Resumen

Forty-nine new species of Neotropical Exosternini are described in this work, representing the newly recognized Phelister blairi species group, within the large, heterogeneous taxon Phelister. Eight previously described species are also assigned to this group. Relationships within are indicated with several informal subgroups: P. blairi subgroup: (P. blairi Hinton, 1935, P. erwinisp. nov., P. fimbriatussp. nov., P. stellanssp. nov., P. sparsussp. nov., P. pretiosussp. nov., P. trigonisternus Marseul, 1889, P. globosussp. nov., P. serratussp. nov., P. geminussp. nov., P. paranasp. nov., P. asperatussp. nov., P. uniformissp. nov., P. miscellussp. nov., P. inbiosp. nov., P. sculpturatus Schmidt, 1893, P. tunkisp. nov., P. praedatoris Reichensperger, 1939, P. ifficussp. nov., P. genierisp. nov., P. marginatussp. nov., P. vazdemelloisp. nov., P. dilatatussp. nov., P. spectabilissp. nov., P. pervagatussp. nov.); P. amazoniae subgroup: (P. morbidussp. nov., P. annulatussp. nov., P. sphaericussp. nov., P. geijskesi Kanaar, 1997, P. fraternussp. nov., P. conjunctussp. nov., P. chabooaesp. nov., P. striatinotum Wenzel & Dybas, 1941, P. notandus Schmidt, 1893, P. amazoniae (Lewis, 1898) comb. nov., P. arcuatussp. nov.); P. gregarius subgroup: (P. gregariussp. nov., P. praecisussp. nov., P. rudissp. nov., P. incongruenssp. nov., P. congruenssp. nov., P. praesignissp. nov.); P. umens subgroup: (P. umenssp. nov., P. almeidaesp. nov., P. chicomendesisp. nov., P. microdenssp. nov., P. matatlanticasp. nov.); P. curvipes subgroup: (P. curvipessp. nov., P. vilavelhasp. nov.); P. rio subgroup: (P. riosp. nov., P. semotussp. nov., P. uncinatussp. nov., P. inscriptussp. nov.); incertae sedis – unplaced to subgroup: (P. incertussp. nov., P. okeefeisp. nov., P. blairoidessp. nov., P. piranasp. nov.). Lectotypes are designated for the following species: P. trigonisternus Marseul, P. sculpturatus Schmidt, P. praedatoris Reichensperger, P. notandus Schmidt, and Discoscelis amazoniae Lewis. Preliminary phylogenetic analyses of the broader Neotropical Exosternini do not support the monophyly of the P. blairi group, nor of all of these subgroups, but the majority do fall within one large clade (which is potentially paraphyletic with respect to some other Neotropical exosternine genera). More work on the phylogeny and taxonomy of this diverse fauna is needed.