Psechrus khammouan Jager 2007
Creators: name: Bayer, Steffen
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Psechridae
Psechrus
Psechrus khammouan

description: Psechrus khammouan Jäger, 2007
Figs 28a–d, 29a–e, 82b, 85e, 88e, 91e
Psechrus khammouan Jäger 2007: 47, figs 54–67 (Description of ♂ and ♀, illustration of ♂ and ♀). [Holotype ♂ (SB 1038) from LAOS: Khammouan Province: Thakek, 9.5 km NE Thakek, N 17°26'56.2'', E 104°52'30'', 160 m, cave entrance, rock wall; P. Jäger & V. Vedel leg. 30.X.2004; SMF 56386; Paratypes: 1 ♀ (SB 1039) from Khammouan Province: Ban Thathot, N 17°37'54'', E 105°07'30'', 200 m, cave entrance of Tham Kamouk Limestone Cave; P. Jäger leg. 19.II.2003; SMF 56387; 1 ♀ (SB 1040) from same locality as SB 1039, but: primary forest between street and cave; P. Jäger leg. 19.II.2003; SMF 56388; all type material examined]. Bayer and Jäger 2010: 59.
Additional material examined (1 ♂, 4 ♀♀). LAOS: Khammouan Province: Thakek, 9.5 km NE Thakek, N 17°26'56.2'', E 104°52'30'', 160 m, cave entrance area, rock wall; P. Jäger & S. Bayer leg. 06.XI.2009; 1 ♂ (SB381), 1 ♀ (SB 382), SMF. Ban Kouanphavang, N 17°27'09'', E 104°56'19'', ca. 180 m, in/ near cave; P. Jäger & S. Bayer leg. 06.XI.2009; 1 ♀ (SB 379) (in cave), 1 ♀ (SB 380) (outside cave, between rocks), SMF. Ban Thathot, N 17°37'54'', E 105°07'30'', 200 m, cave entrance of Tham Kamouk Limestone Cave; P. Jäger & F. Steinmetz leg. 10. III.2007; 1 ♀ (SB 63), SMF.
Revised diagnosis (see also diagnosis for ancoralis -group above). Males similar to P. antraeus in having distally curved embolus (E) and long and narrow conductor (C). Distinguished by the shorter E and C (Figs 28a–c) and the bulky T (Fig. 28c). Females similar to P. steineri Bayer & Jäger, 2010 in having median septum (MS) with diverging lateral margins (Figs 29a,e, 30e), initial sections of copulatory ducts (CD) running transversally and spermathecal heads, which are clearly separated from spermathecae (at least 2x the diameter of one SH) (Figs 29b,d, 30f). Distinguished by the less diverging MS-margins (Figs 29a,e) and the distinctly longer CD (Figs 29b,d).
Description. Male (only holotype, measurements of other male not, or just insignificantly deviating):
Body and eye measurements. Carapace length 5.1, carapace width 3.7, anterior width of carapace 2.0, opisthosoma length 7.5, opisthosoma width 2.8. Eyes: AME 0.30, ALE 0.35, PME 0.36, PLE 0.35, AME–AME 0.14, AME–ALE 0.03, PME–PME 0.22, PME–PLE 0.28, AME–PME 0.44, ALE–PLE 0.32, clypeus height at AME 0.64, clypeus height at ALE 0.58.
Cheliceral furrow with three promarginal and five retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp: 6.6 [2.3, 1.1, 1.2, 2.0]; Legs: I 51.0 [13.5, 2.5, 14.5, 14.8, 5.7], II 38.0 [10.2, 2.2, 10.3, 10.9, 4.4], III 24.5 [7.0, 1.7, 6.0, 6.8, 3.0], IV 38.7 [10.4, 1.9, 9.9, 11.5, 5.0].
Spination. Palp: 131, 110 (prolateral one very small), 1101 (prolateral and ventral one very small); legs: femur I 667, II 566, III–IV 555; patella I–IV 000; tibia I–II 3038, III 3136, IV 3135; metatarsus I–IV 3035.
