Nyetnops, PLATNICK & LISE, 2007

PLATNICK, NORMAN I. & LISE, ARNO A., 2007, On Nyetnops, a New Genus of the Spider Subfamily Nopinae (Araneae, Caponiidae) from Brazil, American Museum Novitates 3595, pp. 1-12 : 4-9

Nyetnops , new genus

TYPE SPECIES: Nyetnops guarani , new species.

ETYMOLOGY: The generic name is an arbitrary combination of letters, masculine in gender because of the ending - ops.

DIAGNOSIS: Members of the genus can be separated from the previously known caponiid genera as follows: from Caponia Simon (1887) ,

Calponia Platnick (1993) , Diploglena Purcell (1904) , Caponina , Notnops Platnick (1994b) , Taintnops Platnick (1994b) , and Tisentnops Platnick (1994b) by the presence of subsegmented tarsi, from Nopsides by having only two eyes, from Nops by having normal, rather than greatly elongated, unpaired tarsal claws, from Tarsonops by having entire metatarsi and only two tarsal subsegments, and from Orthonops by lacking a metatarsal keel and a process extending from the intersegmental membrane between the metatarsi and tarsi of legs I and II.

DESCRIPTION: Small caponiids with carapace light orange, bearing paler yellow markings in labyrinthine arrangement (fig. 1), oval, widest at front of coxae III, only gradually narrowed anterior of eyes; pars cephalica elevated at rear (more so in males than in females), without elevated ocular tubercle; pars thoracica high anteriorly, steeply sloping posteriorly, with only very slight submarginal elevations opposite coxal bases, separated by very slight submarginal depressions opposite coxal interspaces; cuticle mostly smooth, with low sculpturing consisting of roughly hexagonal cells restricted to area of thoracic groove, with few long, dark setae in ocular area and on pars cephalica; thoracic groove obsolete; clypeus without pair of rounded elevations at lateral corners, almost three times as high as eyes. Two large, dark eyes separated by less than their diameter, posterior margins situated at about one–eighth of carapace length, united by oval ring of black pigment. Chelicerae with median lamina terminating in toothlike tip; distal half of median edge of paturon occupied by white membranous lobe; lateral surface flattened, with long series of stridulatory ridges (figs. 7, 8); pick for stridulatory ridges at base of prolateral side of palpal femur (figs. 3, 9). Endites (figs. 10, 11) light orange, wide, strongly convergent, not protuberant posteriorly, rounded distally, males with protuberant anterolateral corners (fig. 2), anterior surface distally with strong serrula consisting of single tooth row (fig. 12), proximally without strong setae originating from enlarged bases. Labium light orange, broad, triangular, fused to sternum along deep posterior groove. Sternum light orange, oval, cuticle glabrous, bearing scattered weak setae; cephalothoracic membranes with three weakly sclerotized epimeric sclerites dorsal of coxae I, II, and III plus IV; sternal margin rebordered, with long, triangular extensions reaching to middle of coxae II–IV and shorter intercoxal projections; epimeric sclerites not fused with sternal extenstions. Female palpal tarsus only very slightly expanded, without claw, with numer- ous long setae, including conspicuous, dense patch of setae prolaterally and dorsal pad of shortened setae. Leg formula 4123; legs orange, without spines, with many setae; cuticle ridged, granulate (fig. 23); metatarsi entire, without translucent median, longitudinal keel or distal, translucent, fan-shaped extension originating from intersegmental membrane (figs. 13, 14); tarsi subsegmented (fig. 14), proximal subsegment slightly longer than distal one; tarsi with three claws (figs. 15–18); paired claws with about 7–9 teeth, most distal of which are largest (tooth number varies among legs, and between pro- and retroclaw of each leg); unpaired claw without teeth, distinctly protruding from onychium. Tarsal organ exposed, with con- centric ridges (fig. 24); metatarsi with slit sense organs near depressed area bearing tiny, central pore (figs. 21, 22); trichobothria (figs. 19, 20) present on tibiae, metatarsi, and tarsi, their bases with semicircular rim bearing slight longitudinal ridges. Abdomen pale gray dorsally, with hairline pale markings, lighter ventrally, with two pairs of respiratory spiracles clustered around epigastric groove, tra- cheal arrangement unknown. Spinnerets in typical caponiid arrangement; judging from light microscopy only, anterior laterals apparently with single large major ampullate gland spigot and two smaller piriform gland spigots in female, male with only major ampullate gland spigot evident; posterior medians apparently with 3–5 long-shafted aciniform gland spigots, females with enlarged, posteriorly situated single wide spigot; posterior laterals with several aciniform gland spigots. Male palpal femur without dorsal tubercle; patella short; tibia not excavated ventrally, distal promargin with short row of stiff, pale setae; cymbium (figs. 29, 30) only slightly swollen, with distinct dorsal pad of short setae; palpal bulb longer than cymbium, distinction evident between bulb and embolus only by differences in cuticular surface (figs. 25–28). Internal female genitalia consisting of membranous, transverse anterior receptaculum bearing lateral sclerotized elements, without median receptaculum extending posteriorly (fig. 6).

