Psechrus obtectus Bayer 2012, sp. nov.
Creators: name: Bayer, Steffen
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Psechridae
Psechrus
Psechrus obtectus

description: Psechrus obtectus sp. nov.
Figs 57a–d, 58a–g, 86d, 89d, 92d
Psechrus tingpingensis — Wang and Yin 2001: 341, figs 31–47 (Description & illustration of ♂ and ♀ and SEM photos of somatic characters, misidentified).
Type material. Holotype ♂ (SB 1151), VIETNAM: Bac Thai Province: Tam Dao Mountain Forest Park (ca. 45 km NW of Hanoi), ca. N 21°27', E 105°40', 500–1000 m; X.P. Wang leg. 02.V.1999; AMNH. Paratypes: 1 ♂ (SB 1150), 4 ♀♀ (SB 1152–1155), 1 s.a. ♀ (SB 1156), same data as for holotype; AMNH.
Etymology. The specific name refers to the fact, that the distinct species status of this new species was undetected (thus concealed) for several years, due to its similarity to Psechrus tingpingensis (Latin “obtectus” means “concealed” or “hidden”); Perfect participle passive; adjective.
Diagnosis (see also diagnosis for sinensis -group above). Males similar to P. tingpingensis in general shape of embolus and tegulum and in having apically forked conductor (C). Distinguished by the two strongly sclerotised apophyses (the smaller of which more exactly an extension) at proximal half of embolus base (EB) and by the absence of apophyses at distal section of EB (Figs 57a–c). Females very similar to P. tingpingensis in shape of epigyne and general shape of vulva (see description of P. tingpingensis). Distinguished by the anterior, twisted section of copulatory duct (CD), in fact the short section beyond the transversal, initial section of CD, being shorter than half the diameter of one receptaculum (Figs 58b,g, 92d), whereas in P. tingpingensis it is almost as long as one diameter.
Description. Male (measurements of holotype first, those of paratype SB 1150 in parentheses behind):
Body and eye measurements. Carapace length 8.1 (8.5), carapace width 4.5 (6.1), anterior width of carapace 3.5 (3.6), opisthosoma length 9.4 (in paratype distal section of opisthosoma cut), opisthosoma width 4.1 (4.9). Eyes: AME 0.39 (0.42), ALE 0.46 (0.48), PME 0.49 (0.48), PLE 0.49 (0.48), AME–AME 0.22 (0.22), AME–ALE 0.04 (0.06), PME–PME 0.27 (0.26), PME–PLE 0.32 (0.37), AME–PME 0.63 (0.62), ALE–PLE 0.47 (0.46), clypeus height at AME 1.03 (1.04), clypeus height at ALE 0.93 (0.97).
Cheliceral furrow with three promarginal and five retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp: 10.7 (10.5) [3.5 (3.6), 1.9 (1.8), 1.4 (1.4), 3.9 (3.7)]; Legs: I 64.0 (69.9) [16.7 (18.2), 3.9 (4.1), 17.7 (19.5), 18.2 (20.0), 7.5 (8.1)], II 48.1 (50.2) [13.1 (13.0), 3.4 (3.5), 13.0 (13.8), 13.1 (14.2), 5.5 (5.7)], III 33.3 (34.1) [9.6 (9.8), 2.6 (2.8), 7.9 (8.2), 9.2 (9.3), 4.0 (4.0)], IV 49.6 (52.4) [13.6 (14.4), 3.1 (3.2), 12.5 (13.2), 14.3 (15.1), 6.1 (6.5)].
Spination. Palp (both specimens): 131, 110 (spines very small), 1101 (spines very small); legs: femur I 546 (654{546}), II 546 (556{546}), III 555 (545), IV 544 (545{665}); patella I–IV 000; tibia I–II 3036 (3036), III 2022 (2022), IV 3033{2031} (2030{3032}); metatarsus I–III 3035 (3035), IV 3034 (3035).
Palpal femur ventrally modified with quite strongly extended, rounded bulge (Fig. 57d). However, the extension slightly less distinct than in P. tingpingensis.
Copulatory organ (see also diagnosis and general description for sinensis -group). Embolus (E) dorsally slightly serrated (Figs 57b–c). Proximal apophysis of EB quite broad. Sperm duct with transversal section in retrolateral apical half of T and with loop in prolateral half. Palpal tibia short (Figs 57a–c).
Female:
Body and eye measurements. Carapace length 8.7–9.7, carapace width 4.2–6.6, anterior width of carapace 3.7–4.3, opisthosoma length 12.9–13.6, opisthosoma width 6.8–7.8. Eyes: AME 0.41–0.49, ALE 0.50–0.53, PME 0.48–0.54, PLE 0.49–0.53, AME–AME 0.27–0.28, AME–ALE 0.09–0.11, PME–PME 0.39–0.42, PME–PLE 0.43–0.49, AME–PME 0.66–0.74, ALE–PLE 0.61–0.69, clypeus height at AME 1.31–1.36, clypeus height at ALE 1.03–1.12.
Cheliceral furrow with three promarginal and five retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp: 10.2–11.5 [3.5–3.9, 1.5–1.8, 1.8–1.9, 3.4–3.9]; Legs: I 48.0–52.8 [12.7–14.3, 3.7–4.0, 13.4–15.4, 12.6–13.2, 5.6–5.9], II 37.3–40.2 [10.3–11.4, 3.2–3.5, 10.3–10.7, 9.2–10.0, 4.3–4.6], III 26.8–28.9 [8.0–8.3, 2.3–2.9, 6.6–6.8, 6.6–7.2, 3.3–3.7], IV 38.2–41.7 [10.5–12.0, 2.9–3.4, 10.1–10.7, 10.0–10.5, 4.7–5.1].
Palpal claw with 15–16 teeth.
Spination. Palp: 131, 110, 1101, 1014; legs: femur I 546, II 545 (556,545), III 545 (555), IV 554; patella I–IV 000; tibia I– II 3036, III 2022 (2032), IV 2023 (2032); metatarsus I– III 3035, IV 3034.
Copulatory organ (see also diagnosis and general description of sinensis -group). Epigynal field (EF) may be associated with epigynal muscle sigilla (EM) (Fig. 58f). The latter mostly slightly broader than in P. tingpingensis. Slit sense organs (SO) outside EF (Fig. 58a, 58f). Initial section of CD (Figs 58b,g) mostly slightly narrower than in P. tingpingensis, mesal section mostly slightly broader. Spermathecal heads like in P. tingpingensis.
Primordial copulatory organ. Pre-epigyne: Pre-septum about as long as broad and posteriorly broader than anteriorly (Fig. 58d). With small, slightly curved transversal edges in front of pre-CO.
Pre-vulva: Pre-CD longer than pre-receptacula (Fig. 58e) and narrower than in P. senoculatus.
Colouration of male and female (see also description for sinensis -group and Psechrus). Median bands on carapace slightly serrated. Lateral bands absent or very narrow (at most 0.2 diameter of PME) and not serrated. Light longitudinal line ventrally on opisthosoma broken subdistally or strongly constricted subdistally and broad. If measured centrally on opisthosoma, its width is 0.7–0.9 of one half of the cribellum. Distal part (patch) broader than main section.
Distribution. Vietnam (Fig. 96).
description: Published as part of Bayer, Steffen, 2012, The lace-sheet-weavers — a long story (Araneae: Psechridae: Psechrus), pp. 1-170 in Zootaxa 3379 (1) on pages 105-108, DOI: 10.11646/zootaxa.3379.1.1, http://zenodo.org/record/6039832