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Megasurcula Howei
''Megasurcula howei'' is an extinct species of sea snail, a marine gastropod mollusk in the family (biology), family Pseudomelatomidae, the turrids and allies. Description The length of the shell attains 36 mm, its diameter 23.6 mm. This high-spired, biconic species differs from ''Megasurcula condonana'' (Anderson and Martin, 1914) by having a smoothly conic Spire (mollusc), spire and relatively narrower body whorl. When the body whorl angulation is used as a point of reference, in non-apertural view, the upper cone of ''M. howei'' is relatively higher than the lower cone, whereas the reverse is true in specimens of the stout-shelled ''M. condonana''. Further differences are the more acute sutural angle and the concave profile of ''M. condonana''. It is closely related to † ''Megasurcula guayasensis'' of the Miocene in Ecuador, but differs by being less slender, a bit taller and less finely noded. [...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] |
