Description and phylogeny of a new Neotropical genus of Acalyptini associated with cyclanth inflorescences (Coleoptera: Curculionidae: Curculioninae)

Acalyptini Thomson is a tribe of curculionine weevils with pantropical distribution. Most of the 270 constituent species, grouped in nearly 40 genera, are intricately associated with the reproductive organs of Araceae, Arecaceae and Cyclanthaceae. Recent systematic work has allowed us to recognize natural lineages within the tribe, and has furthermore fostered a better understanding of the varied evolutionary trajectories of acalyptine/host associations. One such lineage is the Staminodeina which contains species associated with the ephemeral modified stamens (staminodes) of Cyclanthaceae inflorescences. This subtribe includes the genus Staminodeus Franz, with seven described species, as well as its putative sister group, a genus complex of small weevils with a relatively short and tumescent rostrum. Here we present morphological and natural history information pertinent to 13 new species in the latter genus, including representatives from Brazil, Colombia, Costa Rica, Ecuador, Honduras, Panama, Peru and Venezuela. Based on a phylogenetic analysis of at least 20 terminals and more than 50 characters, we discuss the likely mechanisms of diversification, host specificity, distribution, and reproductive strategies of the ingroup species, and contrast them with the evolutionary history of Staminodeus.