Red Sea Opisthobranchia 6: Phyllidiidae and their paradorid mimic: new species and new records (Heterobranchia, Nudibranchia, Doridina)

With the complexity of the family Phyllidiidae and the problems of identification in the Indo-West Pacific, the story of the Red Sea species continues to unfold. One new species and one new record are added to the Red Sea fauna, both belonging to the genus Phyllidiella. Phyllidiella amphitritesp. nov. is described from a single specimen from the northern Red Sea and clearly differs from all species of Phyllidiella in having pale yellow pigment on the tubercles. Phyllidiella zeylanica is newly recorded from the Red Sea with five specimen records and several photographed individuals; other than this, it has a western Indian Ocean distribution. Phyllidia schupporum was collected for the first time since its original description; because its distribution is now extended to the Persian Gulf, it is no longer considered endemic to the Red Sea. The distribution of the Red Sea endemic Phyllidia dautzenbergi is extended northwards to Hurghada, Egypt. A small specimen of the endemic Phyllidiopsis sinaiensis was found at 214–237 m depth just at the mouth of the Red Sea, which is a bathymetrical range extension from its previous shallow coral reef records. The identifications of other species are revisited. A new species of Paradoris is described as Paradoris hypocritasp. nov., differing from the well-known but localised West Pacific P. liturata which also resembles a phyllidiid. This new species was recorded many years ago by published photographs, and it is relatively common in the Red Sea, evidenced by several specimens and additional photographs. It is described herein, and is considered a Red Sea endemic, differing from both the unnamed Indian Ocean species and the named Pacific species.