sp. n.
Figures 9-12
Type. Male holotype from Forest Preserve, Panama Canal Zone, 29 Jan. 1958 (A. M. Chickering) in the Museum of Comparative Zoology. The specific name is an arbitrary combination of letters. Description.
Female with carapace yellow, dusky on sides, eye region black, sternum gray, legs yellow, abdomen gray with white spot above spinnerets. Male with carapace dark brown, sternum black, palpi colorless light. First and second coxae black, third and fourth yellow-white; all trochanters yellow-white; other leg segments black, except proximal half of fourth femora yellow-white. Abdomen black with white spot above spinnerets. Carapace subcircular. Ante- rior median eyes slightly smaller than others, about two-thirds their diameter apart, touching laterals. Posterior median eyes one diameter apart, touching laterals. Total length of female 1 .2 mm. Carapace 0.5 mm long, 0.5 mm wide. First patella and tibia, 0.6 mm; second, 0.6 mm; third, 0.5 mm. Fourth femur, 0.6 mm; patella and tibia, 0.7 mm ; metatarsus, 0.4 mm ; tarsus, 0.3 mm. Total length of male I .o mm. Carapace, 0.5 mm long; 0.5 mm wide. First femur, 0.6 mm; patella and tibia, 0.7 mm; metatarsus, 0.4 mm; tarsus, 0.4 mm. Sec- ond patella and tibia, 0.5 mm; third, 0.4 mm ; fourth, 0.7 mm. The male and female have not been collected together. But the structure, particularly of the carapace and eye region, is very similar. The coloration, however, differs; the female is lighter. Diagnosis. The coiled embolus of the palpus (Fig. 9) separates this species from other Stemofis. The epigynum (Fig. 12) has no distinguishing marks and the ducts could be found only under a compound microscope (Fig. I i ) .
Records. Panama Canal Zone: Forest Preserve, Jan., Feb. 1958, $? (A. M. Chickering).




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19 641 Levi - Spider Genera 7 9
Stemmops questa Levi
Figures 6-8
Stemmops questa Levi, 1955, Ann. Ent. Soc. America, 48: 340, figs. 33, 34, 9. Female holotype from Chiapas, Mexico in the American Museum of Natural History.
Description. Male. Carapace yellow-white, eye region black, some median longitudinal gray pigment marks. Sternum, legs yellow- white. Abdomen gray with unpigmented yellow-white spot above spinnerets. Anterior median eyes slightly smaller than others, less than one-quarter diameter apart, touching laterals. Posterior median eyes less than one-quarter diameter apart, touching laterals. Total length 1.4 mm.
Carapace 0.7 mm long, 0.5 mm wide. First patella and tibia, 0.9 mm; second, 0.7 mm; third, 0.6 mm. Fourth femur, 0.8 mm; at el la and tibia, 1.0 mm; metatarsus, 0.5 mm; tarsus, 0.5 mm.
The embolus of the palpus is relatively short (Fig. 6). The male described here has not been collected with the female, but seems to match the female in general appearance and particularly in eye arrangement.
Natural history. Found in leaf mold in Panama. Distribution. Southern Mexico to Panama. Additional records. Panama. Boca Toro, Changuinola Dist., 18 Jan. 1925, 9 (F. R. Swift, AMNH). Panama Canal Zone: near Cocoli, 13 Jan. 1958, 6 (A. M. Chickering) ; Forest Preserve, Jan., Feb. 1958, (A. M. Chickering) ; Experimental Gardens, 10-14 July 1955, ? (A. M. Chickering) ; Pedro Miguel, 25 Aug. 1954, Q (A. M. Chickering) .
Stemmops mellus sp. n.
Figures I 3- I 5
Type. Female holotype from Barro Colorado Island, Panama Canal Zone, June-July 1934 (A. M. Chickering) in the Museum of Comparative Zoology. The specific name is an arbitrary combina- tion of letters.
Description. Carapace yellow-white, dusky on sides, with median dorsal gray marks. Sternum light with gray pigment and scattered small unpigmented spots. Legs yellow-white. Abdomen dorsum gray, light spot above spinnerets without pigment ; venter without pigment, almost whitish. Carapace subcircular (Fig. 13). Anterior median eyes smaller than other eyes, their radius apart, touching laterals. Posterior median eyes less than a quarter of their diameter apart, touching laterals. Total length 1.7 mm. Carapace 0.6 mm long,



