''Nucella ostrina'', the northern striped dogwinkle, 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 ...

of sea snail, a marine gastropod

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

Muricidae Muricidae is a large and varied taxonomic family of small to large predatory sea snails, marine gastropod mollusks, commonly known as murex snails or rock snails. With about 1,600 living species, the Muricidae represent almost 10% of the Neoga ...

, the murex snails or rock snails. Other common names for this mollusk include emarginate dogwinkle, short-spired purple dogwinkle, striped dogwinkle, ribbed dogwinkle, emarginate whelk, ribbed rock whelk, rock thais, short-spired purple snail and rock whelk.

Description

This dogwinkle has a robust shell with three indistinct whorls. It can be in length, but a more typical length is or less; the

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An ...

is less than half the diameter of the shell and can be closed by a brown, horny operculum. The exterior of the shell is spirally ridged, often with heavy ridges alternating with more delicate ones. The heavy ridges may bear coarse nodules, but in more exposed locations these, and the ridges themselves, may be partially smoothed. The ridges tend to be pale in color and the furrows between them dark, typically brown, gray, black, orange or yellow. The interior of the shell is purple.

Distribution and habitat

''M. ostrina'' is native to the northeastern Pacific Ocean. Its range extends down the western coast of North America from the

Aleutian Islands The Aleutian Islands (; ; ale, Unangam Tanangin,”Land of the Aleuts", possibly from Chukchi ''aliat'', "island"), also called the Aleut Islands or Aleutic Islands and known before 1867 as the Catherine Archipelago, are a chain of 14 large v ...

, Alaska, to

Cayucos, California Cayucos (Spanish for "Canoe") is an unincorporated coastal town in San Luis Obispo County, California, along California State Route 1 between Cambria to the north and Morro Bay to the south. The population was 2,505 at the 2020 census, down fr ...

. It is found in the intertidal zone on rocky coasts, often in the vicinity of mussel beds, and particularly in wave-exposed positions.

Ecology

Like the other members of its family, this dogwinkle is a

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

. Each individual has its own food preferences, but the population as a whole feeds predominantly on mussels and barnacles (''Balanus glandula''), but sometimes on periwinkles ('' Littorina sitkana'' and '' Littorina planaxis''), or limpets ('' Collisella scabra''). The bay mussel (''Mytilus trossulus'') is usually preferred as prey over the California mussel (''Mytilus californianus''). Having selected its prey, the dogwinkle drills into the shell with its radula, injects digestive

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...

s which liquefy the tissues, and sucks out the contents. The dogwinkle is itself eaten by the purple sea star (''Pisaster ochraceus'') and the red rock crab (''Cancer productus''). It lays its eggs in clusters of stalked capsules, known as "sea oats", which are attached to rocks high up in the intertidal zone. Although there are around 550 eggs in each capsule, most of the eggs are infertile and are consumed by the developing juveniles, 10 to 20 of which hatch from the capsule after three or four months, without an intermediate larval stage.

References

{{DEFAULTSORT:Nucella Ostrina Muricidae Gastropods described in 1852 Molluscs of the Pacific Ocean