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Oxystele Merula
''Oxystele merula'' is a species of sea snail, a marine gastropod mollusk in the family (biology), family Trochidae, the top snails.Bouchet, P. (2013). Oxystele merula (Dillwyn, 1817). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=739283 on 12 February 2014 Description The height of the shell varies between 27 mm and 40 mm, its diameter between 35 mm and 41 mm. The rather depressed conoidal shell is imperforate. Its color is lusterless purplish-black. The conical Spire (mollusc), spire has an eroded yellowish Apex (mollusc), apex. The following Whorl (mollusc), whorl is spirally striate. The last two whorls are smooth. The six whorls are convex. The Suture (anatomy), sutures are distinct. The body whorl is not carinated at the periphery, rather flattened on the base, and usually slightly eroded in front of the Aperture (mollusc), aperture. The large aperture is oblique. The outer Lip (gastropod), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Whorl
The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the body whorl, or last whorl, is the most recently formed and largest whorl (or revolution) of a spiral or helical shell, terminating in the aperture. It is called the "body whorl" because most of the body of the soft parts of the animal fits into this whorl. The proportional size of the body whorl in gastropod shells differs greatly according to the actual shell morphology. For shells in which the rate of whorl expansion of each revolution around the axis is very high, the aperture and the body whorl are large, and the shell tends to be low spired. The shell of the abalone is a good example of this kind of shell. The opposite tendency can sometimes create a high spire with very little whorl increase per revolution. In these instances, e.g. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
