Trilacuna meghalaya Grismado and Piacentini, 2014

Grismado, Cristian J., Deeleman, Christa, Piacentini, Luis N., Izquierdo, Matías A. & Ramírez, Martín J., 2014, Taxonomic Review Of The Goblin Spiders Of The Genus Dysderoides Fage And Their Himalayan Relatives Of The Genera Trilacuna Tong And Li And Himalayana, New Genus (Araneae: Oonopidae), Bulletin of the American Museum of Natural History 2014 (387), pp. 1-108 : 30-40

Trilacuna meghalaya Grismado and Piacentini , new species

Figures 15–31 , 39A–B

TYPES: Male holotype and five paratype males from India: Meghalaya: Garo-Hills: above Tura , 700 m, 25.56000 ° N, 89.49000 ° E, Nov. 1, 1978, C. Besuchet, I. Löbl (MHNG PBI_OON 15401 ); 10 paratype females with same data ( MHNG PBI_OON 15404 ) .

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

DIAGNOSIS: Males of this species are similar to those of T. mahanadi by their relatively simple paraembolic projections, but the copulatory bulb has a more truncate shape in the distal part, from where the embolus and accompanying elements arise (figs. 28A–B, 31C–E, 39B), and lack stout epigastric setae. Females are easily recognized by their internal genitalia, with a medium-sized, cylindrical (sinuous in lateral view) posterior receptacle, and curved lateral projections of the anterior sclerite (figs. 22C, D, 39A).

DESCRIPTION: Male (holotype, PBI_OON 15401). Total length 1.66. Cephalothorax: Carapace sides granulate; nonmarginal pars cephalica setae light; marginal setae light, needlelike. Clypeus setae light, needlelike. Eyes ALE, PME subequal, larger than PLE, ALE circular, PLE oval; ALE–PLE separated by less than ALE radius, PME touching for less than half their length. Sternum without radial furrows between coxae I–II, II–III, III–IV, microsculpture covering entire surface, lateral margins unmodified, orange; setae sparse, but densest medially. Mouthparts: chelicerae orange; setae light. Labium with two short, laterally directed ridges. Endites orange, with a set of black, flattened, enlarged setae pointing medially (figs. 24C– D, 30 E). Abdomen: Book lung covers round. Dorsal scutum orange. Epigastric scutum not protruding. Postepigastric scutum covering about 3/4 of abdominal length, orange. Spinneret scutum absent. Dorsum setae light. Epigastric area setae uniform, light. Postepigastric area setae light. Legs: Patella plus tibia I shorter than carapace. Leg spination (all spines longer than segment width): leg I: femora: pv0-0-1-0, tibiae: v2-2-2-2-0, meta-tarsi: v2-2-0, leg II: tibiae: v2-2-2-2-0, meta-tarsi: v2-2-0. Trichobothria: tibia: each with three; metatarsus: each with one; opening longitudinally narrowed; hood covered by numerous low, closely spaced transverse ridges; basal expansion of trichobothrial setae with annular ridges (fig. 26C–G). Tarsal organ with two sensilla visible in the palp (fig. 26H), three in the leg I, one of them very small (fig. 26I). Genitalia: Epigastric region with sperm pore oval, situated at level of anterior spiracles, unmodified. Palp: distal part of the bulb with a truncate shape, with an indentation on the prolateral side, covered with setiform structures, some of them bifid (fig. 28D). Two elongated projections run parallel to the embolus at its prolateral side (fig. 28D), retrolateral surface of embolus bearing numerous spinules (fig. 28H). Two other similarly ‘‘haired’’ projection flank the embolus dorsally and retrolaterally (fig. 28E–F).

