Genus Trachyscelida Horn, 1893

Trachyscelida Horn, 1893: 107 (type species Agelastica bicolor LeConte, 1884, by monotypy). Racenisa Bechyné, 1958: 604 (type species Racenisa venezuelensis Bechyné, 1958, by original designation).

Remarks

This genus contains seven described species. They occur from the United States (Arizona) through much of South America. See Fig. 115 for a habitus illustration. See Bechyné (1958) for a key that includes most of the species. Agelastica bicolor LeConte, 1884, and Racenisa bicolor Bechyné, 1958, are both currently included in Trachyscelida . We here propose Trachyscelida dichroma nom. nov., as a replacement name for R. bicolor Bechyné, 1958 .

The Palearctic species Agelastica alni (Linnaeus, 1758), belonging to the tribe Hylaspini Chapuis, 1875, has been reported from eastern Canada and the northeastern United States, but this species is not thought to be established in North America (Riley et al. 2003). Since Agelastica Chevrolat, 1836 probably does not occur on the American continents, we have excluded this genus from the following key. However, if specimens were to be discovered, they would key to couplet 134, along with Trachyscelida, which shares a similar, broadly ovate body form. The two genera are easily distinguished by the pronotal color, that of Agelastica being concolorous with the dark elytra, while that of Trachyscelida is pale, strongly contrasting with the dark elytra.