''Discurria insessa'', common name the seaweed limpet, 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 snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a true

limpet Limpets are a group of aquatic snails that exhibit a conical shell shape (patelliform) and a strong, muscular foot. Limpets are members of the class Gastropoda, but are polyphyletic, meaning the various groups called "limpets" descended indep ...

, 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 ...

mollusk 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 e ...

in the family

Lottiidae Lottiidae is a family of sea snails, specifically true limpets, marine gastropod mollusks in the superfamily Lottioidea and the clade Patellogastropoda (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Subfamilies 20 ...

Description

The size of the shell varies between 10 mm and 38 mm.

Distribution

This marine species occurs from South

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...

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

Ecology

''D. insessa'' is believed to live only on ''

Egregia menziesii ''Egregia menziesii'' is a species of kelp known commonly as feather boa kelp. It is the only species in the monotypic genus ''Egregia''. It is native to the coastline of western North America from Alaska to Baja California, where it is a com ...

'' (feather boa kelp). Young limpets seem to orient randomly on the stipe but adults are almost always oriented longitudinally along the stipe. ''D. insessa'' feed both on

epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

s and on the ''Egregia'' itself. ''D. insessa'' spawns mainly in spring and summer. There is high mortality during the winter—the largest individuals are usually not more than 1 year old. Larvae settle preferentially on large, crowded, post-reproductive ''Egregia'' and on fronds which already have adults. They grow fastest if they settle on scars made by older limpets. This species runs away quickly if it contacts a

seastar Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea (). Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish ...

such as ''

Pisaster ochraceus ''Pisaster ochraceus'', generally known as the purple sea star, ochre sea star, or ochre starfish, is a common seastar found among the waters of the Pacific Ocean. Identified as a keystone species, ''P. ochraceus'' is considered an important indi ...

''.Discurria insessa
at

Walla Walla University Walla Walla University is a private Adventist university in College Place, Washington. The university has five campuses throughout the Pacific Northwest. It was founded in 1892 and is affiliated with the Seventh-day Adventist Church. The uni ...

References

* Nakano T. & Ozawa T. (2007). ''Worldwide phylogeography of limpets of the order Patellogastropoda: molecular, morphological and paleontological evidence''. Journal of Molluscan Studies 73(1): 79–99

External links

Lottiidae Gastropods described in 1842 {{Lottiidae-stub