''Diaulula sandiegensis'' 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 ...

, a 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 shell-less

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

Discodorididae Discodorididae is a taxonomic family of sea slugs, specifically dorid nudibranchs, marine gastropod mollusks in the superfamily Doridoidea.Bouchet, P. (2011). Discodorididae. Accessed through: World Register of Marine Species at http://www.marine ...

. The specific epithet ''sandiegensis'' means: "of

San Diego San Diego ( , ; ) is a city on the Pacific Ocean coast of Southern California located immediately adjacent to the Mexico–United States border. With a 2020 population of 1,386,932, it is the List of United States cities by population, eigh ...

", the

Southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most po ...

city.

Distribution

This dorid nudibranch occurs in the eastern Pacific, from

Barkley Sound , image = Fishing boat in the Broken Group Islands.jpg , image_size = 260px , alt = , caption = Barkley Sound , image_bathymetry = , alt_bathymetry = , caption_bathymetry = , locat ...

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

, Mexico. It has been confused with '' Diaulula boreopacifica'' which has a more northerly range and also occurs in

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

and

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.Lindsay, T., Kelly, J., Chichvarkhin, A., Craig, S., Kajihara, H., Mackie, J & Valdés, A. (2016). ''Changing spots: pseudocryptic speciation in the North Pacific dorid nudibranch ''Diaulula sandiegensis'' (Cooper, 1862) (Gastropoda: Heterobranchia).'' Journal of Molluscan Studies doi:10.1093/mollus/eyw026

Description

This nudibranch grows to about 100 mm (4") in length. The background color can be white or any shade of yellow to a yellowish brown, and it has characteristic markings consisting of a few brown rings or irregular spots. Specimens with more numerous spots are ''Diaulula odonoghuei''.Kocian, J., 2006 (Apr 21
''Diaulula sandiegensis'' from Puget Sound.
essage in/nowiki> Sea Slug Forum. Australian Museum, Sydney.

Life habits

This species feeds on

sponges Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through ...

References

{{Taxonbar, from=Q3167364 Discodorididae Gastropods described in 1862 Taxa named by James Graham Cooper