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 libelti
Kulczy
ń
ski, 1908, stat. nov.
Figs 5a–e
,
6a–e
,
82a
,
84b–c
,
87b
,
90b
Psechrus libeltii
Kulczy
ṅski 1908: 561, pl. 23, fig. 31 (Description and illustration of
♀
). [
Syntypes
:
2 ♀♀
(light one SB 337, dark one SB 338), 2 s.a.
♂
(the one just before final moult SB 339, other one SB 340), all from
INDONESIA
:
Sumatra
,
Sumatera Selatan Province
: Palembang; Dr. S. Libelt leg. before 1908; 46/51U; MIZ, all type material examined].
Berland and Berland 1914: 133
.
Hogg 1914: 56
;
1915: 436
.
Fage 1929: 360
.
Reimoser 1929: 132
.
Lehtinen 1967: 261
.
Levi 1982: 125
(Syn. with
P. singaporensis
, rejected).
Psechrus argentatus
—
Simon 1901: 47
, misidentified.
Psechrus libelti
—
Bonnet 1958: 3804
(Emendation).
Platnick 1989: 428
.
Psechrus singaporensis
—
Levi 1982: 125
, figs 40–53, ad part, figs 42–43, 48–53 misidentified (figs 48–51: illustration of
♀♀
).
Jocque and Dippenaar-Schoeman 2006: 219
, figs 86a–f (Illustration of
♂
and
♀
, misidentified).
Additional material examined
(
2 ♂♂
,
8 ♀♀
).
THAILAND
:
Phuket Province
:
Phuket
,
Ton Sai
waterfall,
N 8°01'
,
E 98°25'
, forest
;
M. Andersen
,
O. Martin
&
N. Scharff
leg.
12.X.1991
;
1 ♀
(
SB 611
), ZMUC 4537
.
Songkhla Province
:
Hat Yai
,
Khao Khor Hong
, small mountainous area behind
Prince of Song Khla University
campus, ca.
N 7°00'30''
,
E 100°30'40''
, ca.
140 m
;
B. Phongsee
leg.
15.IX.2005
;
1 ♂
(
SB203
, deformed, presumably died immediately after final moult),
SMF
.
MALAYSIA
:
Pahang Province
:
No
further details
;
Coll. Sherriffs
; Tilg.
27-9-1962
;
1 ♀
(
SB 1004
), ZMUC 5726.
Selangor Province
:
Templer’s Park, secondary forest, under roof of hut;
C.L. Deeleman
leg.
03.XII.1990
;
1 ♀
(
SB130
)
,
Deeleman Coll.
in RMNH.
Borneo
:
Sabah Province
:
Danum Valley
(ca.
70 km
W of Lahad Datu
), ca.
N 5°02'
,
S 117°45'
, primary lowland rainforest; [observation no. 905]
;
P. Koomen
leg.
13.
IV
.2003
;
1 ♀
(
SB 1141
, checked via photos of dorsal and ventral habitus and epigyne kindly provided by
Peter Koomen
), [Photos were made in the field, specimen was released afterwards]
.
INDONESIA
:
Sumatra
:
‘
Kouan Dam’
;
Burbon
leg. 1913–1916;
1 ♀
(
SB 330
), MNHN AR20193
.
Nanggroe Aceh Darussalam Province
:
Gunung Leuser National Park
, in tunnel next to cacao plantation
;
P.R. & C.L. Deeleman
leg.
03.I.1984
;
1 ♀
(
SB 109
), Deeleman Coll. in RMNH
.
Sumatera Barat Province
:
Mentawei Islands
,
Sipora
;
Coll. Roewer
;
C.F. Roewer
det.;
1 ♀
(
SB 87
),
SMF 2565
.
BRUNEI DARUSSALAM
:
Tutong District
:
Tasek Merimbum Heritage Park
, area C1, 45 km
W of Bandar Seri Bagawan
,
N 4°35'39''
,
E 114°40'25''
,
30 m
, secondary peat forest
;
C. Griswold
&
J.K.H. Koh
leg.
