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

description: Psechrus jaegeri sp. nov.
Figs 48a–d, 49a–g, 50f, 81g, 83c, 85n, 88n, 91n
Type material: Holotype ♀ (SB 530), LAOS: Champasak Province: Muang Bachieng, Ban Lak 38, That Fane, N 15°11'03.0'', E 106°07'36.9'', 952 m, very small, narrow valley in marginal primary forest, rock with moss; P. Jäger leg. 14.III.2010; SMF. Paratypes (1 ♂, 6 ♀♀, 3 s.a. ♀♀): 1 ♂ (SB 302), 5 ♀♀ (SB 531, 534, 536, 539, 905), same data as for holotype, except collectors: P. Jäger leg. 13.–17.III.2010 (all females), P. Jäger & S. Bayer leg. 27.XI.2009 (male); SMF; 1 ♀ (SB 300), 2 s.a. ♀♀ (SB 301, 405), LAOS: Champasak Province: Muang Bachieng, Ban Lak 35, That Itou, N 15°11'37.7'', E 106°06'06.3'', 810 m, secondary forest, close to small river, in tree holes and between tree roots [SB 300 in tube underneath road]; P. Jäger & S. Bayer leg. 26.XI.2009; SMF; 1 s.a. ♀ (SB 304), LAOS: Champasak Province: Muang Bachieng, That Paxuam, N 15°10'35.5'', E 105°55'21.0'', 197 m, secondary forest, in tree holes and between tree roots; P. Jäger & S. Bayer leg. 25.XI.2009; SMF.
Additional material examined (1 s.a. ♂, 2 s.a. ♀♀, 1 p. s.a. ♂, 1 p. s.a. ♀, 4 juvs). LAOS: Champasak Province: Muang Bachieng, That Paxuam, N 15°10'35.5'', E 105°55'21.0'', 197 m, secondary forest, in tree holes and between tree roots; P. Jäger & S. Bayer leg. 25.XI.2009; 1 s.a. ♀ (SB 307), 1 p. s.a. ♀ (SB 347), 1 s.a. ♂ (SB 306), 1 p. s.a. ♂ (SB 399), 1 juv. (SB 309), SMF. LAOS: Champasak Province: Muang Pathoumphone, Ban Tha Hou, N 14°46'09.6'', E 105°59'34.5'', 132 m, rock wall; P. Jäger & S. Bayer leg. 22.XI.2009; 3 juvs (SB 311–312, 348), SMF.
Doubtful material examined: THAILAND: Kanchanaburi Province: Si Sawat, Erawan National Park, Cave Phra Dath; C.L. & P.R. Deeleman leg. 13. III.1986; 1 ♀ (SB 121), Deeleman Coll. in RMNH.
Etymology. The specific name is a patronym in honour of the collector of the type material, Peter Jäger, who I admire for his great knowledge and special skills in arachnology; noun (name) in genitive case.
Diagnosis (see also diagnosis for himalayanus -group above). Males similar to P. vivax sp. nov. in having strongly curved embolus (E) with several ridges and an almost square course of sperm duct (Figs 48a–c, 50a–c). Distinguished by the narrower, distinctly curved distal section of E and the flat lobe ventrally at its subdistal part (Fig. 50f). Moreover, in the tegulum (T) the distal half is narrower than the basal half (Fig. 48b). Females similar to P. vivax sp. nov. in having mushroom-like shape of median septum (MS) (Fig. 49a, 51a,f), very short copulatory ducts (CD) and compact spermathecae with their heads (SH) on top (Fig. 49b, 51b,g). Distinguished by the broader anterior part of MS (ratio anterior part / posterior part> 2.6) (Fig. 49a) and the even more compact spermatheca (Fig. 49b).
Description. Male:
Body and eye measurements. Carapace length 6.4, carapace width 4.7, anterior width of carapace 2.6, opisthosoma length 9.1, opisthosoma width 3.4. Eyes: AME 0.36, ALE 0.43, PME 0.43, PLE 0.42, AME–AME 0.16, AME–ALE 0.06, PME–PME 0.24, PME–PLE 0.33, AME–PME 0.55, ALE–PLE 0.40, clypeus height at AME 0.73, clypeus height at ALE 0.66.
Cheliceral furrow with three promarginal and four retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp: 8.1 [2.9, 1.4, 1.1, 2.7]; Legs: I 57.0 [15.2, 3.1, 15.7, 16.1, 6.9], II 43.9 [12.9, 2.8, 12.2, 11.5, 4.5], III 30.6 [8.8, 1.9, 7.7, 8.2, 4.0], IV 47.3 [12.7, 2.6, 12.4, 13.5, 6.1].
Spination. Palp: 131, 010, 0100; legs: femur I–III 566, IV 555; patella I–IV 000; tibia I–II 3038, III 3035, IV 3035{3036}; metatarsus I–II, IV 3035, III 3034.
