''Monodonta perplexa'' 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 perplexa'' Pilsbry, 1889. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=546931 on 2012-11-23 This genus consists of two subspecies: * ''Monodonta perplexa boninensis'' Asakura & Nishimura, 1987 * ''Monodonta perplexa perplexa'' Pilsbry, 1889

Description

The height of the shell attains 8.5 mm, its diameter 10 mm. The imperforate, oblique shell has a depressed-conoid shape. It is light green, radiately flamulate above with wide zigzag dark green stripes, more narrowly striped below, encircled about the middle with a well-defined lighter zone. The entire surface is polished, and marked with numerous slightly impressed light-colored spiral lines. The acute, conic spire is very short. The sutures are more impressed than usual in this group. 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 are quite convex, the upper ones ruddy or purplish, the last very large, slightly compressed just below the suture, and gently descending anteriorly. The very large aperture is very oblique. The acute outer lip is thin, pearly and iridescent, and, apparently lirate within. The columella is extremely oblique. Its inner edge is concave, distinctly toothed or hooked below, bearing a shallow groove parallel with the edge, from the place of the umbilicus downward. The white columellar area is very wide.Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
/ref>

Distribution

This marine species occurs off Taiwan 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

Barcode of Life (1 barcode)

Biodiversity Heritage Library (4 publications)

Encyclopedia of Life

GenBank (2 nucleotides; 0 proteins)

World Register of Marine Species
* {{Taxonbar, from=Q6901536 perplexa Gastropods described in 1889