Acrocirridae is a family of polychaete worms. Acrocirrids are detritivores (deposit feeders), catching falling particles with numerous long prostomial tentacles. There are eight known genera, and at least 21 described species and subspecies within the Acrocirridae family. The acrocirrids are primarily benthic (seabed-dwelling) animals, but at least two genera (Swima and Teuthidodrilus) appear to have evolved or adapted to a pelagic (free-swimming) habitat.