Corotoca (Coleoptera: Staphylinidae) beetles are known for their close integration in the nests of the termite Constrictotermes cyphergaster (Termitidae: Nasutitermitinae). Although this relationship is regarded as ancient, many details are still obscure, such as their reproduction and the processes that lead to the dispersal of new beetles. We observed the use of termite foraging trails by Staphylinidae females to deposit and disperse their larvae. We recorded the deposition of larvae of C. melantho, C. fontesi, and C. sp. n. on the dorsal surfaces of termite host workers. The workers continue to follow the foraging trail until the newborn larvae freed themselves and fell into the leaf litter, subsequently burrowing into the ground. Information regarding the life stages of those Staphylinidae larvae outside the termite nest is important to understanding their full lifecycle as those taxa have strong relationships with the nest environment but also require dispersal strategies.

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 only two genera with species confirmed as viviparous in the family. Some other cases are only supposition. Also, it is presented information and discussion 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 it was 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 fitnees in relation to a hypothetical condition in which the adult is the dispersive agent.

This study deals with the global estimation of the species of Corotocini (Aleocharinae) based on taxonomic description rates. We estimate the maximum number of possible extant species by maximum likelihood using the Michaelis-Menten model fitted into a non-linear regression. Although the studies regarding Corotocini are majorly taxonomic descriptions, the results suggest that there are many yet undescribed species, We also highlight that the basic knowledge regarding these organisms ecology is fairly obscure. Since the discovery of the first organism living in association with termites, the taxonomic effort hasn't been constant along the years, and although our results suggest that many species lie undiscovered, the lack of specialized professionals can compromise the actual knowledge regarding their biodiversity. Besides that, we comment on the future of this field and the lack of specimens from various locations.

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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 (C. 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.