Odostomia elsa
Encyclopedia
Odostomia elsa is a species
of sea snail
, a marine
gastropod mollusk in the family
Pyramidellidae
, the pyrams and their allies.
are very small and deeply immersed in the first of the succeeding turns. The six post-nuclear whorls are well rounded, with strongly concave summits, forming deeply channeled sutures. They are marked by slightly retractive lines of growth, and exceedingly fine, closely placed, wavy spiral striations. The periphery of the body whorl
is well rounded. The base of the shell is short, inflated andmoderately umbilicated. The aperture
is ovate. The posterior angle is obtuse. The columella is curved, slightly reflected, not reenforced by the base and provided with an oblique fold at some little distance anterior to its insertion. The parietal wall is covered by a thin callus.
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 yellowish white shell is ovate and umbilicated. Its length is 6.1 mm. The nuclear whorlsWhorl (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...
are very small and deeply immersed in the first of the succeeding turns. The six post-nuclear whorls are well rounded, with strongly concave summits, forming deeply channeled sutures. They are marked by slightly retractive lines of growth, and exceedingly fine, closely placed, wavy spiral striations. The periphery of the body whorl
Body whorl
Body whorl is part of the morphology of a coiled gastropod mollusk.- In gastropods :In gastropods, the body whorl, or last whorl, is the most recently-formed and largest whorl of a spiral or helical shell, terminating in the aperture...
is well rounded. The base of the shell is short, inflated andmoderately umbilicated. The 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 ovate. The posterior angle is obtuse. The columella is curved, slightly reflected, not reenforced by the base and provided with an oblique fold at some little distance anterior to its insertion. The parietal wall is covered by a thin callus.