Taxonomic revision and phylogenetic relationships of the bee genus Parapsaenythia Friese (Hymenoptera, Apidae, Protandrenini), with biogeographic inferences for the South American Chacoan Subregion

The bee genus Parapsaenythia Friese (Apidae, Protandrenini) is restricted to South America and characterized by the strongly punctate integument and hairy eyes. In the present work, the species of Parapsaenythia are revised, with seven species recognized, of which three are described as new: P. carinulata sp.n. (Argentina, Brazil, Paraguay), P. inornata Moure (Brazil), P. lanata sp.n. (Brazil), P. paspali (Schrottky) (Argentina, Brazil, Paraguay), P. puncticutis (Vachal) (Argentina, Bolivia), P. scutellaris sp.n. (Argentina, Bolivia, Brazil, Paraguay) and P. serripes (Ducke) (Argentina, Brazil). Lectotypes are designated for Psaenythia (Parapsaenythia) argentina Friese, Anthrenoides paspali Schrottky and Parapsaenythia paraguayae Brethes. Floral records, distribution maps, illustrations and an identification key are provided. The cladistic analysis of 11 terminal species (all species of Parapsaenythia plus four outgroup species), based on 45 characters of external morphology and male terminalia, produced a single most parsimonious tree. Parapsaenythia was recovered as monophyletic, with the relationships among its species as follows: (P. inornata (P. carinulata sp.n. (P. lanata sp.n. (P. scutellaris sp.n. (P. serripes, P. paspali, P. puncticutis))))). Based on these relationships plus the available distributional data, a cladistic biogeographic analysis was performed, and area cladograms for the Chacoan subregion are presented and discussed.