Four new species of thelepodid polychaetes are reported from Taiwan, Streblosoma chiguensis sp. nov., Streblosoma wuchiensis sp. nov., Thelepus taiwanensis sp. nov., Thelepus longtongensis sp. nov. The family Thelepodidae, as well as the two genera Streblosoma and Thelepus, is reported for the first time from Taiwanese waters. A synoptic table, including number of branchial filaments on segments 2 to 4, the presence/absence of eyespots, number of pairs of notopodia, uncinial dental formula of anterior and posterior tori, and type locality, is provided for all species of Thelepus.
