Abstract
Freshwater clams were collected in the State of Roraima from the Uraricoera River and its igarapés near
Maracßa Island, the Parimé River at Pedra Pintada, and the Branco River at Boa Vista. Six hydriid species, two
mycetopodids, and one sphaeriid were identified. The holotype of Andontites schomburgianus (SOWERBY,
1870) was rediscovered in the British Museum (Natural History). This species and Castalia schombergiana
SOWERBY, 1869, are reported for the first time from the Amazon Basin. Diplodon obsolescens F. BAKER,
1914, had previously been found only where the type specimen was collected, so its known range has been
extended. Habitat preferences and the distribution of each species are provided.
