The genus Polycera Cuvier, 1817 (Nudibranchia: Polyceridae) in the eastern Pacific Ocean, with redescription of Polycera alabe Collier & Farmer, 1964 and description of a new species

Abstract

The nudibranch Polycera alabe Collier & Farmer, 1964 has been reported to be extremely variable in coloration. Some of this variation appears to be correlated with geographic range, with four regional colour forms having been recognized. However, the identity of P. alabe has been unclear because of its vague original description, based on only two specimens from Baja Califonia, Mexico, without any morphological or molecular study to date. Here we present a complete redescription, based on examination of the holotype and paratype, as well as study of new material from the type locality and vicinity. The description includes colour pictures, drawings of the reproductive system and electron micrographs of the radula and penis. New findings are reported, such as the presence of two well-developed cusps in the outer lateral teeth, a pair of digitiform and rather short salivary glands, and a penis with at least two different types of penial spines. We describe the reproductive system for the first time. Specimens similar to P. alabe in the external coloration, but with several external and internal differences such as the type of salivary glands and number of outermost teeth, are described as a new species, P. anae n. sp. from Panama and Costa Rica. These two species are compared with five other Polycera species known from the eastern Pacific.