The paleoichnofauna in bones of Brazilian Quaternary cave deposits and the proposition of two new ichnotaxa

Abstract

The Quaternary vertebrate paleontology of the Brazilian Intertropical Region is well-known, but there are only a few publications on bone ichnology. In this paper, we analyzed trace fossils in 23 bones of the Gruna das Três Cobras, Complexo Suíço, and F3 caves, which are located in Bahia and Rio Grande do Norte states, in the Brazilian Intertropical Region. We discovered gnaw marks assigned to Machichnus and bite marks attributed to Nihilichnus, as well as insect modifications referring to single (Cuniculichnus, Gunnellichnus, Karethraichnus, and Osteocallis) and multiple behaviors (Munitusichnus, and Taotieichnus). Additionally, we proposed the new ichnospecies Nihilichnus sulcatus n. isp. (bite mark) and Cuniculichnus cascudoi n. isp. (insect feeding mark). Regarding the predation/scavenger marks, Protocyon troglodytes was the probable primary modification agent, but some traces may also be attributed to Smilodon populator and Caiman latirostris. Cuniculichnus, Karethraichnus, Munitusichnus, and Osteocallis are attributed to dermestids, whereas termites probably produced Gunnelichnus and Taotieichnus.