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Raphitoma Bracteata
''Raphitoma bracteata'' is a species of sea snail, a marine gastropod Mollusc, mollusk in the family (biology), family Raphitomidae. Description The shell reaches a length of 13 mm, and a diameter of 6 mm. The subfusiform, turreted, white shell has a pointed Spire (mollusc), spire. It contains 6 Whorl (album), whorls, of which only 1½ whorl in the protoconch. The subsequent whorls are convex with axial, close and elevated ribs and elevated, decurrent, parallel threads, forming nodules on the cross-points. The suture is impressed. The body whorl is ventrose. The subovate Aperture (mollusc), aperture measures half the length of the shell. The Columella (gastropod), columella is slightly twisted at its base. The open siphonal canal is very short. The outer lip is rounded, very convex, incrassate inwards and ending in a V-shape sinus at its top. Distribution The holotype of this marine species was found off Tunisia. References * Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Moll ... [...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] |
