The insular birddrop or

San Clemente Island San Clemente Island (Tongva: ''Kinkipar''; Spanish: ''Isla de San Clemente'') is the southernmost of the Channel Islands of California. It is owned and operated by the United States Navy, and is a part of Los Angeles County. It is administered b ...

blunt-top snail,

scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''Vertigo clementina'', 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 small, air-breathing

land snail A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial gastropod mollusks that have shells (those without shells are known as ...

, a

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

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

Vertiginidae Vertiginidae, common name the whorl snails, is a family of minute, air-breathing land snails, terrestrial pulmonate gastropod molluscs or micromollusks in the superfamily Pupilloidea. Distribution The distribution of the Vertiginidae is in the ...

.''Sterkia clementina''.

NatureServe NatureServe, Inc. is a non-profit organization based in Arlington County, Virginia, US, that provides proprietary wildlife conservation-related data, tools, and services to private and government clients, partner organizations, and the public. Nat ...

Explorer, accessed 1 August 2010. (Incorrectly placed within Chondrinidae in the 2006 IUCN Red List.) MolluscaBase eds. (2023). MolluscaBase. Vertigo clementina. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=1431022 on 2023-02-08

Description

(Original description) The shell is very minute, narrowly perforate and cylindrical. It is pale horn colored, transparent, with rather obtuse

apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics), a teenaged super villainess in the Marvel Universe * Ape-X, a super-intelligent ape in the Squadron Supreme universe *Apex ...

. The shell contains 5½

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 floral ...

s, regularly increasing and moderately rounded. They contain a rather deep suture. The shell is smooth, with few microscopic striae, somewhat shining. The

body whorl The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the b ...

occupies rather more than two-fifths of the length of the shell and is somewhat ascending to 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 opt ...

, with a slight, revolving impression on the middle of its last half, ending at the auricle. There is a very slight, flat, crest-elevation near the margin, only in the lower part. The aperture is lateral, scarcely oblique, subovate with the palatal margin slightly flattened, the upper part of same somewhat sinuous. The peristome is a little expanded with a slightly thickened outer

lip The lips are the visible body part at the mouth of many animals, including humans. Lips are soft, movable, and serve as the opening for food intake and in the articulation of sound and speech. Human lips are a tactile sensory organ, and can be ...

just at the margin. The shell contains six white lamellae: two on the apertural wall, the apertural, typical, and a rather long supra-apertural, ending in a callus at the upper termination of the palatal margin. The horizontal columellar margin is typical. The basal is very small, nodule-like and deep seated. The two palatals are typical, the inferior a little longer. Sterki, V. (1890). A new Pupa. The Nautilus. 4(4): 44, pl. 1, fig. 4
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Distribution

This species is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the State of

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, U.S.A. The survival of this species is "near threatened".

References

External links

Vanatta, E. G. (1916). Bifidaria clementina oldroydae, n. var. The Nautilus. 30(4): 48
{{Taxonbar, from=Q946788

clementina Clementina may refer to: Literature *Clementine literature, or Clementina, a 2nd-century religious romance * ''Clementina'' (play), a 1771 tragedy by Hugh Kelly *Clementina (character), a fictional character in the ''Jeeves'' series Other uses *C ...

Fauna of the United States Gastropods described in 1890