The lace-sheet-weavers — a long story (Araneae: Psechridae: Psechrus)
Author
Bayer, Steffen
text
Zootaxa
2012
2012-07-04
3379
1
1
170
https://biotaxa.org/Zootaxa/article/view/zootaxa.3379.1.1
journal article
20740
10.11646/zootaxa.3379.1.1
8ea1bd82-21db-4726-8d2a-be5866734ea0
11755334
6039832
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.
FIGURES 28a–d.
Psechrus khammouan
, from Laos, Khammouan Prov. a–c ♂ holotype SB 1038. d ♂ SB 381. a–c ♂ palp (a prolateral, b ventral, c retrolateral view). d ♂ left palpal femur, retrolateral view.
FIGURES 29a–e.
Psechrus khammouan
, from Laos, Khammouan Prov., ♀ copulatory organ. a–c ♀ paratype SB 1040. d–e ♀ SB 379. a, e Epigyne, ventral view. b, d Vulva, dorsal view. c Schematic course of internal duct system. CD: Copulatory duct; EF: Epigynal field. EM: Epigynal muscle sigilla; FD: Fertilisation duct; LL: Lateral lobe; MS: Median septum; SBA: Spermathecal base; SH: Spermathecal head; SO: Slit sense organ; W: Wrinkles anteriorly in EF.
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
).