Taxonomic and biogeographical review of the genus Trechus Clairville, 1806, from the Tibetan Himalaya and the southern central Tibetan Plateau (Coleoptera: Carabidae: Trechini) 2178
Author
Schmidt, Joachim
text
Zootaxa
2009
2009-08-06
2178
1
1
72
https://biotaxa.org/Zootaxa/article/view/zootaxa.2178.1.1
journal article
10.11646/zootaxa.2178.1.1
11755334
5312276
Trechus eremita
sp. n.
(
Figs. 29
,
45, 46
)
Type material:
Holotype
male, with label data “
NEPAL
oc.
Karnali Prov.
,
34 km
NE Jumla
,
Bachtal
SE Taka,
29°30’12’’N
,
82°24’20’’E
,
3800 m
,
01.VII.1999
leg.
A. Weigel
” (
NME
).
Paratypes
:
1 male
,
2 females
, with same label data as holotype (
CSCHM
,
CWG
)
.
Description:
Body length:
3.1–3.4 mm
.
Colour: Dorsal surface brown, moderately shiny, head distinctly darker than pronotum, palpi, three or four basal antennal segments and legs yellowish brown.
Microsculpture: Head with slightly engraved slightly transverse meshes on disc, and with deeply engraved almost isodiametric meshes in frontal furrows and on neck; pronotum with faintly engraved slightly transverse meshes on disc but with deeply engraved meshes throughout basal depressions. Elytra with moderately engraved slightly transverse meshes in both sexes.
Head: As described in
T. muguensis
sp. n.
Pronotum: Proportions: WP/LP = 1.18–1.26, WP/WPB = 1.35–1.43, WP/WH = 1.23–1.24, WE/WP = 1.58–1.65. In all other pronotal characters agreeing with
T. muguensis
sp. n.
Elytra: Proportion WE/LE = 1.42–1.52. Striae impunctate, two or three inner stria slightly stretched on elytral disc, absent at base and flattened on apex; fourth stria only suggested as a fine incomplete line, outer striae completely reduced. In all other elytral characters completely agreeing with
T. muguensis
sp. n.
Male genitalia: Aedeagal median lobe elongate (LE/LA = 1.63–1.65), in lateral view strongly curved behind basal bulb, almost straight in the middle portion, distinctly bent upwards at the beginning of distal quarter, with undulate curve at apex; ventral side slightly widened in middle. In dorsal view, right side of median lobe slightly widened at the beginning of distal quarter; tip of terminal lamella produced, rounded. Internal sac with sclerotized portion relatively small, strongly flattened in lateral view.
Etymology:
The specific epithet is used as a noun in apposition, and refers to the Latinized Greek word ‘eremita’, a hermit.
Identification:
In external characters almost identical to
T. franzianus
Mateu & Deuve, 1979
and the forgoing described
T. muguensis
sp. n.
, but elytral micromeshes in females not so deeply engraved. In addition,
T. eremita
sp. n.
differs from both these species by its aedeagal characters: The median lobe is more elongated than in
T. muguensis
sp. n.
, with its basal bulb not so strongly bent downwards, but with its apical portion more distinctly curved upwards. In dorsal view, the median lobe is more slender than that of
T. franzianus
, and not widened behind middle on its left side. For differentiation with the newly described species
T. aedeagalis
sp. n.
and
T. sculptipennis
sp. n.
see diagnosis of the latter below.
Relationships:
See remarks in chapter Relationships of
T. tilitshoensis
Schmidt, 1994
.
Distribution:
Fig. 98
. North slope of Sisne Himal, Western
Nepal
Himalaya
. Up to now only known from the southern side valley of Mugu
Karnali
River South East of Taka.
Habitat:
The few specimens of the
type
series were found under big stones on subalpine meadows beside a brook at an altitude of
3800 m
. However, the vertical distribution of the species truly extends to the alpine zone.