''Hypselodoris roo'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

sea slug Sea slug is a common name for some marine invertebrates with varying levels of resemblance to terrestrial slugs. Most creatures known as sea slugs are gastropods, i.e. they are sea snails (marine gastropod mollusks) that over evolutionary t ...

or dorid

nudibranch 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 matc ...

, a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

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.” ...

.MolluscaBase (2018)
''Hypselodoris roo'' Gosliner & Johnson, 2018.
Accessed through: World Register of Marine Species on 2018-09-25.

Distribution

This nudibranch was described from Mainit Bubbles, Calumpan Peninsula, Mabini,

Batangas Batangas, officially the Province of Batangas ( tl, Lalawigan ng Batangas ), is a province in the Philippines located in the Calabarzon region on Luzon. Its capital is the city of Batangas, and is bordered by the provinces of Cavite and La ...

Luzon Luzon (; ) is the largest and most populous island in the Philippines. Located in the northern portion of the Philippines archipelago, it is the economic and political center of the nation, being home to the country's capital city, Manila, as ...

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

, . It is also reported from

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

Description

''Hypselodoris roo'' has frequently been mistaken for '' Hypselodoris kanga''. It has a white body covered with large yellow spots and smaller blue-black spots. The dark blue spots at the edge of the mantle have a diffuse halo of bright blue around them. The

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

have lines on the outer edges which are orange-red and a flattened area between with opaque white spots. The

rhinophores A rhinophore is one of a pair of chemosensory club-shaped, rod-shaped or ear-like structures which are the most prominent part of the external head anatomy in sea slugs, marine gastropod opisthobranch mollusks such as the nudibranchs, sea hares ...

have bright red clubs and red bases. ''

Hypselodoris confetti ''Hypselodoris confetti'' is a species of sea slug or dorid nudibranch, a marine gastropod mollusc in the family Chromodorididae. Distribution This nudibranch was described from Siar Island, Madang, Papua New Guinea, . It is reported from Indone ...

'' is almost identical to this species, but with yellow spots on the outer gill faces which are edged with lines which grade from blue-purple at the base to red at the tips. This species can reach a total length of at least 45 mm.

References

{{Taxonbar, from=Q60524325 Chromodorididae Gastropods described in 2018 Molluscs of the Pacific Ocean