Odostomia panamensis
Encyclopedia
Odostomia panamensis 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 milk-white, shining shell is small and measures 3.1 mm. It is heavy, elongate-ovate. Its 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...

 increase regularly in size. The whorls 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 small, almost completely obliquey immersed in the first of the succeeding volutions. The six whorls of the teleoconch are moderately and evenly rounded, of porcellanous texture, without any apparent marking,and separated by well marked sutures. 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 full and rounded. The base of the shell is inflated and well rounded. 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 small, decidedly rissoid, almost channeled anteriorly. The posterior angle is acute. The outer
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 lip decidedly curved backward anteriorly, very thick within but beveled to form a sharp edge. The columella is extremely short, somewhat reflected and connected posteriorly with the very strong parietal callus. This callus is fully as thick as the edge of the outer lip and connects with it at the posterior angle of the aperture, thus forming a complete periostracum. A prominent oblique fold is present on and a little anterior to the insertion of the columella.

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