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Vanitrochus Tragema
''Vanitrochus tragema'' is a species of sea snail, a marine (ocean), marine gastropod mollusk in the family (biology), family Trochidae, the top snails.Bouchet, P. (2012). ''Vanitrochus tragema'' (Melvill & Standen, 1896). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=547295 on 2012-11-23 Description The size of the shell varies between 1.8 mm and 4 mm. (Original description)This is a small conical chalky-white shell, colourless excepting for scattered transverse pink flames round the upper parts of the lower Whorl (mollusc), whorls just below the sutures. The shell is profoundly but narrowly umbilicate. The shell contains six whorls six, two being in the protoconch, slantingly angled in a gradate manner. The surface is closely acutely ribbed, the transverse decussations somewhat noticeable in the interstices, and these in some specimens give a crenulate appearance to the ribs themselves. The base is spira ... [...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] |
