The Natural History of the Enigmatic Neotropical Weevils Mecopelmus zeteki Blackman and Schedlarius mexicanus (Dugès) (Coleoptera: Curculionidae: Platypodinae?)

We review the classification, distribution, and biology of the enigmatic, rare Neotropical weevils Mecopelmus zeteki Blackman, 1944 and Schedlarius mexicanus (Dugès, 1885). Both taxa have been placed in multiple beetle families since being described. We compile the few previous records and add many new records for both species. Mecopelmus Blackman, 1944 has been collected from only four countries: Costa Rica, Panama, Peru (confirmed country record), and Brazil (new country record). Based on morphological and molecular data for M. zeteki, we conclude that, contrary to current classification, it is not a platypodine, but where it belongs remains unclear; consequently, we transfer Mecopelmus from Platypodinae to a previous subfamily of Curculionidae, Mecopelminae Thompson, 1992, status restored. New records for S. mexicanus show the species to occur in Mexico and probably all of Central America; Guatemala, El Salvador, and Costa Rica represent new country records. Known hosts for S. mexicanus are species of Bursera (Burseraceae) in dry tropical forests. Schedlarius mexicanus reproduces either pairwise or possibly in small harems, in long tunnels in dead wood, with larvae feeding on fungus-infected wood. Based on morphological data, limited sequence data, and phylogenetic analyses, this species is currently considered to be either a sister species of or basal within a broadly defined Platypodinae; consequently, we choose to retain it in Platypodinae. We conclude with a discussion of data gaps and uncertainties with respect to the classification and natural history of these two species.