Menestho felix
Encyclopedia
Menestho felix is a species
of sea snail
, a marine
gastropod mollusk in the family
Pyramidellidae
, the pyrams and their allies.
of the protoconch
are small, almost completely obliquely immersed, only part of the last rounded volution is visible above the first of the later whorls. The 5½ whorls of the teleoconch are somewhat inflated, well rounded and moderately shouldered. They are marked by strong. equally developed. spiral keels which are separated by subequal, deep, rounded sulci. The latter are somewhat broader than the keels and crossed by many, very slender raised axial threads. Three keels are present upon the first and second, on the third a fourth keel appears partly at the suture, but the greater part of it is covered up by the summit of the succeeding volution. The penultimate whorl has four keels, the posterior one of which marks the summit and is a little wider than the rest and somewhat flattened. The periphery of the body whorl
is marked by a sulcus. The base of the shell is well rounded and attenuated. It is ornamented like the spaces between the sutures, having six spiral keels. These keels, as well as the sulci, gradually diminish in breadth from the periphery to the umbilical region. The aperture
is oval. The outer lip
is thin, showing the external sculpture
within. The columella is rather heavy, somewhat curved, backed up by the attenuated base and provided with a strong oblique fold at 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 broadly elongate-conic shell is turrited and subdiaphanous.It measures 2.6 mm. The 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...
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 obliquely immersed, only part of the last rounded volution is visible above the first of the later whorls. The 5½ whorls of the teleoconch are somewhat inflated, well rounded and moderately shouldered. They are marked by strong. equally developed. spiral keels which are separated by subequal, deep, rounded sulci. The latter are somewhat broader than the keels and crossed by many, very slender raised axial threads. Three keels are present upon the first and second, on the third a fourth keel appears partly at the suture, but the greater part of it is covered up by the summit of the succeeding volution. The penultimate whorl has four keels, the posterior one of which marks the summit and is a little wider than the rest and somewhat flattened. 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 sulcus. The base of the shell is well rounded and attenuated. It is ornamented like the spaces between the sutures, having six spiral keels. These keels, as well as the sulci, gradually diminish in breadth from the periphery to the umbilical region. 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 oval. 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, showing the external sculpture
Sculpture (mollusc)
The sculpture of a mollusc shell is the three-dimensional ornamentation on the outer surface, as distinct from the basic shape of the shell itself or colouration. Sculpture may be concave as well as convex. Sometimes it has microscopic detail. Sculpture refers to the calcareous outer layer, not the...
within. The columella is rather heavy, somewhat curved, backed up by the attenuated base and provided with a strong oblique fold at its insertion. The parietal wall is covered by a thin callus.