Tachyina (Scolistichus), Boyd, Olivia F. & Erwin, Terry L., 2016

Boyd, Olivia F. & Erwin, Terry L., 2016, Taxonomic review of New World Tachyina (Coleoptera, Carabidae): descriptions of new genera, subgenera, and species, with an updated key to the subtribe in the Americas, ZooKeys 626, pp. 87-123 : 109-110

Taxon classification Animalia Coleoptera Carabidae

Subgenus Scolistichus subgen. n.

Type species.

Meotachys riparius sp. n.

Diagnosis.

Pronotum and elytra with fine, linear, transverse microsculpture; pronotum quadrate; mesepisternum without fovea(e); elytron with smooth margin and 8 micropunctulate interneurs, 4-7 not extended to apex; apical recurrent groove rudimentary, continuous with i3.

Description.

Size. ABL = 2.3-2.35; SBL = 2.475-2.55; TW = 1.05-1.075 mm.

Form. Elongate, subdepressed.

Color. (Fig. 2D) Dark rufous to piceous or bicolored, with head and pronotum lighter.

Microsculpture. Microsculpture of anterior part of head coarse, scaly, isodiametric; pronotal and elytral microsculpture transverse, linear; elytral surface with slight iridescence.

Head. Mentum bifoveate; frontoclypeal suture very faint, with shallow lateral impressions.

Prothorax. (Fig. 3D) Pronotum quadrate; basal section triangular, posterior margin with short rugae; basal transverse impressions well-defined, punctate, interrupted by shallow basal excavation; thin medial furrow emerging from basal excavation not reaching anterior margin of pronotum; anterior convergent impressions short, thin, effaced medially; basal protarsomere of male with prominent dentiform medial expansion.

Pterothorax. Elytral margins smooth; elytron (Fig. 5D) with 8 micropunctulate interneurs; i4-7 not reaching apex; i8 (Fig. 4D) curvy and deeply impressed in apical half, abruptly bent around Eo5+6 and Eo7; ARG (see Fig. 1E) rudimentary, continuous with i3; elytral apex with raised interval between i8 and ARG.

Genitalia. Not examined.

Distribution.

Known from localities across the Amazon basin, from the upper Rio Negro system to the Rio Napo in Ecuador and northeastern Perú, and the lower Solimões River near Manaus.

Derivation of name:

Masculine. From the Greek skolios (= “crooked”), and stíchos (= “line”/“row”), in reference to the diagnostic curved 8th interneur.