Palpal femur long and slim, without modification (Fig. 28d).
Copulatory organ (see also diagnosis and general description for ancoralis -group). Conductor (C) distally folded ventrad (Figs 28b,c). Palpal tibia (Figs 28a–c) quite long.
Female:
Body and eye measurements. Carapace length 5.5–7.8, carapace width 3.7–5.4, anterior width of carapace 2.4–3.4, opisthosoma length 7.8–9.1, opisthosoma width 3.4–4.5. Eyes: AME 0.33–0.46, ALE 0.38–0.48, PME 0.39–0.49, PLE 0.38–0.49, AME–AME 0.18–0.22, AME–ALE 0.05–0.07, PME–PME 0.23–0.27, PME–PLE 0.36–0.40, AME–PME 0.59–0.63, ALE–PLE 0.36–0.45, clypeus height at AME 0.71–1.12, clypeus height at ALE 0.65–1.08.
Cheliceral furrow with three promarginal and five (proximal of which smaller) retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp: 7.5–9.4 [2.6–3.2, 1.0–1.3, 1.4–1.9, 2.5–3.0]; Legs: I 40.2–46.4 [11.2–12.4, 2.4–3.2, 11.7–13.5, 10.3–12.0, 4.6–5.3], II 31.3–36.9 [8.8–10.3, 2.1–3.0, 8.7–10.2, 8.0–9.3, 3.7–4.1], III 21.3–26.3 [6.3–8.0, 1.7–2.2, 5.3–6.7, 5.5–6.5, 2.5–2.9], IV 32.2–38.5 [9.4–11.1, 1.9–2.6, 8.6–10.1, 8.3–10.1, 4.0–4.6].
Palpal claw with 13–14 teeth.
Spination. Palp: 131, 110, 1101, 1014; legs (—except for patella— variable, only most common states noted): femur I 555 (556,566), II 555 (566), III 555 (556), IV 555 (554); patella I–IV 000; tibia I–II 3038, III 3134 (3035), IV 3136 (3033,3133); metatarsus I–III 3035, IV 3034 (3035).
Copulatory organ (see also diagnosis and general description of ancoralis -group). Epigynal muscle sigilla and slit sense organs outside epigynal field (Figs 29a,e). Spermathecal heads located anterio-medially (Figs 29b,d), at distinct bend of CD.
Colouration of male and female (see also description for ancoralis -group and Psechrus). Median bands on carapace not serrated (Fig. 82b). Lateral bands extremely narrow or not even recognisable (at most 1/4 diameter of PME), not serrated (Fig. 82b). Light longitudinal line ventrally on opisthosoma continuous and narrow. If measured centrally on opisthosoma, its width ca. 1/3 the width of one half of the cribellum.
Variation of copulatory organs. The two males examined show no significant variation. In females there are differences in shape of MS (Figs 29a,e, 88e), which are not linked to geographical location. Further, there are differences in the shape of vulva. Spermathecae are slightly larger in some specimens (Fig. 29d). Spermathecal head position seems shifted posteriorly on copulatory duct (CD) in two of the three specimens from Thakek region (Fig. 29d). In the specimens from Ban Thathot the initial part of CD does not exactly run transversally, but slightly from anterio-lateral to posterio-medial (Fig. 29b). In the females from Thakek region it runs either transversally or slightly from posterio-lateral to anterio-medial (Figs 29d, 91e). In specimens from Thakek region the entire vulva half is shifted somewhat ventrally, which gives the impression that the CD was shorter (Figs 29d, 91e).
With few specimens available it presently cannot be clarified if the differences between the specimens from Ban Thathot region and Thakek region are species-specific or if they fall in the variation spectrum of P. khammouan. As long as there are no further specimens from Ban Thathot region available, especially no males, I consider the respective females (including the paratypes) belonging to P. khammouan.
Distribution. Laos (Fig. 98).
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 59-62, DOI: 10.11646/zootaxa.3379.1.1, http://zenodo.org/record/6039832