Comparative morphology and key to Amydetinae genera, with description of three new firefly species (Coleoptera, Lampyridae)

Amydetinae is an exclusively Neotropical subfamily of fireflies, distributed among three genera: Illiger, 1807, McDermott, 1964, and Silveira & Mermudes, 2013. Here, we describe three new species of Amydetinae: two belonging to ( and ) and one to the previously monotypic ( ). All three species are known only from the Atlantic Forest in southeastern Brazil. Endoskeletal structures of and species are described and compared with those of for the first time. After studying the type material, Pic, 1942 is transferred to , generating , and Silveira & Mermudes, 2013 is placed as a junior synonym. We also redescribe Olivier, 1885 and compare it to other species of genus and to other amydetine taxa to identify potential new diagnostic traits for the Amydetinae and its constituting genera. We provide an updated diagnosis for , illustrations for all four species, and a distribution map for the three new species, as well as a key to adult males of the three amydetine genera, and an updated key to species based on males.