The first troglobiotic species of the family Pudeoniscidae (Crustacea, Isopoda, Oniscidea), with descriptions of a new genus and two new species.

Approximately 170 species of terrestrial isopods are known from Brazil, but only 12 are considered troglobionts. The family Pudeoniscidae comprises four species in two genera, Brasiloniscus and Pudeoniscus. After the examination of material collected in caves in the state of Bahia, a new genus and two new species have been recognized, Iansaoniscus iraquara gen. et sp. n. from Buraco do Cão cave, Iraquara, and Iansaoniscus georginae gen. et sp. n. from Borboletas cave, Paripiranga. The new genus and new species are placed in Pudeoniscidae on the basis of some morphological characteristics, such as antennal flagellum with second and third articles divided by a slender suture, epimera of pereonite 1 with dorsolateral furrow reduced or absent, and shape of uropods. The Brazilian subterranean environments are now under potential threat because of recent legislation for cave exploitation, and the knowledge of the subterranean biodiversity of the country is thus of primary importance for its effective conservation.