''Hypselodoris festiva'', the festive sea slug, is a common

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of colourful

sea slug Sea slug is a common name for some Marine biology, marine invertebrates with varying levels of resemblance to terrestrial Slug, slugs. Most creatures known as sea slugs are gastropods, i.e. they are Sea snail, sea snails (marine gastropod moll ...

or dorid

nudibranch Nudibranchs () are a group of soft-bodied marine gastropod molluscs, belonging to the order Nudibranchia, that shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have b ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Chromodorididae Chromodorididae, or chromodorids, are a taxonomic family of colourful sea slugs; dorid nudibranchs, marine gastropod mollusks in the superfamily Doridoidea. “Chromodorid nudibranchs are among the most gorgeously coloured of all animals.� ...

. It eats sponges.

Distribution

This nudibranch was described from Tsushima,

Korea Strait The Korea Strait is a strait, sea passage in East Asia between the Korean Peninsula and Japan. It connects the East China Sea, the Yellow Sea and the Sea of Japan in the northwest Pacific Ocean. The strait is split by Tsushima Island into two par ...

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

. It is found in Japan,

Hong Kong Hong Kong)., Legally Hong Kong, China in international treaties and organizations. is a special administrative region of China. With 7.5 million residents in a territory, Hong Kong is the fourth most densely populated region in the wor ...

, and also

Korea Korea is a peninsular region in East Asia consisting of the Korean Peninsula, Jeju Island, and smaller islands. Since the end of World War II in 1945, it has been politically Division of Korea, divided at or near the 38th parallel north, 3 ...

.Rudman, W.B., 1999 (July 1
''Hypselodoris festiva'' (A.Adams, 1861).
nSea Slug Forum. Australian Museum, Sydney.

Description

''Hypselodoris festiva'' has a dark blue mantle with a central longitudinal yellow line, which may be broken, yellow spots and a yellow margin. The yellow spots may join up to form two more lines and in large individuals extra yellow spots develop between them. The

rhinophore A rhinophore is one of a pair of Chemoreceptor, chemosensory club-shaped, rod-shaped or ear-like structures which are the most prominent part of the external head anatomy in sea slugs, Marine (ocean), marine gastropod opisthobranch mollusks suc ...

s have blue shafts and red lamellae on the clubs. The gill leaves are translucent white with a single red line on the outer edge and red lines on the inner edges.Behrens, D. W., 1999
''Hypselodoris festiva''
The Slug Site, Michael D. Miller 1999. It is preyed upon by '' Gymnodoris rubropapulosa''.

References

{{Taxonbar, from=Q3787991 Chromodorididae Gastropods described in 1861