Psechrus insulanus, sp. nov.
Creators: name: Bayer, Steffen
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Psechridae
Psechrus
Psechrus insulanus

description: Psechrus insulanus sp. nov.
Figs 11, 25 D, 26D, 34
Type material. Holotype ♂ (SB 1247): THAILAND: Phang Nga Prov.: Khuraburi Distr., Ko Surin Nuea (means northern Surin island), behind Ao Chong Khad, 10–30 m, 09°25'25''N, 97°52'10''E, evergreen forest, P. Schwendinger leg. 17.– 18.XII.2012, sample number: TH-12/01, MHNG.
Etymology. The specific name refers to the type locality, a small island close to the west coast of Southern Thailand (Latin “ insulanus ” means ‘inhabiting an island’); adjective.
Diagnosis (consider also the diagnosis for the himalayanus -group above): Males distinguished from those of all other species of the himalayanus -group, except P. jaegeri and P. vivax Bayer, 2012, by the combination of the following characters: cymbial scopula absent (Fig. 26 D); palpal tibia less than 1.4 times longer than broad; embolus curved, basally with ridges. Distinguished from the similar P. jaegeri and P. vivax by the following characters: Embolus shorter, and less curved (Figs 11 B–C); retrolateral section of distal, narrower part of tegulum still visible in ventral view (see arrow in Fig. 11 B), not so in P. jaegeri and P. vi v ax; proximal section of sperm duct with slightly different course (Figs 11 B, 25D), palpal tibia shorter than in P. jaegeri and P. vivax, hardly longer than broad (Figs 11 A,C, 26D).
Description. Male: Body and eye measurements: Carapace length 8.5, maximal carapace width 6.4, anterior width of carapace 3.1, opisthosoma length 12.1, opisthosoma width 4.3. Eyes: AME 0.42, ALE 0.49, PME 0.51, PLE 0.47, AME–AME 0.32, AME–ALE 0.07, PME–PME 0.29, PME–PLE 0.38, AME–PME 0.83, ALE–PLE 0.61, clypeus height at AME 1.09, clypeus height at ALE 0.96.
Cheliceral furrow with three promarginal (four at right chelicera) and four retromarginal teeth.
Spination: Palp: 131, 110 (prolateral one less than half as long as dorsal one), 1101 (all spines less than half as long and broad as those on femur); legs: femur I 656{556}, II 566{556}, III–IV 555; patella I–IV 000; tibia I–II 3038, III 3134 (dorsal spine less than half as long and broad as others), IV 3136; metatarsus I–III 3035, IV 3034.
Measurements of palp and legs: Palp 9.8 [3.5, 1.7, 1.4, 3.2], I 75.5 [20.6, 4.3, 20.8, 21.1, 8.7], II 58.0 [16.1, 3.8, 15.2, 16.5, 6.4], III 40.7 [12.0, 2.9, 10.1, 10.9, 4.8], IV 60.9 [16.8, 3.4, 15.8, 17.4, 7.5]. Leg formula: 1423. FEMI+MTT-I/CL=4.91, thus, legs within the general range of males of the himalayanus -group (on average ca. 5).
Palpal femur without modification and straight (Fig. 11 D). Macrosetae ventrally on coxae of leg I, which are typical for males of the himalayanus -group, present in male SB 1247, but clearly less developed than in other species like P. vivax or P. himalayanus Simon, 1906.
Copulatory organ (see also diagnosis above and general description for himalayanus -group in Bayer 2012): Cymbium distally narrow (Figs 11 A–C) and without dorsal scopula (Fig. 26 D); tegulum ca. 1.7 times longer than broad (Fig. 11 B, 25D); conductor with very fine, transparent and sail-shaped distal flange (Fig. 11 B) and arising in a 11:30 o’clock position on tegulum; tubercles (tiny teeth) prolatero-ventrally on embolus hardly visible and thus finer than in P. j aegeri and P. vivax; transversal section of sperm duct with slight curve centrally; subtegulum in ventral view only slightly protruding from underneath tegulum (Fig. 11 B), but visible in prolateral view (Fig. 11 A).
Colouration (see also description for himalayanus -group and Psechrus in Bayer 2012). Median bands on carapace serrated, lateral bands also serrated and if compared with other species of the himalayanus -group relatively narrow (broadest section ca. 1.2 diameter of PME). Light longitudinal line ventrally on opisthosoma continuous and narrow. If measured centrally on opisthosoma, its width is less than the width of one half of the cribellum (ca. 0.3–0.4 of one half of the cribellum).
Female: unknown.
Distribution. Thailand (Fig. 34).
description: Published as part of Bayer, Steffen, 2014, Seven new species of Psechrus and additional taxonomic contributions to the knowledge of the spider family Psechridae (Araneae), pp. 1-54 in Zootaxa 3826 (1) on page 21, DOI: 10.11646/zootaxa.3826.1.1, http://zenodo.org/record/286429