Ischnothyreus tioman, sp. nov.
Creators: name: Kranz-Baltensperger, Yvonne
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Oonopidae
Ischnothyreus
Ischnothyreus tioman

description: Ischnothyreus tioman sp. nov.
(Figs 1–2, 7)
Type material. Holotype: male (PBI_OON 00016226), MALAYSIA, Tioman Island (= Pulau Tioman), westside, 2 km SE of Kampung Genting, 100m, 2°47’N, 104°8’E, 27.VI.2001, leg. A. Schulz & K. Vock, MHNG. Paratypes: 1 male (PBI_OON 00032396), collected with holotype, MHNG. 1 male & 1 female (PBI_OON 00012048), Tioman Island, near Kampung Genting, 100–250m, 2°46’N, 104°08’E, 20.VIII.2004, leg. A. Schulz, MHNG. 1 male & 1 female (PBI_OON 00015416), Tioman Island, near Kampung Genting, 50m, 2°47’0”N, 104°08’4”E, 24.IV.2005, leg. A. Schulz, MHNG. 1 male (PBI_OON 00016170), Tioman Island, westside of Mount Kajang (= Gunung Kajang), 2 km E of Kampung Genting, 400m, 2°47’N, 104°8’E, 2.VII.2001, leg. A. Schulz & K. Vock, MHNG. 1 female (PBI_OON 00016160), same data as holotype, but 25.VI.2001, MHNG. 1 male (PBI_OON 00032350), same data as holotype, MHNG. 1 male (PBI_OON 00015674), same data as holotype, but 28.VI.2001, MHNG.
Etymology. The specific name is a noun in apposition and refers to Tioman Island, where this species was collected.
Diagnosis. The male of I. tioman can be easily recognized by the long, frontal apophyses on the chelicerae and the enormous anvil-shaped outgrowth of the palpal bulb (Fig. 1 C–F). The female genital area is characterized by the short winding tube and the heavily sclerotized lateral apodemes (Fig. 2 C–E).
Description. Male. Total length 1.32 mm. Carapace: pale orange, with dark brown egg-shaped patches behind eyes, ovoid in dorsal view, strongly elevated in lateral view, surface of elevated portion of pars cephalica smooth, sides finely reticulate, fovea absent, lateral margin straight, smooth. Clypeus: straight in frontal view, vertical in lateral view, high, ALE separated from edge of carapace by their radius or more. Eyes: six, well developed, ALE largest, ALE circular, PME and PLE oval, posterior eye row procurved from both above and front, ALE touching, ALE-PLE touching, PME touching, PLE-PME touching. Sternum: longer than wide, pale orange, uniform, not fused to carapace, surface smooth, setae abundant. Mouthparts: Chelicerae, endites and labium pale orange. Chelicerae straight, with sclerotized, spine-like apophyses (sla) on the anterior face of the paturon, about as long as paturon, originating near base (Fig. 1 C–D). Anterior face without prominent basal process and with three trichobothria-like setae (arrows) (Fig. 1 D); fang groove with few small denticles. Labium rectangular, fused to sternum, anterior margin not indented at middle. Anteromedian tip of endites with one strong, tooth-like projection (stp) (Fig. 1 B). Abdomen: ovoid, rounded posteriorly. Posterior spiracles not connected by groove. Pedicel tube short, unmodified, scutum not extending far dorsal of pedicel. Dorsal scutum weakly sclerotized, pale orange, covering about 1/2 of abdomen, between 1/4 and 1/2 abdomen width, fused to epigastric scutum, middle surface and sides smooth. Epigastric and postepigastric scutum weakly sclerotized, pale orange, fused, without posteriorly directed lateral apodemes. Dorsum setae present, light, needle-like. Legs: pale orange, leg spines longer than segment width, spine formula: femora: I p0-0-2; r0-0-1; II p0-0-1; tibiae: I, II p2-1-1; r2-1-1; metatarsi: I, II p1-1-0; r1-1-0. Trichobothria not examined. Genitalia: Epigastric region with sperm pore small, circular, situated at level of anterior spiracles, anterior margin of sperm pore with a fringe of needle-like setae. Palp normal size, strongly sclerotized, right and left palps symmetrical, proximal segments brown, trochanter normal size, with ventral projection (vp), femur normal size, one to two times as long as trochanter, attaching to patella basally, patella about as long as femur, not enlarged, tibia with three trichobothria, cymbium brown, fused with bulb, bulb brown, more than 2 times as long as cymbium, stout, tapering apically, with ventral protuberance (vpr) and anvil-shaped outgrowth (aso) dorsally, distal part with lobe (l) and pointed incision (pi), embolus (e) short, thin (Fig. 1 E–F).
Female. Total length 1.46 mm. As in male except as noted. Carapace: without any pattern, broadly oval in dorsal view, low, ALE separated from edge of carapace by less than their radius. Sternum with setae sparse. Labium with 1 or 2 setae on anterior margin. Endites unmodified. Femur of palp with three spines, tibia with three trichobothria. Abdomen: Dorsal scutum covering less than 1/2 of abdomen, not fused to epigastric scutum. Epigastric scutum small, lateral sclerites present. Postepigastric scutum widely hexagonal, only around epigastric furrow, not fused to epigastric scutum. Legs: spine formula: femora: I p0-0-2; r0-0-2; II p0-0-1; r0-0-1; tibiae: I, II p2-1-1; r2- 1-1; metatarsi: I, II p1-1-0; r1-1-0. Genitalia: The posterior margin of the epigastric scutum is lined with numerous needle-like setae. In the middle of the margin of the postepigastric scutum starts a short winding tube running posteriorly (wt) (Fig. 2 D–E). Lateral apodemes thick and strongly sclerotized (a) (Fig. 2 C–E).
Distribution. Tioman Island.
description: Published as part of Kranz-Baltensperger, Yvonne, 2012, Three new species of the oonopid spider genus Ischnothyreus (Araneae: Oonopidae) from Tioman Island (Malaysia), pp. 37-47 in Zootaxa 3161 (1) on pages 38-39, DOI: 10.11646/zootaxa.3161.1.3, http://zenodo.org/record/214142