Jorunna funebris, common name the dotted nudibranch, is a large species of sea lung, a dorid nudibranch, a shell-less marine gastropod mollusc in the family Discodoridae .
This species was described from Sri Lanka. It is widespread in the Indo-Pacific region from the Red Sea and the Indian Ocean along the East African coast to Australia and New Caledonia.
Nudibranchs are a group of soft-bodied, marine gastropod molluscs which shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have been given colourful nicknames to match, such as “Clown”, “Marigold”, “Splendid”, “Dancer” and “Dragon”. Currently, about 2,300 valid species of nudibranchs are known.
Nudibranchs are often casually called sea slugs, as they are a family of Opistobranchs (sea slugs), with the phylum Mollusca (molluscs) but many sea slugs belong to several taxonomic group groups which are not closely related to nudibranchs. A number of these other sea slugs, such as the photosynthetic Sacoglossa and the colourful Aglajidae, are often confused with nudibranchs.
Nudibranchs occur in seas worldwide, including in the tropics and the Southern Ocean.
Nudibranchs live at virtually all depths of salt water, from the intertidal zone to depths well over 700 m. The greatest diversity of nudibranchs is seen in warm, shallow reefs, although a new nudibranch species was discovered at a depth near 2,500 m.
Nudibranchs are benthic animals, found crawling over the substrate. The only exceptions to this are the neustonic Glaucus nudibranchs, which float upside down just under the ocean’s surface, and the pelagic nudibranchs Cephalopyge trematoides, which swims in the water column and Phylliroe bucephalum.
(extract from Wikipedia)