Fedorenko, Fedorenko, 2019

Fedorenko, D. N., 2019, A revision of Amphimenes (Coleoptera: Carabidae: Lebiini), Russian Entomological Journal 28 (3), pp. 233-250 : 234

Amphimenes Bates, 1873

Bates, 1873: 322; Jedlička, 1963: 366; Habu, 1964: 472; 1967: 113; 1982: 90; Fedorenko , 2010: 18; 2014: 310.

Type-species: Amphimenes piceolus Bates, 1873 (by monotypy).

REDESCRIPTION. Unnecessary here, except for some features not mentioned before, including the following leg characters: (1) profemur with a ventrobasal tubercle, (2) mesotrochanter ventrally (posteriorly) with a very fine longitudinal ridge, (3) mesotibia minutely tuberculate along apical 1/2–2/3 inner margin; and (4) a pointed tubercle at middle of its wider, mesal, part of the metacoxa. For details see below.

COMMENTS. Fedorenko [2010] arranged all species into five species groups: the rugulipennis -group, the piceolus -group, the medius -group, the rufipes -group, and the planicollis -group; the former two groups are arboricolous and the remainder include soil-dwelling species. The planicollis - group was then [ Fedorenko , 2014] subdivided into the nominal subgroup and the brunneus -subgroup, with the rufipes - group being considered as a subgroup of the planicollis - group. All these groupings are treated as separate species groups below, except that the subgenus Amphinemes subg.n. is introduced for the rugulipennis -group.

Out of the generic characters mentioned above, the profemoral tubercle is more or less distinct in A. medius (the medius -group), A. femoralis sp.n. (the brunneus -group), three of four species of Amphinemes subg.n., and A. (Amblops) marginicollis sp.n.

The mesotrochanteral ridge adjoins or almost adjoins apical trochanteral seta in almost all Amphimenes species for which males are known. It is longest yet slightly tuberculate apically in A. reflexicollis while more or less shortened and/or modified into a minute preapical tubercle to denticle in most other congeners, being combined with vestigial or totally reduced seta in all species but two. These have no ridge/ tubercle, but the seta is well-developed ( A. planipennis ) or barely shortened ( A. femoralis sp.n.). This may suggest that the seta was gradually reduced as the ridge developed in course of morphological evolution. Accordingly, the pattern observed in A. planipennis and A. femoralis sp.n. could be recognized as plesiomorphous for the genus, and a minute tubercle or nearly indistinct ridge — since the two characters are combined with vestigial or missing seta — as secondary reductions.

The mesotibial tubercles are minute and range between species in number, from mostly four ( A. bicoloripes sp.n., A. femoralis sp.n., A. konplongensis sp.n., A. marginicollis sp.n., A. medius , A. micros , A. planicollis , A. reflexicollis ) or five ( A.acutipennis sp.n., A. basipunctatus sp.n., A. planipennis , A. similis sp.n.) through three ( A. gracilis , A. maculatus , A. ruficollis sp.n.) to one ( A. piceus , A. subcostatus sp.n.) or none ( A. giganteus ).

Most species have the umbilical seta series (USS) consisting of 15 setae/setigerous pores ( US) that runs on elytral interval 9; these are arranged into two groups, anterior, or posthumeral (nine setae included), and posterior, or postmedian (six setae). The USS groundplan seems to include these groups more or less widely separated, with US 6, US 8 and US 11 approximating to or touching stria 9 (the piceolus - group). The members of the subgenus Amblops are similar, except for setigerous pores being large, barely smaller than the width of interval 9. The subgenus Amphinemes subg.n. is farther advanced due to the anterior and posterior pore groups more widely gaped in its members, with US 6, US 8 and US 11 adjoining stria 9.

In most soil-dwelling species, USS apparently evolved toward a despecialized condition defined by US becoming continuous or almost so, less oscillating across interval 9, and additional US appeared. Most of these species have retained 15 US, whereas the rest have US increased to either 17–18 ( A. basipunctatus sp.n., A. reflexicollis ) or 16–19 ( A. konplongensis sp.n.), or 20–21 ( A. acutipennis sp.n.) in number. But A. giganteus which is closely related to A. acutipennis sp.n. has retained nearly groundplan USS pattern.