Tomarus Erichson, 1847

Ratcliffe, Brett C. & Cave, Ronald D., 2010, The Dynastinae (Coleoptera: Scarabaeidae) of the Cayman Islands (West Indies), with descriptions of Tomarus adoceteus, new species (Pentodontini) and Caymania nitidissima, new genus and species (Phileurini), Insecta Mundi 2010 (139), pp. 1-15 : 6-7

Tomarus Erichson, 1847

The genus Tomarus contains 27 species ( Endrödi 1985; Dechambre and Lumaret 1985; Escalona and Joly 2006). Species in the genus occur from north-central United States south to Argentina. Eleven species are found exclusively in South America, and another ten species are found exclusively in North and Central America. Seven species are shared

between Central and South America. Three spe-

cies are recorded from the islands of the West

Indies.

Species of Tomarus can be recognized by an

attenuate clypeus that is bidentate and relatively

narrow at the apex, mandibles usually visible from

above and with two or three lateral teeth,

frontoclypeal region with two tubercles or a trans-

verse carina, and pronotum with or without an

apical tubercle and subapical fovea.

Life history information for most of the spe-

cies is sparse. Adults are nocturnal and attracted

to lights. In general, larvae are found in soil rich

in organic matter where they feed, sometimes on

the roots of living plants.

Considerable reliance must be placed on the

form of the male parameres for identification. The

parameres are usually extremely fragile (almost

parchment-like) and break or tear easily. Great

care should be taken when extracting the

parameres from the abdomen for study.

The genus Tomarus was previously referred

to in the literature as Ligyrus Burmeister , but

Ligyrus was placed in junior synonymy with

Tomarus by Ratcliffe (2002, 2003).