Xyphinus acutus Kranz-Baltensperger 2014, sp. nov.
Creators: name: Kranz-Baltensperger, Yvonne
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Oonopidae
Xyphinus
Xyphinus acutus

description: Xyphinus acutus sp. nov.
(Figs 33–36; map 3)
Type material. Holotype: male (PBI _ OON 00032568) from MALAYSIA: Sabah, Danum Valley, primary forest, 7.–16.V.1991, leg. C.L. and P. R. Deeleman, RMNH. Paratypes: 5 male & 7 female (PBI _ OON 00031955), collected with holotype, RMNH. 1 female (PBI _ OON 00035445), Orchid Trail, N 4°57'47", E 117°48'10", 525 m, 1 maxi winkler, 19.VIII.2010, leg. Brian L. Fisher, BLF25145, California Academy of Sciences, CASENT 9039825, CAS. 7 males & 3 females (PBI _ OON 00031958), leg. Deeleman, RMNH. INDONESIA: 4 males (PBI _ OON 00031698), East Kalimantan Prov., Berau Distr., 1 km off road Tanjungredeb to Tanjungselor, ca. 45 km N of Tanjungredeb, N 2°29'33", E 117°28'46", 190 m, primary forest, 29.IX./ 3.X.2008, leg. P. Schwendinger, MHNG.
Etymology: The specific name is a Latin adjective meaning “pointed” and refers to the conspicuous structure in the female epigastric area.
Diagnosis. With its strongly projecting abdomen X. acutus sp. nov. is similar to X. gibber, X. montanus and X. deelemanae sp. nov., but can be distinguished by the combination of the following traits: presence of microsculpture on the male palpal patella and tibia (Fig. 34A, C, F, G) as well as on the promarginal surface of the male chelicerae (Fig. 33G, H) and the broad and slightly elongated apophysis on the palpal bulb (Fig. 34). The female can be separated from all other Xyphinus females by the elongated, pointed scape in the epigastric area (Figs 35B, C, E; 36).
Description. Male. Total length 1.93 mm. Carapace: Orange-brown, broadly oval in dorsal view, domed in lateral view, anteriorly narrowed to 0.49 times its maximum width or less, with angular posterolateral corners, posterolateral edge without pits, anterolateral corners without extensions or projections, posterolateral surface without spikes (Fig. 33A, C, D), surface of pars cephalica smooth, sides slightly reticulate, fovea present. Lateral margin with blunt denticles. Clypeus: Sinuous in frontal view, sloping forward in lateral view, high, ALE separated from edge of carapace by their radius or more (Fig. 33D). Eyes: PME largest, ALE and PLE circular, PME oval. Posterior eye row recurved from above, procurved from front. ALE separated by their radius to diameter, ALE and PLE touching, PLE and PME separated by less than PME radius, PME touching (Fig. 33A, D). Sternum: as long as wide, sickle-shaped structures not touching. Radial furrows opposite coxae III absent. Surface smooth (Fig. 33B, F). Mouthparts: Chelicerae widely divergent, anterior face unmodified, promargin with microsculpture (Fig. 33D, G, H). Labium hexagonal, indented at middle, with 3-5 setae on anterior margin. Abdomen: Frontally strongly narrowed, overlapping carapace, almost reaching highest point of carapace (Fig. 33C). Book-lung covers elliptical. Scuto-pedicel region with few sharply pointed denticles with elongated setae (Fig. 33E). Dorsal scutum orange brown, middle surface and sides punctate, anterior half without projecting denticles. Dorsal scutum embedding narrow tip of abdomen (Fig. 33C, E). Epigastric scutum not protruding. Postepigastric scutum with short posteriorly directed lateral apodemes. Posterior spiracles connected by groove. Legs: Metatarsi of legs III and IV with harpoon-like hairs. Tibia with three, metatarsi with one trichobothria each. Genitalia: Sperm pore small, situated at level of anterior spiracles. Trochanter normal size, unmodified. Femur two or more times as long as trochanter, attaching to patella basally; patella shorter than femur, with microsculpture on prolateral surface, tibia two times as long as patella, with microsculpture on prolateral side, with three trichobothria (Fig. 34A, C, F). Cymbium pale yellow, ovoid in dorsal view, not fused with bulb, bulb almost black, 1 to 1.5 times as long as cymbium, middle and distal part strongly sclerotized. Thick, sclerotized outgrowth prolaterally, elongated, broad apophysis retrolaterally, slightly curved at its tip, small, membranous apophysis dorsally (Fig. 34).
Female. Total length 2.08 mm. Carapace: Pars cephalica slightly elevated in lateral view. Mouthparts: Chelicerae slightly divergent, unmodified (Fig. 35D). Female palp spineless, femora with two strong, spine-like hairs ventrally, tibia with three trichobothria and few stronger setae prolaterally (Fig. 35F). Abdomen: Epigastric scutum strongly protruding (Fig. 35C). Genitalia: Epigastric furrow narrow. Two transverse sclerites visible between pedicel and epigastric furrow (Fig. 35E). Postepigastric scutum with sclerotized, scape-like structure, elongated posteriorly, reaching the middle of the ventral scutum, ending acute (Figs 35B, E; 36).
description: Published as part of Kranz-Baltensperger, Yvonne, 2014, The goblin spider genus Xyphinus (Araneae; Oonopidae), pp. 1-79 in Zootaxa 3870 (1) on pages 41-45, DOI: 10.11646/zootaxa.3870.1.1, http://zenodo.org/record/4947426