Kataev, Kataev, 2022

Kataev, B. M., 2022, Description of two new subgenera of Trichotichnus, with new brachypterous species from New Guinea and Sumatra (Coleoptera: Carabidae), and notes on three previously described species, Russian Entomological Journal 31 (4), pp. 373-384 : 374

KEY TO SUBGENERA OF TRICHOTICHNUS (modified from Kataev [2020]; references to figures in this paper are omitted)

1. Fronto-ocular furrows deep throughout, reaching inner margin of eyes and continuing into deep supraorbital furrows behind fusion; anterior part of supraorbital furrows before fusion shallower than its posterior part behind fusion and usually more or less isolated from it. Fronto-clypeal suture deepened, fused laterally with fronto-ocular furrows. Ligular sclerite narrow, not widened at apex, more or less parallel-sided or moderately narrowed apically. Paraglossa moderately wide or somewhat narrow, rounded apically, separated from ligular sclerite by narrow notch .................................................. Bottchrus

— Fronto-ocular furrows shallow, at most deepened only at clypeus, reaching or not reaching supraorbital furrows, occasionally only slightly visible; supraorbital furrows similar along entire length, not interrupted. Fronto-clypeal suture superficial or slightly deepened. Ligular sclerite narrow or widened at apex. Paraglossa wide or rather narrow, separated from ligular sclerite by narrow or wide notch ............................................................................. 2

2. Paraglossae narrow, notch between them and ligular sclerite wide, about as wide as each paraglossa apically. Ligular sclerite widened at apex or almost parallel-sided ......... 3

— Paraglossae wider, notch between them and ligular sclerite narrow, much narrower than each paraglossa apically. Ligular sclerite not widened at apex, at most with outer angles slightly protruded laterally ............................... 5

3. Pronotal lateral margins without setigerous pore; border of basal margin present only laterally and vaguely defined. Last visible abdominal sternite with one pair of marginal setigerous pores in male and female ............... .................................................... Allotichnus subgen.n.

— Pronotal lateral margins with one or several setigerous pores; basal margin distinctly bordered along entire length. Last visible abdominal sternite with one or two pairs of marginal setigerous pores in male and with two pairs in female ........................................................................... 4

4. Metepisternum slightly narrowed posteriorly, its anterior margin longer than inner margin. Species from mainland China........................................................ Amaroschesis

— Metepisternum markedly narrowed posteriorly, its anteri- or margin not longer than inner margin. Species from China and other countries .............. Trichotichnus s. str.

5. Elytral marginal umbilicate series continuous, consisting of 24–34 setigerous pores. Ligular sclerite markedly narrowed to apex .......................................... Parairidessus

— Elytral marginal umbilicate series consisting of 14–20 setigerous pores, with a gap at middle or, less often, without it. Ligular sclerite almost parallel-sided or slightly narrowed before apex .............................................. 6

6. Pronotal sides sinuate basally; basal margin not bordered. Head large (HWmax/PWmax more than 0.7). Microsculpture on elytral intervals distinct throughout, consisting of short or moderately long transverse meshes. Prosternum glabrous. Elytral interval 3 without setigerous pore. Metepisternum short, its anterior margin longer than or equal to inner margin ................. Neotichnus subgen.n.

— Pronotal sides rounded or almost straightly converging basally, not sinuate; basal margin distinctly bordered. Head smaller (HWmax/PWmax less than 0.7). In most species, microsculpture on elytral intervals fine, consisting of transverse lines or indistinct, prosternum with fine short setae, elytra with a discal setigerous pore on interval 3, and metepisternum elongate, its anterior margin markedly shorter than inner margin ....................... Iridessus