Female (paratype, PBI_OON 15404). Total length 1.78. As in male except as noted. Cephalothorax: Carapace nonmarginal pars cephalica setae in U-shaped row. PME circular. Sternum orange. Mouthparts: chelicerae orange; paturon distal region abruptly narrowed. Labium with 3–5 setae on anterior margin. Palp without spines. Abdomen: Dorsal scutum covering full length of abdomen, orange. Spinneret scutum slightly sclerotized. Legs: Femora darker than the subsequent articles. Leg spination as in male. Tarsal organ with two sensilla visible on palp and leg IV (fig. 20A, C), three on leg I, one of them very small (fig. 20B). Spinnerets (fig. 21): ALS and PMS with three spigots, PLS with five spigots. Genitalia: Copulatory opening a small slit posteriorly situated and separated from the epigastric furrow, in the middle of the transverse plates, between them lies a field of presumably glandular tissue (figs. 22E, 39A, we cannot find the external openings). The copulatory opening leads to a more or less cylindrical, medium-sized, posterior receptacle that extends anteriorly (after a short posteriorly directed part) to the vicinity of the epigastric furrow, leading to the uterus externus. The T-shaped anterior sclerite (figs. 22C, 39A), apparently without lumen, has conspicuously curved lateral bars for the attachment of muscles connecting to the lateral parts of one of the transverse plates. Transverse bars with two relatively long, lateral apodemes serve as attachment for other muscles.

OTHER MATERIAL EXAMINED: INDIA: Meghalaya: Khasi Hills: Mawphlang , 1800 m, Oct. 28, 1978, C. Besuchet, I. Löbl, 1♂ ( MACN-Ar 28839 , PBI _OON 15502) ; Khasi Hills; below Cherrapunjee , 1200 m, Oct. 26, 1978, C. Besuchet and I. Löbl, 1♀ ( MHNG PBI_OON 15392 ), 1♀ ( MACN-Ar 28838 , PBI_OON 42097 ) ; Khasi-Hills: Nongpoh , 700 m, Nov. 5, 1978, C. Besuchet and I. Löbl, 3♂ ( MHNG PBI_OON 12808 ), 1♂ ( MHNG PBI_OON 12876 ), 2♀ ( MHNG PBI_OON 15324 ), 1♂ ( MHNG PBI_OON 16158 ) ; Garo-Hills: Songsak , forest floor, bamboo litter, 400m, Nov. 02, 1978, C. Besuchet and I. Löbl, 1♀ ( MHNG PBI_OON 15411 ). Assam: Manas, Manas Wildlife Sanctuary , 200 m, 26.72500 ° N, 91.03600 ° E, Oct. 21, 1978, to Oct. 22, 1978, C. Besuchet, I. Löbl, 1♂ ( MHNG PBI_OON 15338 ).

DISTRIBUTION: Known only from Meghalaya and Assam, northeastern India.

Figures

Fig. 15. Trilacuna meghalaya, new species, female (PBI_OON 15404). A. Habitus, dorsal view. B. Same, lateral view. C. Carapace, lateral view. D. Same, dorsal view. E. Same, anterior view.

Fig. 16. Trilacuna meghalaya, new species, female (PBI_OON 15404). A. Ocular area dorsal view. B. Same, anterior view. C. Chelicerae, anterior view. D. Right cheliceral fang, anterior view. E. Chelicerae, detail of the basal processes. F. Setae with enlarged bases on the carapace, dorsal view. G. Same, lateral view.

Fig. 17. Trilacuna meghalaya, new species, female (PBI_OON 15404). A. Carapace, ventral view. B. Right palp, retrolateral view. C. Labium, ventral view. D. Right chelicerae, retromargin, showing fang and tooth. E. Right spiracles. F. Pleural area, showing pores.

Fig. 18. Trilacuna meghalaya, new species, female (PBI_OON 15404). A. Pleural and sternal area between coxae II–III, ventral view. B. Right leg I, prolateral view. C. Tibia I, dorsal view. D. Tarsus I, prolateral view. E. Right leg IV, prolateral view. F. Right tarsus IV, prolateral view.

Fig. 19. Trilacuna meghalaya, new species, female (PBI_OON 15404). A. Claws of tarsus I, dorsal view. B. Same, prolateral view. C. Claws of tarsus IV, oblique prolateral view. D. Same, detail of large teeth on claws.

Fig. 20. Trilacuna meghalaya, new species, female (PBI_OON 15404). A. Tarsal organ, palp, dorsal view. B. Same, leg I. C. Same, leg IV. D. Trichobothrial bases, tibia of palp, dorsal view. E. Same, tibia I. F. Same, metatarsus I. G. Same, metatarsus IV. H. Setae on the dorsum of abdomen.

Fig. 21. Trilacuna meghalaya, new species, female (PBI_OON 15404). Spinneret morphology. A. Spinnerets, posteroventral view. B. Detail of right anterior lateral spinneret. C. Detail of left posterior median spinneret. D. Detail of right posterior lateral spinneret.

