Phyllidia coelestis

Images taken at Lembeh, Indonesia

Phyllidia coelestis is broad and oval in shape. The basic colours of P. coelestis are blue to grey-blue, black and yellow. The notum has three black longitudinal bands; two of these bands run laterally, each on the outside of two, mediolateral, blue-grey ridges which have tubercles capped in yellow. The ridges, which may be interrupted in some specimens, originate anteriorly behind each rhinophore and converge posteriorly in the region of the anus. Two tall, narrow, gold-capped rhinotubercles are present, one immediately behind each rhinophore. The rhinotubercles are separate from the two ridges. Two to four isolated, large, yellow capped tubercles arise from the median black band; however, these are never joined as a midline ridge. There are always two isolated tubercles in the midline, onc immediately anterior to, and the other immediately posterior to, the rhinophores. The rhinophores are yellow in colour and each clavus possesses 19-26 lamellae. Around the mantle margin is a broad blue-grey band with small tubercles, the larger ones of which may be yellow capped. Sometimes, meanderings of black encroach into this blue-grey margin. The foot is grey and has no distinctive markings on its sole