Abstract
BACKGROUND: Phylum Phoronida currently contains two genera, Phoronis Wright, 1856 and Phoronopsis Gilchrist, 1907, with approximately thirteen speices. Phoronida is distributed worldwide, ranging from northern Europe to southern New Zealand and also from intertidal to 400 m depths. From Japanese waters, four species of Phoronis have been reported, viz. Phoronisijimai Oka, 1897, Phoronisaustralis Haswell, 1883, Phoronispsammophila Cori, 1889 and Phoronisemigi Hirose et al., 2014. NEW INFORMATION: We describe the morphology of Phoronopsiscalifornica Hilton, 1930, based on five specimens collected at a sandy-mud habitat in Nago Bay and Oura Bay, Okinawa, Japan. We examined the internal anatomy by serial paraffin sections. We also examined the genetic distance of Japanese specimens from the other phoronid sequences in GenBank. This is the first record of Phoronopsis from Japanese waters and the fifth species record of phoronids in addition to the previously recorded four species of Phoronis.