Camponotus (Tanaemyrmex) sirindhornae sp. nov., a New Cave-dwelling Ant (Hymenoptera: Formicidae) from Thailand, with Its Ecological Notes

A newly cavernicolous ant species was discovered from cave environments and a man-made underground tunnel in Kanchanaburi Province, western Thailand based on worker and dealate queen. This represents the first record of the genus Camponotus nesting in subterranean habitats. The new species, described herein as Camponotus sirindhornae Jaitrong, Jantarit & Pitaktunsakul, sp. nov. is specialized to the subterranean lifestyle, displaying a set of troglobiotic traits i.e. reduced pigmentation, elongated antennae and appendages, and a slender head and body. It can be distinguished from its closely related congeners by a distinct combination of the following characters: 1) head of minor worker in full-face view, narrowed and prolonged behind eye, narrowest just in front of posterior margin, occipital carina forming distinct flange; 2) entire body (head, mesosoma and metasoma) reticulate with smooth and shiny interspaces; 3) head, mesosoma and petiole bright yellowish; 4) anterior half of each matasomal segments III–VI yellowish brown, while posterior half dark brown. The new species was observed prying on other cave-dwelling arthropods such as crickets, cockroaches, moths, and beetles. The ecology traits of this new species, along with its troglobiotic adaptation is also discussed.