Trechus damchungensis Deuve, 1997

Schmidt, Joachim, 2009, Taxonomic and biogeographical review of the genus Trechus Clairville, 1806, from the Tibetan Himalaya and the southern central Tibetan Plateau (Coleoptera: Carabidae: Trechini) 2178, Zootaxa 2178 (1), pp. 1-72 : 37-38

Trechus damchungensis Deuve, 1997

( Figs. 34 , 52, 53, 57 )

Catalogue: Trechus damchungensis Deuve, 1997: 141 . Locus typicus: South Central Tibet, Damzhung County, Largeh La, 5200 m (= Largen La or Lhachen La Pass N Damzhung).

Type material: Holotype male, with label data “ HOLOTYPE ”, “ Tibet 5.VII.97 Largeh La 5200 m A.

Wrzecionko”, “ Trechus damchungensis n. sp. Holotype Th. Deuve det. 1997” ( MNHN). Paratypes: 2 males, each with label data “CHINA-N. TIBET, Tangula Shan Mts., Tangula Pass 5100–5300 m, 8.–11.7.97, leg. A. Wrzecionko ”, “ PARATYPE ”, “ Trechus damchungensis n. sp. Th. Deuve det. 1997” ( CSCHM) .

Identification: See key above.

Relationships: The complete reduction of the basal velum of the aedeagal median lobe on the one hand and the elongation of the median lobe distal half on the other hand are both doubtless synapomorphies of the species T. dacatraianus and T. damchungensis , and suggest a sister species relationship.

Distribution and geographical variation: Fig. 99 . This species is hitherto known only from the type series which comprises specimens from two geographically well separated localities: 1) Three males from the Lhachen La pass of the central Nyainqentanglha Shan Massif, approximately 12 km northeast of Damzhung, and 2) altogether 30 specimens from the Tangula pass of Tangula Shan Massif at the Tibet-Quinghai border ( Deuve 1997). A careful restudy of three of the type specimens (the holotype from Lhachen La and two of the paratypes from Tangula) let me conclude tentatively that both the populations belong to distinct species or subspecies. Although almost identical in external characters, the shape of the aedeagus differs between the holotype and the two investigated paratypes: The median lobes of the latter are more elongated towards the apex, with ventral side more strongly convex in the middle, and with the upwardly directed hook of the terminal lamella longer (see Figs. 52, 53 ). However, study of more comprehensive material is required before taxonomic conclusions can be drawn.

Habitat: Higher alpine zone; vertical distribution approximately 5000–5300 m.

Figures

FIGURE 99. Map of Southern Central Tibet showing distribution of species of the Trechus wrzecionkoi group (white circles), of the Trechus dacatraianus group (white squares), of the Trechus solhoeyi group (black circle), and of the Trechus chaklaensis group (black square). 1, T. wrzecionkoi Deuve, 1996. 2, T. martinae sp. n. 3, T. korae sp. n. 4, T. damchungensis Deuve, 1997. 5, T. hodeberti Deuve, 1997. 6, T. bastropi sp. n. 7, T. mieheorum sp. n. 8, T. solhoeyi sp. n. 9, T. chaklaensis sp. n.

FIGURES 28–35. Head, pronotum. Fig. 28, Trechus pumoensis Deuve, 1997, paratype, male. Fig. 29, T. eremita sp. n., paratype, female. Fig. 30, T. tilitshoensis Schmidt, 1994, paratype, male. Fig. 31, T. aedeagalis sp. n., paratype, male. Fig. 32, T. antonini Deuve, 1997, non-type female specimen from Lhachen La. Fig. 33, T. yeti sp. n., paratype, male. Fig. 34, T. cf. damchungensis Deuve, 1997, paratype, male from Tangula Pass. Fig. 35, T. hodeberti Deuve, 1997, non-type female specimen from Lhachen La.

FIGURES 52–64. Aedeagal median lobe with sclerotized portions of internal sac in lateral view (Figs. 52–56, 60–63; Figs. 52, 54, 55, 60, 61, 63 in addition with parameres) and in dorsal view (Figs. 57–59, 64). Fig. 52, Trechus damchungensis Deuve, 1997, holotype. Figs. 53, 57, T. cf. damchungensis Deuve, 1997, paratype from Tangula Pass. Fig. 54, T. mieheorum sp. n., paratype. Figs. 55, 58, T. bastropi sp. n., paratype. Fig. 56, T. hodeberti Deuve, 1997, nontype specimen from Lhachen La (= locus typicus). Figs. 59, 60, T. solhoeyi sp. n., paratype. Fig. 61, T. yeti sp. n., paratype. Fig. 62, T. budhaensis sp. n., paratype. Fig. 63, 64, T. rolwalingensis sp. n., paratype.