Systematic review of a new orb-weaving spider genus (Araneae: Araneidae), with special reference to the Australasian-Pacific and South-East Asian fauna
Author
Joseph, Mathew M.
Author
Framenau, Volker W.
text
Zoological Journal of the Linnean Society
2012
2012-09-28
166
2
279
341
http://dx.doi.org/10.1111/j.1096-3642.2012.00845.x
journal article
10.1111/j.1096-3642.2012.00845.x
0024-4082
5408725
PLEBS ROSEMARYAE
SP. NOV.
ROSEMARY’ s GRASS ORB- WEAVER (
FIGS 29–31
)
Types:
Holotype
.
♂
from
Queensland
(
Australia
),
Chujeba Peak
,
7 km
south-west of
Redlynch
,
16°56
′
S
,
145°39
′
E
,
14–16.xii.1989
,
G. Monteith
&
G. Thompson
,
1000 m
asl
(
QM
S88992
)
.
Paratypes
.
♂
, data as holotype (
QM
S41583
)
;
♀
from
Queensland
,
Mount Edith
,
Lamb Range
,
17°06
′
S
,
145°38
′
E
,
11.x.1982
,
G. Monteith
,
D. Yeates
&
G. Thompson
(
QM
S84232
)
.
Other material examined:
Sixteen males,
57 females
, and
24 juveniles
from 29 records (Appendix S1).
Diagnosis:
Based on somatic characters and overall morphology of the pedipalp,
P. rosemaryae
males bear strong resemblances to
P. arletteae
.
However, there are subtle differences in the pedipalp morphology, which differentiate the two species. For instance, the apical tips of the median apophysis are comparatively smaller in
P. rosemaryae
than in
P. arletteae
(compare
Figs 24A
and
13A
). Females of
P
.
rosemaryae
have an epigynal scape that is convoluted at the base similarly to those of
P. cyphoxis
and
P. opacus
. However, the scape of
P. rosemaryae
differs from that of
P. cyphoxis
in the incidence of a single curve at its base (
Fig. 30E, F
) in all observed specimens as opposed to multiple convolutions in
P. cyphoxis
(
Fig. 19E
). Additionally, the scape of
P. cyphoxis
has a wrinkled texture along its entire length and tapers gradually towards the distal end, whereas in
P. rosemaryae
, the scape is generally smooth in appearance and tapers rather abruptly towards the distal end (compare
Figs 19E
and
30E, F
). The major difference in the scape morphology between
P. rosemaryae
and
P. opacus
is in the degree of the basal curvature. It is sharp and prominent in
P. rosemaryae
(
Fig. 30E, F
) in comparison to a shallower curve in
P. opacus
(
Fig. 24E
). Further, in
P. rosemaryae
, the scape has an abrupt tapering towards the apex in contrast to the gradual tapering observed in
P. opacus
(compare
Figs 30E, F
and
24E
).
Figure 29.
Plebs rosemaryae
sp. nov.
A, B, male holotype from Chujeba Peak, Redlynch, Queensland (QM
S88992
). A, dorsal view; B, ventral view. C, D, female from Mount Edith, Lamb Range, Queensland (QM
S84232
). C, dorsal view; D, ventral view. E, female from Bellenden Ker, Queensland (QM
S26358
), dorsal view. F, female from Bellenden Ker, Queensland (QM
S26351
), dorsal view. Scale bar = 2.0 mm in A, B; 1.0 mm in C- F.
Figure 30.
Plebs rosemaryae
sp. nov.
A–C, pedipalp of male holotype from Chujeba Peak, Redlynch Queensland (QM
S88992
). A, ventral view; B, dorsal view; C, apicoventral view. D, epigyne of female from Bellenden Ker, Queensland (QM
S26351
), dorsal view. E, epigyne of female from Mount Edith, Lamb Range, Queensland (QM
S84232
), ventral view. F, epigyne of female from Bellenden Ker, Queensland (QM
S26351
), ventral view. Scale bar = 0.2 mm in A- C; 0.16 mm in D; 0.3 mm in E, F.
Figure 31.
Distribution records of
Plebs patricius
sp. nov.
(open circles) and
Plebs rosemaryae
sp. nov.
(closed circles) in Australia.
