External slope or top on coral reef.
Up to 2 inches (5.1 cm).
"External anatomy: Flatworm with irregular and variable color pattern characterized mainly by a cream background mottled with orange, and pink and purple-red dots concentrated medially forming an elongated blotch. The margin consists of purple and pink irregular spots and dots that are more concentrated on the tentacles making the tips a little darker. The ventral side is light violet. Pseudotentacles formed by simple folds of the anterior margin with few marginal eyes. Cerebral cluster made of about 30 eyespots. Presence of a broad folded pharynx. Internal anatomy: The male reproductive system consists of unbranched vas deferens, an elongated seminal vesicle connected to a short and coiled ejaculatory duct, a round prostatic vesicle, and a small stylet housed in a deep antrum. The female system has a deep and tubular female antrum with curved cement pouches and a short vagina directed backwards and surrounded by the cement gland."
Benthic, diurnals, because of its aposematic colors, it has no fear to crawl around to feed.
Pseudoceros goslineri feeds on various colonial ascidians.