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Fossarina Petterdi
''Fossarina petterdi'' is a species of very small sea snail, a marine gastropod mollusc or micromollusk in the family Trochidae, the top snails.Marshall, B. (2013). Fossarina petterdi Crosse, 1870. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=719228 on 2014-03-03 Description The shell grows to a length of 4 mm. The shell is narrowly umbilicated, faintly spirally striate, with hardly visible longitudinal striae. It is dark purplish black, with a few irregular white markings. The three whorls are convex. The 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 b ... is large and rounded. The umbilical region is white. The interior is greenish black, showing the external white markings. The thin, horny opercu ... [...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] |
