''Tegula pulligo'',

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contra ...

the dusky tegula, is a

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

of medium-sized sea snail with

gill 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 ar ...

s and an operculum, 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 mollusc in the family Tegulidae.Rosenberg, G. (2013). Tegula pulligo (Gmelin, 1791). Accessed through: World Register of Marine Species a
WoRMS - World Register of Marine Species - Tegula pulligo (Gmelin, 1791)
on 2013-12-30 This is an Eastern

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...

species.

Description

The size of the shell varies between 19 mm and 41 mm. The solid shell is deeply and widely umbilicate. It has a conical shape with an elevated

spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spires are ...

. Its color is dull purplish or brown, when worn often orange, obliquely streaked with white or unicolored. The seven

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane flo ...

s are flattened, the upper ones finely spirally striate and sometimes very obsoletely plicate. The remainder is smooth, obliquely finely striate. The base of the shell is flattened, slightly convex, obliquely streaked, concave and white around the

umbilicus Umbilicus may refer to: *The navel or belly button *Umbilicus (mollusc), a feature of gastropod, Nautilus and Ammonite shell anatomy * ''Umbilicus'' (plant), a genus of over ninety species of perennial flowering plants *Umbilicus urbis Romae The ...

. The body whorl is bluntly angled at the periphery. 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 very oblique, smaller than usual in this genus. The thin

columella Lucius Junius Moderatus Columella (; Arabic: , 4 – ) was a prominent writer on agriculture in the Roman Empire. His ' in twelve volumes has been completely preserved and forms an important source on Roman agriculture, together with the ...

is obtusely dentate, ending above in a white callus which partly covers the umbilicus. There is no spiral ridge within the umbilicus.Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
(described as ''Chlorostoma pulligo'')

Distribution

This species occurs in the Pacific Ocean from

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. It is usually found on kelp; once it falls to the bottom, it is easy prey for a number of predators, including sea stars, whelks, and octopus.

References

* Turgeon, D.D., et al. 1998. ''Common and scientific names of aquatic invertebrates of the United States and Canada''. American Fisheries Society Special Publication 26 page(s): 61

External links

* {{Authority control pulligo Gastropods described in 1791 Taxa named by Johann Friedrich Gmelin