Genus Tenomerga Neboiss, 1984

Tenomerga Neboiss, 1984: 448 (

type species: Cupes mucida Chevrolat, 1829, by original designation).

Diagnosis. Head closely covered with scaly short setae; P1 (protuberances above antennal insertions) and P2 (protuberances above the eyes) present; P3 (median protuberances) low and wide. Labrum (Fig. 5A) free, small, longer than wide. Maxilla (Fig. 5C) with 4-segmented palpi; apical palpomere with dorso-lateral sensory patch (dls). Mandibles (Fig. 5E, F) short and compact, with two apical teeth, covered with scaly setae in dorsal surface. Labium (Fig. 5B) transverse, arcuate and irregularly serrate along anterior margin; ligula consisting of 7 pairs of digitiform appendages; labial palpi (Fig. 5D) 3-segmented, with sensory patch (sp) on apical palpomere. Antennae 11-segmented, relatively long and thin, filiform. Antennomere II shortest; antennomere XI longest. Hind wings well developed, described by Lawrence et al. (2021). Pronotum quadrate, transverse; anterior angles simply arcuate (bifid in T. angulinota Wang & Hájek, 2018); posterior angles arcuate. Elytra (Fig. 4) elongate, subparallel-sided, with longitudinaly 9- or 10-rows of window punctures; window punctures round to transverse; intervals III, V, VII more or less raised. Legs short.

Male genitalia. Tergite VIII (Fig. 6A) well sclerotized, subtriangular, closely covered with minute spines, with a pair of short apodemes. Sternite VIII (Fig. 6B) moderately sclerotized, triangular, bearing short setae on apical and laretal parts, with a pair of short apodemes. Sternite IX (Fig. 6C) slightly sclerotized, large and oblong, connected with tergite IX in basal part. Tergite IX (Fig. 6C) slightly sclerotized, larger than sternite IX, closely covered with minute spines in apical part. Bifurcate process (Fig. 7F; segment X? in Morimoto 1986) well sclerotized, V- or Y-shaped, situated between tergite IX and sternite IX. Tegmen (Fig. 7A) long; parameres long, almost straight, sparsely punctate; apical hook (ap in Fig. 7A, E) present in apical part of parameres; ventro-marginal spine (vms) long and thin; basal opening (bo) oval. Penis (Fig. 7B–D) short, connected with tegmen in basal part, consisting of dorsal plate and mesal lobe; dorsal plate (dp; membranous lobe in Edwards 1953) membranous, connected with mesal lobe in basal part; mesal lobe (median lobe in Edwards 1953; penis in Hörnschemeyer 2009) longer than dorsal plate, sparsely punctate.

Female genitalia. Sternite VIII (Fig. 6D) triangular, deeply notched at apical margin, with long median strut. Tergite VIII (Fig. 6E) with a pair of short apodemes protruding from anterior margin; a pair of long projections in apical part. Ovipositor (Fig. 6F) long; stylus 2-segmented; apical segment (st2) longer than basal one (st1).

Key to species of the genus Tenomerga of East Asia

1. Elytra with 9-rows of window punctures................................................................... 2

-. Elytra with 10-rows of window punctures.................................................................. 3

2. Elytra blackish-brown, typically unicolorous......................................................... T. mucida

-. Elytra yellowish-brown, with alternating dark and pale brown markings............................... T. anguliscutis

3. Elytra blackish-brown, unicolorous................................................................ T. yamato

-. Elytra yellowish-brown, with distinct alternating dark and pale brown markings.................................... 4

4. Base of bifurcate process oval; apex of mesal lobe notched; ventro-marginal spine short, not reaching apical hook.................................................................................................... T. japonica

-. Base of bifurcate process quadrate; apex of mesal lobe shallowly concave; ventro-marginal spine long, reaching apical hook. ................................................................................................... 5

5. Anterior pronotal angles strongly acute; mesal lobe distinctly longer than dorsal plate..................... T. kurosawai

-. Anterior pronotal angles acute; mesal lobe a little longer than dorsal plate................................ T. trabecula