Odostomia culta
Encyclopedia
Odostomia culta is a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of sea snail
Sea snail
Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....

, a marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 gastropod mollusk in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Pyramidellidae
Pyramidellidae
Pyramidellidae, common name the pyram family, or pyramid shells, is a voluminous taxonomic family of mostly small and minute ectoparasitic sea snails, marine heterobranch gastropod molluscs or micromolluscs....

, the pyrams and their allies.

Description

The regularly conic, yellowish white shell is umbilicated. It measures 4 mm. The whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...

 of the protoconch
Protoconch
A protoconch is an embryonic or larval shell of some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod...

 are apparently planorboid, very obliquely, almost completely, immersed in the first of the later whorls, only a portion of the last volution being visible. The six whorls of the teleoconch are rather high between the sutures, slightly rounded (almost flattened), and subtabulately shouldered at the summits. They are marked by fine lines of growth and very many subequal, wavy, closely spaced striations. The whorls are somewhat angulated at the periphery and the summit of the succeeding whorls falls a little anterior to the periphery, which gives the sutures a decidedly channeled effect. The base of the ody whorl]$ is large, rather prolonged, well rounded. It is marked by spiral striations which are equally as abundant as those between the sutures but somewhat stronger. The suboval aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....

 is moderately large, and somewhat effuse anteriorly. The posterior angle is obtuse. The outer lip
Lip (gastropod)
In the shell of a gastropod mollusk , the margin of the aperture is called the lip or the peristome. In other words, this is a term used to describe part of gastropod shell anatomy....

 is thin. The columella is slender, curved, reflected partly over the moderately large
umbilicus and provided with a strong, acute, oblique fold near its insertion. The parietal wall is covered by a thin callus.

External links

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