Dinomus Brême, 1842

Genus Dinomus Brême, 1842

Dinomus Brême, 1842: 24 .

Type species: Dinomus perforatus Brême , by monotypy.

Doyenellus , Nabozhenko & Steiner, 2021: 567. Type species: Helops cisteloides Germar. syn. nov.

Neohelops Dajoz, 2001: 356 . Type species: Neohelops texanus Dajoz. syn. nov.

Nautes Pascoe, 1866: 475 . Type species: Nautes fervidus Pascoe. syn. nov.

Tarpela Bates, 1870: 272 . Type species: Tarpela brownii Bates. syn. nov.

Stenotrichus LeConte, 1862: 239 . Type species: Amphidora rufipes LeConte. syn. nov.

Biomorphus Motschulsky, 1872: 38 . Type species: Biomorphus tuberculatus Motschulsky (= Amphidora attenuata LeConte ). syn. nov.

Coscinoptilix Allard, 1876: 15 . Type species: Coscinoptilix gracilicornis Allard. syn. nov.

Lamperos Allard, 1876: 4 . Type species: Helops micans Fabricius. syn. nov.

Diagnosis. Body variable, 4-20 mm long, shining and submetallic to matte and piceus, often shining brownish black. Eyes reniform, facets small, longitudinally compressed in dorsal view, with or without marginal groove; gena without longitudinal groove beneath eye; antennae with 11 antennomeres, variable, terminal antennomere rounded or elongate, always asymmetrical. Femora without spines; tarsi often with yellow silky setae beneath, but ranging from plantar surface lined with stout black setae to large flattened tomentose pads. Epipleuron ending near apex of fourth ventrite, not attaining elytral apex. Male aedeagus of the catomoid form, with parameres much shorter than phallobase, with apical two thirds covered in short anteriorly directed spinose setae.

Remarks. The synonymies presented for this genus follow from the reassessment of the genera presented above. We believe that flight has been lost multiple times (and can even be sexually dimorphic such as in Dinomus arizonensis ) in this lineage and that corresponding differences in body convexity, elytral shape, pro- and mesosternal morphology are a result. Moreover, our expanded unified genus concept, which follows that proposed by Horn (1870), more truly aligns with available phylogenetic data and makes this group readily diagnosable.

Table 1 View TABLE 1 outlines the proposed nomenclatural changes in New World Helopini along with the current name and species examined. Full nomenclatural and bibliographic data can be found in Bousquet et al. (2018) and Bouchard et al. (2021). These nomenclatural changes necessitate renaming one species:

Dinomus horni Aalbu & Johnston nom. nov. for Helops perforatus Horn, 1880: 153 . ( Fig. 13 View FIGURE 13 ) Distribution: USA: Texas. Secondary homonym of Dinomus perforatus Brême, 1842:24 .