Abstract Fonsechellus Silvestri and Oecidiophilus Silvestri consist of two Neotropical genera of termitophilous rove beetles, which have been poorly characterized due to the scarcity of material for studies. Herein, based on material collected in the seventies and housed in the Museu de Zoologia da Universidade de São Paulo, two new species associated with Atlantitermes guarinim Fontes and Diversitermes sp., are described and illustrated: Fonsechellus heterosetosus sp. nov. and Oecidiophilus cleidecostae sp. nov., respectively. The latter represents the first record of the genus to Brazil. Also, Fonsechellus fragilis and F. fontesi are redescribed, and a key for species identification is provided for the genus. The condition of the membranous wings of Fonsechellus is addressed and discussed, and the definition of both genera is expanded.

Abstract Viviparity is characterized by the retention of fertilized eggs in reproductive tract of the female. This condition is very common in vertebrates, but relatively rare in invertebrates, including insects. The present work presents a review on viviparity in Staphylinidae, with special attention on genus Corotoca Schiødte, 1853. The genus is composed by six termitophilous species with neotropical distribution, and together with Spirachtha Schiødte, 1853 are the only to genera with species confirmed as viviparous in the family. Also, information and discussion are presented on the life cycle of Corotoca species based on dissection of females in laboratory and field observations. During the dissection of females of four species of Corotoca we observed that each female carries three eggs at the same time. The embryos present asynchronous development: when one is located at apex of abdomen, the other two are at IV segment, on abdomen curvature. These observations are complementary with those obtained in field observation, when the female deposits a larva outside the nest, on the foraging trail of termite Constrictotermes cyphergaster (Silvestri, 1901). The strategy of Corotoca species focused on the immature as dispersing agent is derived and probably favor the fitness in relation to a hypothetical condition in which the adult is the dispersive agent.

Abstract Rove beetles belonging to the genus Corotoca (Staphylinidae: Aleocharinae) are termitophiles exclusively found in nests of Constrictotermes (Isoptera: Termitidae). We observed the reproductive behavior of Corotoca melantho and C. fontesi during host (Constrictotermes cyphergaster) foraging events. The reproductive behaviors of both species are similar. The variables collected for analysis were distance traveled, the time of larval deposition, nest return time, and locomotion speed. The fact that the female stops in the middle of the foraging trail to deposit the larva leads to a discussion of how its physiological or voluntary mechanisms function to determine the correct stopping time and the importance of speed when returning to the nest as a strategy to avoid predation. This study provides new information concerning the life cycle of Corotoca spp., although complete understanding of host-termitophile relationships, their evolutionary history, and the significance of viviparity will require additional studies.