Palpal femur without modification (Fig. 48d).
Copulatory organ (see also diagnosis and general description for himalayanus -group). Conductor (C) narrow, distal section slightly broader (Fig. 48b). Palpal tibia in lateral view short (Fig. 48a,c). Cymbium dorsally without scopula (Fig. 83c).
Female (Measurements of holotype first, those of paratype females as range in parentheses):
Body and eye measurements. Carapace length 8.5 (7.0–8.4), carapace width 5.6 (3.3–5.8), anterior width of carapace 3.2 (2.1–3.5), opisthosoma length 10.2 (6.6–10.4), opisthosoma width 5.2 (3.6–5.8). Eyes (only those of holotype listed, no significant size variation in paratype females): AME 0.39, ALE 0.50, PME 0.53, PLE 0.49, AME–AME 0.24, AME–ALE 0.06, PME–PME 0.28, PME–PLE 0.43, AME–PME 0.65, ALE–PLE 0.50, clypeus height at AME 0.97, clypeus height at ALE 0.86.
Cheliceral furrow with three promarginal and four retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp: 9.7 (8.8–9.9) [3.3 (3.0–3.3), 1.4 (1.3–1.5, 1.8 (1.7–1.9), 3.2 (2.8–3.2)]; Legs: I 47.8 (42.2–49.3) [12.8 (11.4–13.1), 3.7 (3.1–3.9), 13.0 (11.3–13.2), 12.5 (11.2–13.1), 5.8 (5.2–6.0)], II 38.5 (34.7–38.6) [10.7 (9.8–10.9), 3.2 (2.7–3.4), 10.0 (9.2–10.1), 9.9 (8.9–10.3), 4.7 (4.1–4.9)], III 28.0 (24.7–28.8) [8.3 (7.2–8.3), 2.5 (2.1–2.5), 6.7 (6.0–6.9), 7.0 (6.3–7.5), 3.5 (3.1–3.6)], IV 40.4 (36.0–41.7) [11.5 (10.1–11.5), 2.8 (2.5–3.1), 10.1 (9.1–10.5), 10.8 (9.6–11.3), 5.2 (4.7–5.3)]. Thus, legs in females, in relation to other Psechrus species, quite short: FEM-I+MTT-I/CL: 2.9–3.0.
Palpal claw with 15 (13–15) teeth.
Spination. Palp: 131 (131), 110{010} (110,010), 1101 (1101), 1014 (1014); legs (—except for patella— variable, only most common states noted): femur I 567{566} (566,655), II 656{556} (566) III 555 (555), IV 555 (555,554); patella I–IV 000; tibia I 4038{3038} (3038), II 3038 (3038), III 3034 (3034,3035), IV 3036{3035} (3036,3035); metatarsus I 3037{3035} (3037,3035), II 3035 (3037,3035), III 3035 (3035), IV 3034 (3034,3035).
Copulatory organ (see also diagnosis and general description of himalayanus -group). Spermathecal heads (Fig. 49b) shorter than in P. vivax sp. nov. (but in P.vivax only two ♀♀ available). MS smooth and glossy (Fig. 88n). Slit sense organs and epigynal muscle sigilla outside epigynal field (Fig. 49a).
Primordial copulatory organ. Pre-epigyne: Similar to P. vivax sp. nov. in shape of pre-MS. The latter almost as long as broad and with curved anterior margins (Figs 49d, 51d). Distinguished by the broader anterior part of pre- MS (Fig. 49d).
Pre-vulva: Similar to P. vivax sp. nov. Distinguished by the more voluminous pre-spermatheca and the less extending pre-SH (Fig. 49e).
Colouration of male and female (see also description for himalayanus -group and Psechrus). Median bands on carapace may be slightly serrated or not. Lateral bands narrow (ca. 0.7 diameter of PME) and not serrated. Light longitudinal line ventrally on opisthosoma continuous and rather narrow. If measured centrally on opisthosoma, its width is less than the width of one half of the cribellum (ca. 0.3–0.6 of one half of the cribellum).
Variation of copulatory organs. Females: Width of median septum varies slightly (Figs 49a, 88n). In vulva the length of SH may differ slightly (Figs 49b, 91n).
Remark: In the female SB121 from Kanchanaburi Province, Thailand, the MS (Fig. 49f) is narrower than in the specimens from Laos. The spermatheca are even a bit more compact and located closer to each other (Fig. 49g). It cannot be fully excluded that this specimen belongs to a closely related, different species. However, it is more likely that those differences fall in the range of intraspecific variation of P. jaegeri sp. nov., as they are just small in regards to interspecific differences. To confirm this, more material —especially males— from that region and from Thailand in general are required.
Distribution. Laos, Thailand (?) (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 90-94, DOI: 10.11646/zootaxa.3379.1.1, http://zenodo.org/record/6039832