Contribution to the Knowledge of the Rakantrechus Complex (Coleoptera, Carabidae, Trechini), with Description of a New Subgenus and a New Species of the Genus Nipponaphaenops S. Uéno, 1971 from Northwestern Shikoku, Western Japan Author Karaoğlan, Beliz Bahar Author Yekedüz, Emre Author Yazgan, Satı Coşkun Author Mocan, Eda Eylemer Author Köksoy, Elif Berna Author Yaşar, Hatime Arzu Author Şenler, Filiz Çay Author Utkan, Güngör Author Demirkazık, Ahmet Author Akbulut, Hakan Author Ürün, Yüksel text Bulletin of the National Museum of Nature and Science. Series A, Zoology 2022 Zoology 2022-08-22 48 3 119 138 http://dx.doi.org/10.1080/1750743X.2024.2370231 journal article 10.50826/bnmnszool.48.3_119 2434-091X 12760044 Subgenus Nipponaphaenops S. Uéno, 1971 Diagnostic characters. As far as known from the type species, this subgenus is different from another subgenus in the following character states; larger ( BL : 5.8–7.3 mm ); head more macrocephalic ( PW / HW 1.14 – 1.27 , PL / HL 1.08 – 1.20 ), more elongate ( HW /HL 0.76–0.84); frontal furrows abbreviated posteriorly; tempora to genae only with a genal seta; penultimate labial palpomere about 1.15 times longer than ultimate one, with two subapical setae on the external face of the former reduced in size ( Fig. 1o ); antennae longer, slenderer, more than a half longer than elytra; pronotum with hind angles with acute denticle produced posteriad; posterior latero-marginal setae of pronotum absent; elytra more elongate ( EL / EW 1.48 – 1.57 ), with longer prehumeral borders more arcuately sinuate; pore 1 of the marginal umbilicate series of elytra closer to marginal gutter and more distant from elytral base (U1 17.2–18.8), pore 4 of the series more distant from elytral base (U4 33.6–36.1); elytral discal seta of the external series more inwardly (in interval 4), more anteriorly (basal 6/11–10/17) positioned; legs longer and slenderer; ventrites 4–6 each with two or three pairs of paramedian setae ( Fig. 2l ) . Taxonomic notes. This subgenus is presently monotypic. One of the diagnostic characters of this subgenus, posteriorly abbreviated frontal furrows, makes the type species, in combination with the so-called aphaenopsian body form, a unique truly aphaenopsian representative within the members of the Trechiama Phyletic Series, as far as the currently included members of the series are considered ( Uéno, 1978 , p. 9). Geographic range. Ohnogahara Karst, west-central area of Shikoku, southwestern Japan ( Fig. 7 ).