|
Rissoa Hidasensis
''Rissoa'' is a genus of minute sea snails, marine gastropod mollusks or micromollusks in the family Rissoidae. The genus was first introduced by M. de Freminville for some small shells observed by M. Antoine Risso, a distinguished naturalist of Nice, France. They were described by M. Demarest in 1814 in the "New Bulletin of the Philomatic Society". Description The soft body of the snail is elongated and spiral. The somewhat prolonged mouth has a proboscis. The tentacles are awl-shaped with the eyes on a small prominence near the base. The foot is oval or elliptical. The species is phytophagous. The conical shell has an elongated spire with its apex nipple-shaped. The size of the shell varies between 1 mm and 8 mm. The whorls are generally convex-shaped with a distinct suture. The aperture is ovate, roundish or pear-shaped with its anterior end rounded, the posterior end acute and with the peristome complete. The thin and horny operculum is spirally marked ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
