Abstract
The previously monotypic genus Motonerus Hansen, 1989 is revised and redefined. Seven new species are described: Motonerus andersoni FikáÖek & Short, sp. n. (Costa Rica, Panama), M. apterus FikáÖek & Short, sp. n., (Venezuela, Colombia), M. depressus FikáÖek & Short, sp. n. (Colombia), M. hanseni FikáÖek & Short, sp. n. (Costa Rica), M. nublado FikáÖek & Short, sp. n. (Venezuela), M. oosternoides FikáÖek & Short, sp. n. (Panama), and M. problematicus FikáÖek & Short, sp. n. (Costa Rica). Two additional new species from Bolivia are left undescribed pending the collection of males. New records are given for the previously described species, M. obscurus Hansen, which had been composite with respect to M. hanseni sp. n. Almost all collections of the genus are associated with cloud and montane forest litter. A key to the species of the genus is provided along with comments on the relationship of the genus with others in the tribe Megasternini. The unusual flightless condition found in M. apterus and M. oosternoides is discussed. The male genitalia and other key characters are illustrated.
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