''Cryptodaphne gradata'' 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

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

Raphitomidae Raphitomidae is a family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea.Bouchet P. & Rocroi J.-P. (Ed.) (2005). "Classification and nomenclator of gastropod families". '' Malacologia'' 47(1-2). . 3 ...

Description

The length of the shell attains 10½ mm, its diameter 4¼ mm. (Original description) The white, fusiform shell is gradate and moderately strong. It contains 8

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 (the uppermost broken), of which 2 form a reddish-brown

protoconch A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called ...

, with convex whorls (their number probably will have been 4 of which 2 are wanting). The whorls are sculptured by curved riblets, crossed by oblique finer ones in the lower part, which is consequently finely reticulated. The subsequent whorls are convex, angular, gradate by a conspicuous excavation of the upper part, the lower part perpendicular. The spirals consist of a keel and a few, rather strong, slightly flattened lirae on the lower part, 4 in number on penultimate whorl and 2 narrow ones at the base of excavation, just above the keel The

body whorl The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the b ...

shows numerous stronger, flat lirae, eventually divided by a very fine groove, and some intermediate ones. The axial sculpture consists of numerous fine growth striae and curved riblets in the upper part of the excavation, less pronounced on the body whorl, not quite extending to the keel. The body whorl is convex, regularly attenuated towards the rather long

siphonal canal The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is ...

. The aperture is elongate, angular above, ending in a long, gutterlike siphonal canal below. The peristome is broken, probably with a moderately wide, shallow sinus. The columellar margin is concave, with a rather strong layer of enamel along the siphonal canal. Schepman, 1913. The prosobranchia of the Siboga expedition. Part IV -V - VI: Toxoglossa

Distribution

This species occurs in the Halmahera Sea, East Indonesia

References

External links

*
Gastropods.com: ''Cryptodaphne gradata''

Sysoev, A.V. (1996b) ''Deep-sea conoidean gastropods collected by the John Murray Expedition, 1933–34''. Bulletin of the Natural History Museum of London, Zoology, 62, 1–30. page(s): 22
{{DEFAULTSORT:Cryptodaphne Gradata gradata Gastropods described in 1913