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80 Psyche [June
0.6 mm wide. First patella and tibia, 0.8 mm; second, 0.6 mm; third, 0.6 mm. Fourth femur, 0.8 mm; patella and tibia, 0.9 mm; metatarsus, 0.5 mm; tarsus, 0.4 mm.
Diagnosis. This species can be separated from S. questa by the internal female genitalia (Fig. 14) and by the dark marks on the anterior of the seminal receptacles in the epigynum. The dark marks are toward the lateral side of the seminal receptacles in S. meZZus (Fig. 15) while they are median in S. questa. Record. Two juvenile paratypes collected with type. Stemmops orsus sp. n.
Figures I 6- I 8
Type. Female holotype from Forest Preserve, Panama Canal Zone, 28 Feb. 1958 (A. M. Chickering) in the Museum of Com- parative Zoology. The name is an arbitrary combination of letters. Description. Carapace yellow, dusky on sides and in center; eye region black.
Sternum dusky around edges ; legs yellow. Abdomen black with three pairs of white dorsal spots and a spot above spin- nerets (Fig. 16). Diameter of anterior median eyes almost half that of others. Anterior median eye's almost one diameter apart, touching laterals. Posterior median eyes one-quarter diameter apart, touching laterals. Total length 1.3 mm. Carapace 0.4 mm long; 0.4 mm wide. First patella and tibia, 0.5 mm ; second, 0.4 mm ; third, 0.4 mm. Fourth femur, 0.4 mm; patella and tibia, 0.6 mm; metatarsus, 0.2 mm; tarsus, 0.3 mm.
Diagnosis. Stenznzops orsus differs from 8. Una by having a trans- verse curved lip in the eyigynum (Fig. 18). It differs from S. ornatus, found in the eastern United States, by having the internal ducts coiled (Fig. 17).
Records. Panama. Boquete, 1-8 Aug. 1950, 2 $ paratypes (A. M. Chickering) .
Chrosiothes Simon
Chrosiothes Simon, 1894, Histoire Naturelle des Araignkes, 1: 521. Type species by original designation and monotypy: C. silvaticus Simon, 1894.
Theridiotis Levi, 1954, Trans. Amer. Micros. Soc., 73: 178. Type species by
original designation. Dipoena jocosa Gertsch and Davis. Description. Abdomen suboval, subtriangular or with humps on each side,
and often with characteristic coloration. Venter black, particularly anterior and above pedicel. Two minute setae replace colulus.
Legs sometimes noticeably thick, first or fourth the longest.



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19641 Levi - Spider Genera 81
Longest patella and tibia one to two times carapace length. Male very much smaller than female.
Epigynum with an indistinct oval depression; connecting ducts in most species characteristically coiled. The male palpus has the con- ductor absent or minute; the cymbium is uniquely modified to hold tip of long embolus.
Diagnosis. The coloration, the coils of the internal genitalia, the superficially simple structure of the palpus, and the above mentioned modification of the cymbium separate this genus from the related Episinus, Splntharus, Thwaites'ia and Anelosimus. Distribution. The genus is known only from the Americas. Misplaced species. Chrosiothes australis Simon, 1896, = Anelo- sirnus australis (Simon). C. porteri Simon, 1900 = Anelosimus australis (Simon).
Key to species of Chrosiothes
Abdomen with seven dorsal humps (Fig. 36), Mexico .... litus Abdomen with two or without humps .................................... 2 Abdomen with humps or abdomen as wide or wider than long ............................................................................................ 3 ~bdornen without humps, longer
Abdomen width equal to length
..... Abdomen longer than wide
Abdomen with anterior lateral
...................
Texas, Tamaulipas
than wide ............................ 8 ............
or wider than long 4
.............................................. 6 humps (1954, figs, 10, 19);
.................................. jocosus ............ Abdomen without humps, or humps anterior dorsal 5
Palpal embolus as long as circumference of bulb (1954, fig. 6) ; female abdomen with transverse stripes ( 1954, fig. 22) ; Tamaulipas to Honduras ................................................ tonala Palpal embolus shorter than bulb circumference (Fig. 19) ; female abdomen with two dark spots (Fig. 22) ; Arizona to Nayarit, Mexico ........................................................ portalensis ................ Abdomen humps anterior (Fig. 39) ; California iviei
............ Abdomen humps in middle or posterior of abdomen 7
........ Abdomen widest in middle (Fig. 30) ; Jamaica jamaicensis
Abdomen widest posterior ( 1954, figs. I I, 2 I ) ; Texas, northern Mexico ...................................................................... minusculus Abdomen widest in posterior half (1954, fig. 23) ; Veracruz, Mexico ....................................... - ................................. w agn eri ................................
Abdomen widest anterior or in middle
9
Abdomen suboval, rounded behind (1954, fig. 20) ; Utah, Colorado to central Mexico ............................................ chirica



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Abdomen subtriangular, pointed behind 10 ................................................................................... Females I I
..................................................................................... Males 14
Epigynum with small median depression, its width less than radius of seminal receptacle (Fig. 32) ; Est. Rio de Janeiro, Brazil ................................................................................ niteroi Width of depression equal to shorter seminal receptacle dia- ....................................................................................... meter 12
Depression bordered only anterior (Fig. 25) ; duct with only ....................
one loo'p (Fig. 24) ; Veracruz, Mexico
proxnmis
Depression bordered all around, or only on posterior (1954, .............................................................................. figs. 34, 36) 13
Dorsum of abdomen white with black spots; duct diameter near openings wider than duct near seminal receptacle (1954, ........
fig. 35) ; Veracruz, Mexico to Costa Rica goodnightorwn
Dorsum of abdomen purplish, duct diameter of equal width (1954, fig. 37) ; Florida, Mexico to Ecuador ............ silvaticus Cymbium outline subcircular in ventral view; embolus filament (except for tip) not supported by radix (1954, fig. 9) ; Vera- ..............................
cruz, Mexico to Costa Rica