13.–14.X.2009
, at night;
TM 002
;
1 ♀
(
SB 969
), CAS 9036347.
Doubtful locality:
INDIA
?
[sic; Remark: If really India, then
Nicobar Islands
; Up to now representatives of
argentatus
-group have never been recorded in (continental-) India or on Sri Lanka];
Hassan
leg.;
1 ♂
(
SB 612
), ZMUC 5720
.
Doubtful material examined.
MALAYSIA
: Borneo:
Sarawak Province
:
Gunung Pueh (
Mt. Poi
);
E. Mjöberg
leg. 1920–1925;
1 juv.
(
SB 1160
), AMNH
.
PHILIPPINES
:
Palawan Province
:
Balabac Island
;
Dalawan Bay
; ‘
Noona Dan Expedition
61–62’, leg.
09.X.1961
;
1 ♂
(
SB 1006
), ZMUC 5723
.
Revised diagnosis.
Males and females similar to
P. argentatus
(
Doleschall, 1857
)
(see diagnostic character states described for
argentatus
-group above). Males with conductor (C) more than half as long as embolus (E) (
Figs 6b–d
). Females with median septum (MS) almost as long as broad and with continuous lateral margins (
Figs 5a–b
). Epigynal field (EF) less than three times longer than MS.
Description.
Male:
Body and eye measurements. Carapace length 4.8–6.9, carapace width 3.5–5.2, anterior width of carapace 2.2–3.5, opisthosoma length 5.7–10.2, opisthosoma width 1.7–3.3. Eyes: AME 0.31–0.47, ALE 0.33–0.45, PME 0.33–0.45, PLE 0.32–0.45, AME–AME 0.17–0.24, AME–ALE 0.06–0.14, PME–PME 0.19–0.27, PME–PLE 0.27–0.31, AME–PME 0.44–0.46, ALE–PLE 0.41–0.43, clypeus height at AME 0.84–0.86, clypeus height at ALE 0.68–0.77.
Cheliceral furrow with three promarginal and four retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423 or 1243. Palp 8.2–9.0 [2.7–3.0, 1.1–1.3, 1.1–1.2, 3.3–3.5], I 68.0–81.0 [17.8–20.9, 2.7–3.3, 18.0–21.3, 20.7–25.4, 8.8–10.1], II 46.9–56.7 [11.9–15.6, 2.4–2.9, 12.1–14.3, 13.8–16.9, 6.7–7.0], III 29.9–36.1 [8.5–10.4, 1.7–2.1, 7.3–8.8, 8.5–10.3, 3.9–4.5], IV 47.5–55.5 [12.0–13.7, 2.0–2.6, 12.0–13.9, 14.4–17.2, 7.1–8.1].
Spination. Palp: 131 (141), 110, 1101; legs: femur I 667 (878), II 767 (766) III 545 (656), IV 655 (665); patella I–IV 000; tibia I–II 3036 (3038), III 3134 (3136), IV 3036 (3136); metatarsus I 3037 (3035), II–III 3035, IV 3034. Palpal femur modified with ventral extension. The latter rather pointed (
Fig. 6e
).
Copulatory organ. As in diagnosis and general description for
argentatus
-group.
Female:
Body and eye measurements. Carapace length 6.3–9.2, carapace width 4.1–6.5, anterior width of carapace 2.3–3.9, opisthosoma length 8.1–15.9, opisthosoma width 3.5–7.7. Eyes: AME 0.41–0.46, ALE 0.41–0.50, PME 0.43–0.50, PLE 0.42–0.50, AME–AME 0.27–0.37, AME–ALE 0.07–0.14, PME–PME 0.32–0.37, PME–PLE 0.30–0.52, AME–PME 0.46–0.71, ALE–PLE 0.47–0.71, clypeus height at AME 0.94–1.78, clypeus height at ALE 0.78–1.49.
