Eopachylopus Reichardt, 1926

Lackner, Tomáš, 2010, Review of the Palaearctic genera of Saprininae (Coleoptera: Histeridae), Acta Entomologica Musei Nationalis Pragae (suppl.) 50, pp. 1-254 : 95

Eopachylopus Reichardt, 1926

Eopachylopus Reichardt, 1926: 14 (as a subgenus of Neopachylopus Reichardt, 1926 ). Eopachylopus: REICHARDT (1941) : 157, 327; KRYZHANOVSKIJ & REICHARDT (1976): 111, 241; MAZUR (1984): 108; ÔHARA (1994): 214, 262; MAZUR (1997): 266; MAZUR (2004): 91.

Type species: Pachylopus ripae Lewis, 1885 , original designation.

Diagnosis. Cuticle not metallic, usually black with red elytral maculae; frontal stria carinate; supraorbital, postorbital striae complete; frontal disc smooth; pronotal disc almost smooth, marginal pronotal stria complete, pronotal foveae absent, pronotal hypomeron glabrous; elytral disc smooth, marginal elytral stria complete, apical elytral stria complete, dorsal elytral striae abbreviated, sutural stria well-impressed, basally abbreviated. Propygidium with sparse round punctures and microsculpture; pygidium almost smooth. Prosternal process strongly compressed, knife-like, pre-apical foveae absent; carinal striae present only on prosternal apophysis; lateral prosternal striae very shortened, convergent anteriorly, apically connected attaining about middle of prosternal process; discs of meso- and metaventrite smooth; lateral disc of metaventrite and metepisternum with dense setiferous punctures. Posterior surface of protibia with several rows of denticles; mesotibia and metatibia slightly thickened and dilated apically; anteriorly with at least four dense rows of denticles; claws of apical tarsomere long, thin; metafemora thickened.

Differential diagnosis. By the compressed prosternal process Eopachylopus is somewhat similar to the genus Chivaenius differing from it by numerous characters: absent pronotal as well as elytral punctation (present in Chivaenius ), the shape of tibiae, much shorter ventral vestiture (considerably longer in Chivaenius ) as well as the frequent presence of red elytral maculae (absent in Chivaenius ).

Biology. Eopachylopus is a littoral taxon, occurring under wrack where it probably preys on wrack-associated dipteran larvae (Ôhara, pers. comm. 2006).

Distribution. This is a monotypic genus with Eopachylopus ripae , as its only representative. This species is distributed in Japan and in Russian Far East. Recently recorded also from Hong Kong ( DE ROUGEMONT 2000); the identity of these specimens needs to be confirmed by further studies.

Species examined. Eopachylopus ripae ( Lewis, 1885) .

Discussion. This taxon is defined by several putative synapomorphies, e.g. very shortened lateral prosternal striae or absent pre-apical foveae and knife-like prosternal process. However, its phylogenetic validity should be tested in the future, focusing especially on its relationship with Nearctic as well as Middle-Eastern representatives of the genus Neopachylopus . Eopachylopus was originally described as a subgenus of Neopachylopus .