Trechus rira, Schmidt & Faille, 2018

Schmidt, Joachim & Faille, Arnaud, 2018, Revision of Trechus Clairville, 1806 of the Bale Mountains and adjacent volcanos, Ethiopia (Coleoptera, Carabidae, Trechini), European Journal of Taxonomy 446, pp. 1-82 : 15-17

Trechus rira sp. nov.

urn:lsid:zoobank.org:act:C77BCBF5-16DC-40A4-AD08-2403F17A0463

Figs 13 , 17 , 21 , 44

Diagnosis

Very similar to the above-described T. nanulus sp. nov. from the same mountain area, but slightly larger, with eyes smaller, pronotum less transverse, laterobasal area of pronotum more depressed, aedeagal median lobe more elongated. For differentiation from the other rather tiny species of Trechus from the Bale Mts, see key to species and the diagnosis for the respective species below.

Etymology

The specific epithet refers to the village Rira, close to the type locality of the new species.

Material examined

Holotype

ETHIOPIA: ³, Oromia, S slope Bale Mts, above Rira , alt. 3150–3250 m, 06°46′ N, 39°44′ E, Dec. 2006 ( CSCHM, registration number ZSM _COL_ 2018 _005).

Paratype

ETHIOPIA: 1 ³, same data as for holotype ( CSCHM); 11 ³³, 10 ♀♀, Oromia, Bale Mts, S slope above Rira, alt. 3240 m, 06°46′39″ N, 39°44′52″ E, 15 Dec. 2017 ( CAF, CSCHM, ZMAA).

Description

BODY LENGTH. 2.6 mm (n = 2).

PROPORTIONS (n = 2). PW/HW = 1.35–1.37; PW/PL = 1.39–1.41; PW/PBW = 1.23–1.24; EW/PW = 1.55–1.60; EL/EW = 1.30–1.36.

COLOUR AND MICROSCULPTURE. As described in T. nanulus sp. nov.

HEAD. Eyes small, tempora 1.1 times as long as eyes. Proportions of the first four antennomeres as follows: 1/1/0.9/0.8. In all other characters as described in T. nanulus sp. nov.

PROTHORAX. Pronotum moderately large, transverse, broadest portion distinctly before middle, base as wide as apical margin. Disc markedly convex. Anterior margin slightly concave with anterior angles rounded, slightly protruded. Sides rounded throughout but less markedly towards base. Laterobasal angles very obtuse, blunt at apex. Marginal gutter very narrow, slightly widened near laterobasal angles. Base straight in middle, distinctly bent anteriorly at outer quarter. Median longitudinal impression fine but distinct, not deepened near base, disappearing at apex; anterior transverse impression indistinct, smooth; posterior transverse impression very shallow, laterobasal foveae diffuse limited towards disc and sides, moderately small, smooth. Pronotum with laterobasal setae present.

PTEROTHORAX. Elytra convex on disc, in dorsal view moderately short and broad, broadest in midlength or slightly before, with shoulders fully rounded; broadly rounded at apex. Striae impunctate, parascutellar stria absent, striae 1–5 indistinct (stria 1 absent in the paratype specimen), striae 6–7 absent, stria 8 moderately impressed from level of the middle group of the marginal umbilicate pores towards apex. All intervals flat. Recurrent preapical stria deep, curved in front, directed to the fifth stria. Third stria with two setiferous dorsal pores, the anterior one between anterior elytral fifth and quarter, the posterior one in middle, and with preapical seta situated at the apical anastomosis of second and third striae, slightly closer to the elytral apex than to the suture. Number and positions of the setae of the marginal umbilicate series as in Trechus s. str.

LEGS. As described in T. nanulus sp. nov.

MALE GENITALIA. EL/AL = 3.28–3.29 (n = 2). Aedeagal median lobe small, moderately elongated, in lateral view almost evenly bent throughout; apical lamella moderately long with apex roundly delimited; basal bulb and sagittal aileron average. Endophallus with copulatory piece narrowly triangular, arcuate towards apex, in lateral view more strongly sclerotized on dorsal side.

Distribution

Known only from the southern slope of the Bale Mts, above Rira village, at an altitude of approx. 3200 m.

Figures

Figs 13–16. Trechus spp., habitus. 13. T. rira sp. nov., holotype. 14. T. iridescens sp. nov., holotype. 15. T. oppositus sp. nov., paratype, ³. 16. T. bombi sp. nov., holotype.

Figs 17–20. Trechus spp., head, pronotum. 17. T. rira sp. nov., holotype. 18. T. iridescens sp. nov., holotype. 19. T. oppositus sp. nov., paratype, ³. 20. T. bombi sp. nov., holotype.

Figs 21–24. Trechus spp., elytra. 21. T. rira sp. nov., holotype. 22. T. iridescens sp. nov., holotype. 23. T. oppositus sp. nov., paratype, ³. 24. T. bombi sp. nov., holotype. The arrows point to the insertions of the discal setae and the preapical seta.

Figs 37–56. Trechus spp., aedeagal median lobe, left lateral view (37, 39, 40, 42, 44–45, 47–48, 50, 52–53, 55–56) and dorsal view (38, 41, 43, 46, 49, 51, 54). 37–38. T. mattisi sp. nov., paratype. 39. T. transversicollis sp. nov., holotype. 40–41. T. minitrechus sp. nov., paratype. 42–43. T. nanulus sp. nov., paratype. 44. T. rira sp. nov., holotype. 45–46. T. iridescens sp. nov., holotype. 47. T. relictus Magrini, Quéinnec & Vigna Taglianti, 2012, specimen from brook valley above Goba. 48–49. T. oppositus sp. nov., paratype. 50–51. T. harryi sp. nov., paratype. 52. T. dodola sp. nov., holotype. 53–54. T. adaba sp. nov., paratype. 55. T. harenna sp. nov., paratype. 56. T. bombi sp. nov., holotype.