Thaumastodinae, Champion, 1924

Yoshitomi, Hiroyuki, 2019, Review of the Asian Thaumastodinae (Coleoptera, Byrrhoidea, Limnichidae), with a phylogeny of the genera, European Journal of Taxonomy 583, pp. 1-45 : 5-6

Key to genera of the subfamily Thaumastodinae

1. Tarsal formula 4-5–5; legs long and slender; antennal insertions situated near eyes ( Fig. 2A ); metaventrite short, not covering metacoxa ( Fig. 3A ); in freshwater environments; Oriental Region................................................................................................. Acontosceles Champion, 1924

– Tarsal formula 4-4-4; legs long and stout; antennal insertions situated near mandibles ( Fig. 2C, E ); metaventrite projecting posteriorly, covering metacoxa ( Fig. 3B ); in both fresh- and saltwater environments...................................................................................................................................... 2

2. Frons distinctly projecting anteriorly, narrow ( Fig. 2 E–F); male fore tarsi enlarged ( Fig. 3E ); in freshwater environments; Oriental Region............................................ Pseudeucinetus Heller, 1921

– Frons gently projecting anteriorly, wide ( Fig. 2 C–D); male fore tarsi normal; on rocky seashores ... ........................................................................................................................................................... 3

3. Antennae 7-segmented; antennal groove on gena absent; Neotropical Region................................... ..................................................................................................................... Martinius Spilman, 1959

– Antennae 11-segmented; antennal groove on gena present; Neotropical and Oriental Regions......... ......................................................................................................................... Mexico Spilman, 1972

Figures

Fig. 2. Head in frontal (A, C, E) and lateral (B, D, F) views. A, D. Acontosceles chujoi Yoshitomi & Satô, 2005. B, E. Mexico masamii (Satô, 1994). C, F. Pseudeucinetus zygops Heller, 1921.

Fig. 3. Metacoxal plates (A–B), hind tibiae (C–D) and male protarsus (E). A, C. Acontosceles chujoi Yoshitomi & Satô, 2005. B, D. Mexico taiwanus (Satô, 1994). E. Pseudeucinetus zygops Heller, 1921.