''Isanda'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

s, marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

s in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Trochidae The Trochidae, common name top-snails or top-shells, are a family of various sized sea snails, marine gastropod molluscs in the subclass Vetigastropoda. This family is commonly known as the top-snails because in many species the shell resembles ...

, the top snails.

Description

The compact shell of species in this genus has an orbicular-conoidal shape and is porcellanous and polished. The subquadrate

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

is longer than wide, The inner lip is straight, forming an angle with the outer lip. The umbilicus is open (not covered by a callous deposit) and perspective. The margin is crenulated. The multispiral operculum is corneous. The interior has a very thin nacreous layer.

Species

Species within the genus ''Isanda'' include: * '' Isanda coronata'' A. Adams, 1854 * '' Isanda holdsworthana'' H. Nevill & G. Nevill, 1871 * '' Isanda murrea'' (Reeve, 1848) ;Species brought into synonymy: * ''Isanda crenellifera'' A. Adams, 1862: synonym of '' Microthyca crenellifera'' (A. Adams, 1862) * ''Isanda lepida'' A. Adams, 1853: synonym of '' Isanda coronata'' A. Adams, 1854 * ''Isanda pulchella'' A. Adams, 1855: synonym of '' Ethaliella pulchella'' (A. Adams, 1855)

References

Arthur Adams, ''A monograph on Isanda, a new genus of Trochidae allied to Umbonium''; Proceedings of the Zoological Society of London pt. 21-23 (1853-1855)
* Williams S.T., Karube S. & Ozawa T. (2008) ''Molecular systematics of Vetigastropoda: Trochidae, Turbinidae and Trochoidea redefined''. Zoologica Scripta 37: 483–506. {{Taxonbar, from=Q6078815 Trochidae Gastropod genera