''Aeolidia loui'' 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 ...

s, an aeolid nudibranch, 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

Aeolidiidae Aeolidiidae, a family of aeolid nudibranchs, are a family of sea slugs, shell-less marine gastropod molluscs.Bouchet, P. (2014)''Aeolidiidae'' Gray, 1827.Accessed through: World Register of Marine Species on 2014-10-24 Most, or perhaps all, mem ...

. It has been regarded as the same species as the NE Atlantic ''

Aeolidia papillosa ''Aeolidia papillosa'', known as the common grey sea slug, is a species of nudibranch in the family Aeolidiidae.Gofas, S''Aeolidia papillosa''.In: MolluscaBase (2017). Accessed through: World Register of Marine Species (WoRMS), 26 July 2017. Dis ...

'' but is now known to be a distinct species. Common names include shaggy mouse nudibranch, and shag-rug nudibranch.McDonald, G
''Aeolidia papillosa'' (Linnaeus, 1761).
Intertidal Invertebrates of the Monterey Bay Area, California. UC Santa Cruz.

Distribution

This nudibranch species was described from the intertidal region at Duxbury Reef, Marin County, California. It is known from

Cape Arago Cape Arago State Park is a state park in the U.S. state of Oregon, administered by the Oregon Parks and Recreation Department. Cape Arago is north of Bandon and 15 miles southwest of Coos Bay on Cape Arago Highway in Coos County. History In 15 ...

, Oregon, to

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 ...

, California, USA on the Pacific Coast of

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

Description

''Aeolidia loui'' can be easily identified by its large number of flattened cerata on its body except for a triangular area that extends from the rhinophores to the mid dorsum. The cerata vary in color from grey to white and sometimes pink, orange, or green hues, depending on the species of anemone it has been feeding on. The rhinophores are warty in living animals.

Ecology

Feeding habits

''Aeolidia loui'' feeds almost entirely on various species of anemones. However, due to limited mobility of nudibranchs and often highly concentrated distribution of prey, individual nudibranchs may concentrate on an individual species of prey during their lifetime.Greenwood, Paul G.. "Adaptable Defense: A Nudibranch Mucus Inhibits Nematocyst Discharge and Changes With Prey Type Biological Bulletin 206. 2 (2004), 113-120, https://www.jstor.org/stable/1543542. (accessed April 21, 2010) These nudibranchs feed mostly feed on the tentacles of the sea anemone.

Protozoan symbiosis

''Aeolidia loui'' has been shown to harbor the symbiotic organisms of sea anemones, which may increase nutrient production.McFarland, F. K.. "Photosynthesis and Retention of Zooxanthellae and Zoochlorellae within the Aeolid Nudibranch Aeolidia papillosa. Biological Bulletin 184. 2 (1993), 223-229, https://www.jstor.org/stable/1542230. (accessed May 10, 2010) Zooxanthellae and zoochlorellae are endosymbiotic organisms found in many sea animals that fix carbon through the process of

photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored i ...

while contributing greatly to their host's growth. Research has shown that these symbionts continue to perform high levels of photosynthesis and remain in ''Aeolidia loui''’s cerata for as much as eleven days, translocating a significant amount of fixed carbon to the nudibranch's bodily tissues.

Chemical manipulation of prey

A unique phenomenon displayed by ''Aeolidia loui'' has been studied, revealing an ability to prevent the species of anemone being preyed upon from discharging its nematocysts. ''A. loui'' appears to have the ability to adapt to the species of anemone currently being consumed. Though the mechanism is not yet fully understood, the chemical composition of the nudibranch's mucus changes, and does not trigger a discharge of nematocysts in the sea anemone. This effect can even be true for two different species of anemone if the nudibranch has been feeding on both species within a short time period. However, eventually this ability wears off if the nudibranch changes its dietary source for too long.

References

{{Taxonbar, from=Q25349757 Aeolidiidae Gastropods described in 2016