Cheliceral furrow with three promarginal and four retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp: 8.1–11.0 [2.8–3.9, 1.1–1.5, 1.5–2.0, 2.7–3.6]; Legs: I 54.5–69.6 [14.5–18.9, 2.9–4.1, 15.2–19.6, 15.2–19.5, 6.7–7.5], II 38.2–49.5 [10.8–14.4, 2.6–3.5, 10.3–12.8, 10.4–13.4, 4.1–5.4], III 25.8–34.2 [7.4–10.3, 1.8–2.7, 6.4–8.5, 7.0–8.8, 3.2–3.9], IV 39.1–52.2 [11.2–15.0, 2.3–3.2, 10.3–13.6, 10.8–14.2, 4.5–6.2].
Palpal claw with 12–14 teeth.
Spination. Palp: 141 (rarely 131), 110, 1101, 1014; legs (—except for patella— variable, only most common states noted): femur I 768 (667), II 767 (777) III 656 (756), IV 765 (856); patella I–IV 000; tibia I–II 3036, III 3134 (3136,3035), IV 3034 (3134); metatarsus I 3035, II 3035 (3037), III 3035, IV 3034 (3035).
FIGURES 5a–e.
Psechrus libelti
, ♀ syntypes from Indonesia, Sumatera Selatan Prov. a, c–d ♀ SB 338. b, e ♀ SB 337. a–b Epigyne, ventral view. c, e Vulva, dorsal view. d Schematic course of internal duct system.
Copulatory organ (see also diagnosis and general description of
argentatus
-group). Lateral margins of MS converging anteriorly (
Figs 5a–b
,
87b
). Slit sense organs (SO) may be within or outside EF, epigynal muscle sigilla generally associated with EF.
Colouration of male and female. See description for
argentatus
-group and
Psechrus
.
Variation of copulatory organs.
Males: No statement possible, because only two individuals have been examined. One of which with deformed tegulum (T). In females the shape of MS varies. In some specimens the lateral margins are slightly more curved (
Fig. 5b
). Further, in some specimens the spermathecae and the lateral parts of CD are shifted somewhat in dorsal direction (
Fig. 5e
). Directions of SH may differ slightly (
Figs 5c,e
,
90b
).
Remarks:
The
two adult
males (SB 203, SB 612) examined herein were assigned to
P. libelti
because their palps show the same diagnostic character states as the subadult male
syntype
SB 339. This latter specimen must have been collected just a few hours before adult moult. The bulb structures, including the long C, are visible through the cuticle (
Fig. 84b
).
This species is removed from synonymy with
P. singaporensis
Thorell, 1894
because it shows clear differences in copulatory organs, which indicate that it does not even belong to the same species-group (
singaporensis-
), but to the
argentatus
-group.
Levi (1982)
synonymised this species with
P. singaporensis
, possibly based his decision on cursory similarities of MS of both species. He in fact illustrated the clear differences in vulvae (figs 44, 46 cf. figs 48, 50), but misinterpreted them. He probably had overseen the bulb structures of the s.a. male
syntype
(SB 339) visible through the cuticle, which additionally indicate that this species is more closely related to
P. argentatus
than to
P. singaporensis
. In the paragraph of his note concerning the synonymy he states that his decision “may be wrong” and that the females in his figs 48–51 “possibly belong to
P. argentatus
” (
Levi 1982
)
.
The male from Balabac,
Philippines
(SB 1006, details see above) has a distinctly shorter cymbium (in relation to T) than the other males (and the males of
argentatus
examined herein). Its C is only slightly more than half as long as E. As long as there are no females available from that island, the identification of this specimen remains doubtful.
FIGURES 6a–e.
Psechrus libelti
, ♂ palp and palpal femur. a–c, e ♂ SB 612 from India?, Nicobar Islands? d ♂ SB 203 from Thailand, Songkhla Prov. a–d ♂ palp (a prolateral, b, d ventral, c retrolateral view). e ♂ left palpal femur, retrolateral view. Remark: In Fig. 6d tegulum deformed (specimen presumably died directly after final moult).
Distribution.
Thailand
[Southern part],
Malaysia
,
Indonesia
[
Sumatra
],
Brunei Darussalam
(
Figs 99–100
).