Trilacuna clarissa Eichenberger

Eichenberger, Beata & Kranz-Baltensperger, Yvonne, 2011, New Trilacuna species from Thailand, Malaysia and Sumatra (Araneae, Oonopidae), Zootaxa 2823, pp. 1-31 : 10

Trilacuna clarissa Eichenberger n. sp.

( Figs. 7–9 )

Type material: Holotype male ( PBI_OON 00012418 ): Sumatra: West Sumatra Province: Rimbo Panti Nature Reserve, about 30 km N of Lubuksikaping , 0°20'46"N, 100°04'09"E, 300–400 m, primary forest, 11/13 June 2006, leg. P. Schwendinger, deposited in MHNG. 1 male paratype ( PBI_OON 00031971 ), collected with holotype, deposited in MHNG. 1 male paratype (PBI_OON 00031972), collected with holotype, deposited in MHNG. 1 male paratype ( PBI_OON 00031973 ), collected with holotype, deposited in NMBE.

Etymology: The species epithet refers to the name of Agatha Christie, born as Agatha Mary Clarissa Miller, who was a brilliant and famous English author of novels, short stories and plays.

Diagnosis: This species can be distinguished from all other Trilacuna species by the sternum surface with relatively small, ovoid pits (figs. 7. D, F, H) and abundant, evenly scattered, plumose setae (fig. 7. H).

Description: Description based on 4 males (plus 2 males for SEM).

MALE: Body length 1.1 mm, proportion carapace length:abdominal length 1:1. Uniformly orange-brown species (figs. 7. A–C).

Carapace broadly oval, strongly elevated, surface smooth, without spikes, lateral margin straight, with blunt denticles, with second, strongly rebordered, straight margin below (figs. 7. E, G; 8. B). Eyes posterior row straight from above, procurved from front (figs. 7. E; 8. B). Sternum with radial furrows of small pits between coxae, anterior margin with transverse groove. Mouthparts: Chelicerae promargin with row of flattened hairs (fsh) in combination with feather-like hairs (flh), (see fig. 2. E); labium triangular, not fused to sternum, anterior margin deeply incised (ldi), (figs. 8. C–D); endites slender, distally only slightly branched, with distal patch of fork-like serrated setae (coh), outer part with some broadish, funnel shaped, distally serrated setae (fuh), (fig. 8. E).

Abdomen: Broadly-ovoid, dorsal scutum not fused to epigastric scutum, postepigastric scutum short, almost circular, with short, posteriorly directed lateral apodemes, posterior spiracles not connected by groove or dark belt (fig. 8. H), booklung covers roundish.

Legs: Ventral apex of tibiae III and IV with one or few specialized hairs with fine, plumose, curved hair tip (see fig. 16. H); metatarsi III, IV and tarsus IV with harpoon-like hairs (see fig. 2. G); tibiae I and II ventral surface with smooth stripes containing pores (figs. 8. F–G), less distinct stripes also observed on femora I–IV and metatarsi III– IV, pores not observed but absence unproved. Femora without spines.

Male genitalia: Male palp (figs. 9. A–I) embolus (emb) light, short and straight; retrolateral-dorsally framed by a brush of thickened hairs (bsh) (figs. 9. E–I); conductor-complex about as long as embolus, divided in a prolateral, broadish branch (pbb) and in a ventral branch (vb), both surrounded by numerous setae (figs. 9. E–I). Bulb about twice as long as cymbium, stout, tapering apically (figs. 9. A–C). Femur elongated, slender (figs. 9. A–B).

FEMALE: unknown.

Distribution: Known only from the type locality, the Rimbo Panti Nature Reserve on Sumatra.

Figures

FIGURE 7: Trilacuna clarissa n. sp. Male: A. habitus dorsal view; B. habitus ventral view; C. habitus lateral view; D. sternum ventral view; E. carapace dorsal view; F. sternum ventral view, SEM; G. carapace dorsal view, SEM; H. sternum surface ventral view, SEM. Abbreviations: boc, booklung covers. Scale bars: A – G 0.5 mm; H 100 Μm.

FIGURE 8: Trilacuna clarissa n. sp. Male: A. carapace anterior view; B. carapace anterior view, SEM; C. endites ventral view; D. endites ventral view, SEM; E. right endite, ventral view, distal inner margin; F. tibia I prolateral view, SEM; G. tibia I prolateral view, smooth stripe with pore; H. gonopore ventral view. Abbreviations: ehb, elevated hair base; ldi, labium deep incision; coh, comb-like hairs; fuh, funnel-shaped hairs. Scale bars: A 0.5 mm; B 300 Μm; C – D, H 200 Μm; E 20 Μm; F 100 Μm; G 10 Μm.

FIGURE 9: Trilacuna clarissa n. sp. Male: A – B. left palp, prolateral view; C. right palp, prolateral view, SEM; D. right palp, dorsal view, SEM; E. left embolus, prolateral view; F. left embolus, prolateral view, SEM; G. right embolus, dorsal view, SEM; H. left embolus, dorsal view, SEM; I. left embolus, dorsal view, distal tip, SEM. Abbreviations: emb, embolus; bsh, brush of thickened hairs; pbb, prolateral broadish branch; vb, ventral branch. Scale bars: A – D 100 Μm; E – H 20 Μm; I 10 Μm.