Description
Male:
Based on
holotype
. Carapace light orangebrown, patches of dark pigmentation along the lateral margins and a central patch of dark pigmentation covering the entire length of fovea (
Fig. 29A
); carapace glabrous; two light brown bristles behind PE; fovea cross-shaped, longer than wide. Chelicerae yellow-brown, a small band of dark pigmentation at the proximal dorsal surface; a few black setae mainly in the apical half. Sternum orange-brown, with scattered dark pigmentation; a weak cover of brown bristles. Abdomen dorsally glabrous, a very weak cover of white setae; covered with off-white pigmentation, interspersed with a greenish-brown folium (
Fig. 29A
); venter with greenish-brown pigmentation (
Fig. 29B
); a weak cover of white setae. Spinnerets light brown, posterior lateral spinnerets extending beyond abdomen. Legs orange-brown, weakly spined, more spination on patella and metatarsus. Coxa of leg IV with three stout setae ventrally. Leg formula 1
>
2
>
4
>
3. Pedipalps (
Fig. 30A–C
): apex of the median apophysis curved towards cymbium and with two sclerotized apical tips, base sinuous; tegulum with a prominent apical protrusion; terminal apophysis with sinuous base and a marginally sclerotized tip; embolus bulbous at the base; conductor ovate.
Dimensions
: total length (excluding chelicerae) 4.18. Carapace length 2.0, width 1.7, height 0.58.
Eyes: AME 0.19, ALE 0.15, PME 0.17, PLE 0.12, AME–AME 0.08, AME–ALE 0.08, PME–PME 0.02, PME–PLE 0.19, PLE–ALE 0.02, MOQ width front 0.38, MOQ width back 0.35, MOQ length 0.31, eye group width 0.81. Sternum length 0.97, width 0.73. Abdomen length 2.55, width 1.39. Pedipalp: femur 0.30, patella + tibia 0.48, tarsus 0.79, total 1.57. Leg I: femur 2.79, patella + tibia 3.03, metatarsus 2.18, tarsus 0.61, total 8.61. Leg II: femur 2.42, patella + tibia 2.55, metatarsus 1.82, tarsus 0.61, total 7.4. Leg III: femur 1.39, patella + tibia 1.21, metatarsus 0.67, tarsus 0.48, total 3.75. Leg IV: femur 2.12, patella + tibia 1.94, metatarsus 1.52, tarsus 0.61, total 6.19.
Variation
(range): TL 4.18–5.45; CL 1.33–2.42; CW 1.70–1.94; AL 2.24–3.39; AW 1.39–1.82;
N
= 6.
Female:
Based on
paratype
from Mount Edith, Lamb Range, QM
S84232
. Carapace as male, but fovea Y-shaped (
Fig. 29C
). Chelicerae and sternum as male. Abdomen with general coloration as male (
Fig. 29C
); humeral humps present; venter as male (
Fig. 29D
); the area enclosing the inverted ‘U’ pattern with brown bristles. Spinnerets light brown. Legs orange-brown with black annulations; weakly spined. Leg formula 1
>
2
>
4
>
3. Epigyne scape elongated, convoluted at the base. (
Fig. 30E, F
): spermathecae elongate ovoid (
Fig. 30D
).
Dimensions:
total length (excluding chelicerae) 6.30. Carapace length 2.18, width 1.70, height 0.77. Eyes: AME 0.19, ALE 0.12, PME 0.15, PLE 0.12, AME–AME 0.12, AME–ALE 0.17, PME–PME 0.06, PME–PLE 0.29, PLE–ALE 0.02, MOQ width front 0.44, MOQ width back 0.38, MOQ length 0.44, eye group width 1.15. Sternum length 1.15, width 0.91. Abdomen length 5.15, width 2.91. Palp: femur 0.73, patella + tibia 0.85, tarsus 0.73, total 2.31. Leg I: femur 3.03, patella + tibia 3.64, metatarsus 2.42, tarsus 0.79, total 9.88. Leg II: femur 2.91, patella + tibia 3.03, metatarsus 2.06, tarsus 0.67, total 8.67. Leg III: femur 1.33, patella + tibia 1.52, metatarsus 1.03, tarsus 0.61, total 4.49. Leg IV: femur 2.55, patella + tibia 3.03, metatarsus 2.06, tarsus 0.67, total 8.31.
Variation
(range): TL 5.88–7.09; CL 1.70–2.30; CW 1.82–2.30; AL 3.82–5.27; AW 2.12–3.94;
N
= 6. Within the overall general colour pattern, slight variations are evident ranging from a lighter (
Fig. 29F
) to a darker abdominal folium (
Fig. 29C, E
).
Distribution:
Norfolk Island
, Queensland (
Fig. 31
).
Life history and habitat preferences:
Most mature spiders were collected from October to December, although there are some records from January, April, and July.
Plebs rosemaryae
appears to be a higher elevation forest species with most records from altitudes above
800 m
.
Etymology:
The specific epithet is a matronym in honour of the senior author’s spouse Rosemary Antony.