DISTRIBUTION: Known with certainty only from southeastern Brazil.

Nyetnops guarani , new species

Figures 1–30

TYPES: Male holotype and female allotype from Fóz do Córrego Três Barras, Rio Guarani, Três Barras do Paraná, Paraná, Brazil (Feb. 24–Mar. 24, 1993; A. B. Bonaldo), deposited in MCN .

ETYMOLOGY: The specific name is a noun in apposition taken from the type locality.

DIAGNOSIS: The enormously elongated palpal bulb of males (figs. 3–5, 25–28) and the anteriorly excavated lateral epigynal sclerotizations of females (fig. 6) are diagnostic.

Male (holotype): Total length 3.27. Carapace 1.31 long, 1.22 wide, pale orange with pair of large, prominent, longitudinal lighter markings on elevated portion at rear of pars cephalica, in labyrinthine pattern elsewhere on carapace. Endites with distinctly protruding anterolateral corners. Abdomen with hairline pale markings. Palpal tibia with promarginal row of stiff setae; entire bulb enormously elongated (figs. 3–5, 25–28).

Female (allotype): Total length 3.46. Carapace 1.34 long, 1.18 wide. Coloration as in male. Endites without protruding corners. Internal genitalia with low sclerotized triangles situated near origin of posterior tracheae (fig. 6).

OTHER MATERIAL EXAMINED: BRAZIL: Parana´: Fóz do Córrego Três Barras, Rio Guarani, Três Barras do Paraná, Feb. 24–Mar. 24, 1993 (A. B. Bonaldo, MCN 23414, AMNH), 173; Foz do Rio Capoteiro, Pinhão , Oct. 25, 1991 (R. Pinto-da-Rocha, M. R. Lopes, MHCI), 13; Usina Hidrelétrica, Reserva Rio dos Touros , Pinhão , Feb. 22, 1992 (R. Pinto-da-Rocha, MCN 25919), 33 , Mar. 1992 (R. Pinto-da-Rocha, MHCI), 13; Usina Hidrelétrica, Ribeirão Estreito, Pinhão , Jan. 21– Feb. 1992 (R. Pinto-da-Rocha, MHCI), 33 , Mar. 1992 (R. Pinto-da-Rocha, M. Segalla, MCN 25918, 25920 ), 83. Rio Grande do Sul: Vicente Dutra , all pitfalls, T. F. Trescher : Jan. 8, 2006 (MCTP 19528), 33, 1♀, Jan. 23, 2006 (MCTP 19529), 153, 3♀, Feb. 7, 2006 (MCTP 19530), 73, Feb. 22, 2006 (MCTP 19531), 63, Mar. 9, 2006 (MCTP 19532), 93, 2♀. Santa Catarina: Nova Teutonia , Aug. 1957 (F. Plaumann, IRSN), 1♀ .

DISTRIBUTION: Southeastern Brazil.

Figures

Figs. 1, 2. Nyetnops guarani, new species, male cephalothorax and abdomen. 1. Dorsal view. 2. Ventral view.

Figs. 3–6. Nyetnops guarani, new species. 3. Left male palp, prolateral view. 4. Same, ventral view. 5. Same, retrolateral view. 6. Internal female genitalia, dorsal view.

Figs. 7–12. Nyetnops guarani, new species, male. 7. Chelicera, oblique anterior view. 8. Cheliceral striculatory ridges, oblique lateral view. 9. Stridulatory pick on palpal femur, prolateral view. 10. Endite, anterior view. 11. Endite, posterior view. 12. Serrula, oblique posterior view.

Figs. 13–18. Nyetnops guarani, new species, male. 13. Metatarsus and tarsus I, dorsal view. 14. Same, lateral view. 15. Claws of leg I, lateral view. 16. Same, detail. 17. Claws of leg IV, lateral view. 18. Setae accompanying claws of leg IV, lateral view.

Figs. 19–24. Nyetnops guarani, new species, male. 19. Metatarsus IV, dorsal view. 20. Trichobothrium from metatarsus IV, dorsal view. 21. Metatarsus I, slit sense organ and pore, dorsal view. 22. Same, detail of pore. 23. Cuticle, leg I, dorsal view. 24. Tarsal organ, leg I, dorsal view.

Figs. 25–30. Nyetnops guarani, new species, male. 25. Left male palp, prolateral view. 26. Same, retrolateral view. 27. Apex of embolus, prolateral view. 28. Same, retrolateral view. 29. Tip of cymbium, retrolateral view. 30. Same, detail of setae.