Undressing Lophodoris danielsseni (Friele & Hansen, 1878) (Nudibranchia: Goniodorididae)

Lophodoris G. O. Sars, 1878 is a small genus of goniodoridid nudibranchs that includes only two species: the type species, Lophodoris danielsseni (Friele & Hansen, 1876), and Lophodoris scala Er. Marcus & Ev. Marcus, 1970. Sars (1878) erected Lophodoris in a footnote, without comment. Forty-four years later, Odhner (1922) finally described the type species and defined the diagnostic characteristics of Lophodoris. Lophodoris danielsseni is well differentiated among Goniodorididae species by a dorsal crest and jagged notum margin supported by spicules. However, the description of this species is still incomplete since information on the reproductive system or spicules pattern is not known. In the present work, we study freshly collected specimens of Lophodoris danielsseni (Friele & Hansen, 1876) from near the type locality. Morphological analyses are performed using micro-computed tomography as well as by dissections. We include the first scanning electron microscope photographs of the radula, labial cuticle, and penial spines. Moreover, we carry out a preliminary phylogenetic analysis using barcoding and including five out of eight genera belonging to the family Goniodorididae. Result shows for the first time its phylogenetic relationship within the family, separating each genus included. However, further species must be sequenced to clarify the evolutionary relationship among Goniodorididae species and genera.