Trapania tartanella

Trapania tartanella is a translucent white nudibranch adorned with yellow-orange markings. Its rhinophores, gills, and processes are tipped with yellow pigment that transitions to orange at the tips. This species can be easily distinguished from Trapania hispalensis, which has uniform yellow markings. Originally described from the Mediterranean, it is found along the Atlantic coast, stretching from Portugal to Pembrokeshire in South Wales. This nudibranch typically inhabits demersal environments and is often associated with sponges where it can find its food source. Feeding primarily on Entoprocta, which grow on sponges, Trapania tartanella plays a role in the ecosystem by contributing to the balance of marine life. The species exhibits simultaneous hermaphroditism, allowing individuals to mate with one another, where they engage in a unique mating behavior involving the use of their penises. Eggs are laid on substrates, where they develop into a planktonic larval stage before maturing into adults. Divers encountering Trapania tartanella may observe it moving slowly across the substrate, blending in with its surroundings due to its cryptic coloration. The conservation status of this species is not evaluated, indicating that there is currently no formal assessment of its population trends or threats.