Iolaea eucosmia
Encyclopedia
Iolaea eucosmia is a species
of sea snail
, a marine
gastropod mollusk in the family
Pyramidellidae
, the pyrams and their allies.
are deeply obliquely immersed in the first of the succeeding: turns, above which only the tilted edge of the last one project. The six post-nuclear whorls are somewhat contracted at the periphery and very strongly slopingly shouldered at the summit. They are marked by three strong lamellar keels between the sutures, of which the middle one is a little nearer to its anterior neighbor than to the posterior, the latter being about as far from the summit as it is from the median keel. The deep channels between the keels and the shoulders are crossed bv slender axial riblets which have a protractive slant on the shoulder and are decidedly
retractive in the channels. The periphery of the body whorl
is marked by a keel a little weaker than those between the sutures. The base of the shell is short, well rounded, narrowly umbilicated. It is marked by three spiral cords and a slender raised thread about the umbilicus. The channels bounding the
peripheral cord and those of the base are crossed by riblets as on the spire
. The aperture
is large. The posterior angle is obtuse. The outer lip
is rendered angulated by the keels, thus showing the external sculpture within. The columella is slender, very strongly curved, slightly reflected and provided with a weak fold at its insertion. The parietal wall is covered with a weak callus.
, California, to Point Abreojos, Lower California.
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 elongate-conic shell is, subdiaphanous to milk-white. It measures 2.5 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 deeply obliquely immersed in the first of the succeeding: turns, above which only the tilted edge of the last one project. The six post-nuclear whorls are somewhat contracted at the periphery and very strongly slopingly shouldered at the summit. They are marked by three strong lamellar keels between the sutures, of which the middle one is a little nearer to its anterior neighbor than to the posterior, the latter being about as far from the summit as it is from the median keel. The deep channels between the keels and the shoulders are crossed bv slender axial riblets which have a protractive slant on the shoulder and are decidedly
retractive in the channels. 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 marked by a keel a little weaker than those between the sutures. The base of the shell is short, well rounded, narrowly umbilicated. It is marked by three spiral cords and a slender raised thread about the umbilicus. The channels bounding the
peripheral cord and those of the base are crossed by riblets as on the spire
Spire (mollusc)
A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...
. 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 large. 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 rendered angulated by the keels, thus showing the external sculpture within. The columella is slender, very strongly curved, slightly reflected and provided with a weak fold at its insertion. The parietal wall is covered with a weak callus.
Distribution
This species occurs in the Pacific Ocean from San PedroSan Pedro Bay (California)
San Pedro Bay is an inlet on the Pacific Ocean coast of southern California, United States. It is the site of the Port of Los Angeles and the Port of Long Beach, which together form the fifth-busiest port facility in the world and easily the busiest in the Western Hemisphere...
, California, to Point Abreojos, Lower California.