Mourning Dorid

Overview

The Mourning Dorid (Jorunna funebris) is a striking sea slug known for its distinctive white body patterned with black rings or spots. As a dorid nudibranch, it lacks a shell and features a feathery gill plume on its back, which, along with its sensory rhinophores, can be retracted for protection.

Appearance

This species is easily recognized by its "fuzzy" or velvety texture, caused by thousands of tiny, spiculate structures called caryophyllidia that cover its mantle. The black markings on its body are actually clusters of these dark-pigmented papillae. While the pattern is variable—ranging from small, sparse spots to large, coalescing rings—the rhinophores are typically black-tipped, and the gills often feature dark edges. Juveniles often display simple black spots that expand into rings as the animal matures.

Distribution & habitat

The Mourning Dorid is widely distributed throughout the tropical Indo-Pacific, ranging from the Red Sea and the East African coast to Australia, Japan, and Hawaii. It is commonly found in shallow reef environments, including reef flats, lagoons, and rocky coasts, typically at depths between 1 and 50 meters. They are often spotted moving across sandy substrates or coral rubble while searching for food.

Feeding

This nudibranch is a specialized carnivore that feeds exclusively on sponges, particularly those within the genus Xestospongia. Its presence in a specific area is often closely tied to the availability of its preferred sponge prey. Due to these highly specific dietary requirements, it is not suitable for aquarium environments.