Fig. 22. Trilacuna meghalaya, new species, female (PBI_OON 15404). Genitalic morphology. A. Epigastric region, ventral view. B. Detail of the copulatory opening. C. Internal female genital organs, dorsal view. D. Longitudinal section, lateral view (arrow = copulatory opening). E. Same, dorsal view (arrow = anterior orifice of the posterior receptacle; asterisks: transverse lateral areas with presumably glandular tissue). F. Same, detail of the anterior part of the posterior receptacle, showing the orifice of the fertilization duct, and the basal part of the anterior sclerite that locks in it.

Fig. 23. Trilacuna meghalaya, new species, male (PBI_OON 15401). A. Habitus, dorsal view. B. Same, ventral view. C. Same, anterior view. D. Carapace, dorsal view. E. Same, ventral view. F. Chelicerae, anterior view. G. Same, detail of the basal processes. H. Right cheliceral fang.

Fig. 24. Trilacuna meghalaya, new species, male (PBI_OON 15401). A–B. Ocular area (A, dorsal, B, anterior views). C. Endites and labium, ventral view. D. Left endite, detail of apical setae. E. Right cheliceral venom outlet. F. Left spiracles. G. Sternal tuft. H. Sternal pit, showing a central pore. I. Gonopore.

Fig. 25. Trilacuna meghalaya, new species, male (PBI_OON 15401). Legs. A–E. Left leg I. A. Prolateral view. B. Tarsus, prolateral view. C. Same, dorsal view. D. Tibia, retrolateral view. E. Metatarsus, retrolateral view. F. Right leg IV, retrolateral view.

Fig. 26. Trilacuna meghalaya, new species, male (PBI_OON 15401). A. Tarsal claws, leg I, oblique anterior view. B. Tarsal claws, leg IV, retrolateral view. C–G. Trichobothria. C. Palpal tibia. D. Tibia I. E. Tibia IV. F. Metatarsus I. G. Metatarsus IV. H. Tarsal organ, palp. I. Same, leg I.

Fig. 27. Trilacuna meghalaya, new species, male (PBI_OON 15401). Spinneret morphology. A. Spinnerets, posteroventral view. B. Detail of right anterior lateral spinneret. C. Detail of right posterior median spinneret. D. Detail of left posterior lateral spinneret.

Fig. 28. Trilacuna meghalaya, new species, male (PBI_OON 15401). A. Left palp, prolateral view. B. Same, retrolateral view. C. Same, dorsal view. D. Detail of the apical part of the copulatory bulb, prolateral. E. Same, retrolateral view. F. Same, dorsal view. G. Tip of embolus, prolateral view. H. Same, retrolateral view.

Fig. 29. Trilacuna meghalaya, new species, female (PBI_OON 15404). A. Habitus, dorsal view. B. Same, ventral view. C. Same, lateral view. D. Carapace, dorsal view. E. Same, ventral view. F. Same, lateral view. G. Same, anterior view. H. Epigastric area, ventral view.

Fig. 30. Trilacuna meghalaya, new species, male (PBI_OON 15401). A. Habitus dorsal view. B. Same, ventral view. C. Same, lateral view. D. Carapace, dorsal view. E. Same, ventral view. F. Same, lateral view.

Fig. 31. Trilacuna meghalaya, new species, male (PBI_OON 15401). A. Habitus, anterior view. B. Abdomen, ventral view. C. Left palp, retrolateral view. D. Same, dorsal view. E. Same, prolateral view.

Fig. 39. Trilacuna spp., genitalia. A, B. Trilacuna meghalaya, new species, A. Female (PBI_OON 15404), internal genitalia, dorsal view. AP = apodeme; AS = anterior sclerite; PR = posterior receptacle; arrow = gland field. B. Male (PBI_OON 15338), left palp, retrolateral view. C, D. Trilacuna besucheti, new species. C. Female (PBI_OON 15393), internal genitalia, dorsal view. D. Male (PBI_OON 15005), left palp, prolateral view. E, F. Trilacuna mahanadi, new species. E. Female (PBI_OON 12848), internal genitalia, dorsal view. F. Male (PBI_OON 12672), left palp, prolateral view. GT = glandular tube.