''Monodonta neritoides'' is a species of

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk in the family Trochidae, the top snails.Bouchet, P. (2012). ''Monodonta neritoides'' (Philippi, 1849). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=546930 on 2012-11-23

Description

The height of the shell attains 16 mm. The imperforate shell has a semiglobose shape and is very oblique. The shell is smooth, black, painted with numerous white zigzag lines. The five

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral ...

s rapidly widen.. The spire is retuse. The aperture is semiovate. The thin lip is duplicated and coarsely crenate. The flat columella is grooved by a parallel sulcus, terminating in an acute tooth below. The shell is very similar to a '' Nerita'' on account of its semiglobose form, very obtuse spire, flat base and rapidly widening whorls. The uppermost whorls are flat, and spirally striate. The penultimate whorl is convex. The last whorl is completely smooth, obliquely descending, flatly depressed above, almost concave. The aperture is almost exactly like that of ''

Monodonta canalifera ''Monodonta canalifera'', common name the canal monodont, is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails. Description The size of the shell varies between 18 mm and 30 mm. The shell is si ...

''. The outer lip is on its outer part, inside the edge lined with mother-of-pearl, visibly furrowed.. On this part borders a white porcellanous coat, underneath standing out like a rib, on the base cut by two furrows. The throat is nacreous all around. The columella is compressed, flat, arcuate, produced into a sharp tooth below, and outwardly with a furrow parallel with its free margin. The color is black, with narrow white dense zig-zag curved streaks. The spire is pure black. There are forms with more elevated whorls, departing a little from the usual form.Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
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Distribution

This marine species occurs off Taiwan, Korea and

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

References

External links

To Biodiversity Heritage Library (15 publications)

To Encyclopedia of Life

To USNM Invertebrate Zoology Mollusca Collection

To World Register of Marine Species
* {{Taxonbar, from=Q6901537 neritoides Gastropods described in 1849