Asteronotus mimeticus Gosliner & Valdes, 2002
Many sea slugs boast magnificent flamboyant colors, while other like this critter simply doo not. This ugly little bugger gets its name from mimicking the undersurface of sponges such as Phyllospongia lamellosa and Carteriosponga sp. I'll never forget following Terry Gosliner on a dive and wondering what the heck he was doing folding over these flat paperlike sponges, examining their underside. Now I know. The question is - How did Terry and Jim Anderson find these critters in the first place?
Of the six described species of Asteronotus, A. mimeticus is most similar to the recently described Red Sea species, Asteronotus markaensis Donohoo & Gosliner2020. Although coloration is similar between the two species, molecular phylogeny shows strong genetic divergence separating the them.
SAMANTHA A. DONOHOO & TERRENCE M. GOSLINER. 2020. A tale of two genera: the revival of Hoplodoris (Nudibranchia: Discodorididae) with the description of new species of Hoplodoris and Asteronotus 2020. Zootaxa 4890 (1): 001-037.