New cave-dwelling armored spiders (Araneae, Tetrablemmidae) from Southwest China
Author
Lin, Yucheng
Author
Li, Shuqiang
text
ZooKeys
2014
388
35
67
http://dx.doi.org/10.3897/zookeys.388.5735
journal article
http://dx.doi.org/10.3897/zookeys.388.5735
1313-2970-388-35
9EEB8A811E5846D79A161A2271B67709
9EEB8A811E5846D79A161A2271B67709
Sinamma Lin & Li
gen. n.
Type species.
Sinamma oxycera
sp. n. from cave of Guangxi, China.
Etymology.
The generic name derives from the Latin word
"sina"
and
"-mma"
as a suffix of the genus
Tetrablemma
. The gender is feminine, with sina meaning China.
Diagnosis.
Sinamma
gen. n. differs from all known genera of
Tetrablemminae
by the presence of a tubercle on the male carapace (Figs 1G, 1E;
Lin and Li 2010
: 24, figs 19, 20) and sometimes in females (Figs 1H, 1F;
Lin and Li 2010
: 25, figs 25, 26), the strongly modified male leg I (Figs 2
C-E
;
Lin and Li 2010
: 24, fig. 22), and by the exceptionally narrow postepigastral scutum in the both sexes (Figs 1B, 1D, 3
A-C
, 19B;
Lin and Li 2010
: 25, figs 27-28).
Description.
Small (1.2-1.6), six eyes compact in a group, male carapace usually with cephalic tubercle (present or absent in female). Male leg I robust, with tubercles at tibia and metatarsus. Cheliceral horn present (absent in female), much longer than in
Brignoliella
Shear, 1978 or
Shearella
Lehtinen, 1981, but shorter than in
Tetrablemma
O. P.-Cambridge, 1873 and
Gunasekara
Lehtinen, 1981. Abdomen oval, lateral scuta
II-IV
wide in both sexes.
Bulb long pyriform, embolus simple, needle-shaped; epigynal fold narrow; postepigastral scutum exceptionally narrow; central process absent, inner vulval plate well developed, vulval stem transverse.
Remarks.
The new genus
Sinamma
gen. n. contains two species and belongs to the subfamily
Tetrablemminae
.
Sinamma
gen. n. is similar to
Shearella
by the conical cheliceral horn and the pyriform bulb in the males, and is also similar to
Gunasekara
in having strongly modified leg I in the males. However, it can be distinguished from both
Shearella
and
Gunasekara
by the carapace having cephalic tubercle in male (sometimes in female also, e.g.
Sinamma oxycera
sp. n. and
Shearella sanya
Lin & Li, 2010), the presence of a distinct inner vulval plate in the female, and by the exceptionally narrow postepigastral scutum. The only oriental genus,
Singalangia
Lehtinen, 1981, for which the male is not yet known, has entirely different ocular pattern and vulval structures compared with those of
Sinamma
gen. n. In summary,
Sinamma oxycera
sp. n. and
Shearella sanya
Lin & Li share the following synapomorphies: an obvious cephalic tubercle, a strongly modified leg I in the male, and an exceptionally narrow postepigastral scutum in the female. These features distinguish them from other tetrablemmids. The new genus
Sinamma
is therefore proposed to accommodate these two oriental species,
Sinamma oxycera
sp. n. and
Sinamma sanya
(Lin & Li, 2010), comb. n., previously considered in
Shearella
.
Composition.
Sinamma oxycera
sp. n. and
Sinamma sanya
(Lin & Li, 2010).
Distribution.
China (Guangxi, Hainan).