A new stalked species of Polycarpa (Tunicata : Ascidiacea) from deeper waters of the tropical Western Pacific and in situ observations on sympatric species

A new species of a stalked ascidian (genus Polycarpa, family Styelidae) is described from living and preserved material. Living specimens of the new and some sympatric species were observed and photographed in situ and specimens of the former were collected by the manned submersible "JAGO" at depths between 200 and 277 m off Sangihe Island between Sulawesi (Indonesia) and the Philippines. Specimens display a number of adaptations known previously from a range of ascidian taxa recorded from deeper waters, including a stalk from the anterior end of the body, the loss of ciliated pharyngeal perforations and wide atrial apertures exposing extensive areas of the branchial sac.