Trechus

Borges, P. A. V., Serrano, A. R. M. & Amorim, I. R., 2004, New species of cave-dwelling beetles (Coleoptera: Carabidae: Trechinae) from the Azores, Journal of Natural History 38 (10), pp. 1303-1313 : 1312

Key to the Azorean species of Trechus

1 Apical angle of elytra rounded.............. 2

– Apical angle of elytra pointed or sharp angled......... 6

2 Larger species, length w 3.5 mm; lateral margins of pronotum markedly sinuated before the basis, degree of pigmentation variable......... 3

– Length 3.0– 3.2 mm; lateral margins of pronotum hardly sinuated before basis; clearly dark pigmented species........... torretassoi Jeannel

3 Depigmented with a convex and ovalate facies; 3rd antennomere longer than 2nd...................... 4

– Body pigmentation variable with lighter parts; with a transverse and depressed body; 3rd antennomere subequal to 2nd............. 5

4 Aedeagus with apex of lamella slightly blunt; only in Pico.. picoensis Machado

– Aedeagus with apex of median lobe deeply curved upwards ( figure 3a ); only in Faial................ oromii new species

5 Pronotum cordiform and highly transverse (index W/L ~ 1.35), with lateral furrow very narrow............ terrabravensis new species

– Pronotum index W/L ~ 1.12; lateral furrow larger...................... montanheirorum Oromí and Borges

6 Apical angle of elytra sharp (sometimes notched), forming a small protruding point; total length 3.6–4.3 mm .......... terceiranus Machado

– Apical angle of elytra sharp (forming a right angle). Size v 3.5 mm .... 7

7 Slightly pigmented on elytra and pronotal disc; aedeagus in lateral view with apex of median lobe more or less straight and pointed ( figure 2a ); right paramere with four setae ( figure 2b ).............. pereirai new species

– Depigmented; aedeagus in lateral view with apex of the median lobe sharpened and slightly upward curved ( figure 4a ); right paramere with five setae ( figure 4b )............ jorgensis Oromí and Borges

Figures

FIG. 3. Aedeagus of Trechus oromii n. sp. (a) Median lobe, lateral view; (b) left and right parameres; (c) median lobe, dorsal view. Scale: 0.5 mm.

FIG. 2. Aedeagus of Trechus pereirai n. sp. (a) Median lobe, lateral view; (b) left and right parameres; (c) median lobe, dorsal view. Scale: 0.3 mm.

FIG. 4. Aedeagus of Trechus jorgensis Oromí and Borges. (a) Median lobe, lateral view; (b) left and right parameres; (c) median lobe, dorsal view. Scale: 0.3 mm.