''Cantharidus dilatatus'' 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.
[WoRMS (2012). ''Cantharidus dilatatus'' (G.B. Sowerby II, 1870). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=598217 on 2012-11-23]
Description
The shell grows to a length of 8 mm, its diameter also 8 mm.
The small, imperforate shell has a conical shape. It is spirally striated. Its
sculpture consistis of numerous fine and inconspicuous spiral striae, more distinct and a little further apart on the base.
Its colour is cinereous, pink, or pinkish-brown, usually with white markings near the suture or tessellated with white. Sometimes a broad dark-brown band encircling
the periphery of the
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, and one on the centre of the base. White zigzagbands are sometimes adorning the last 2 or 3 whorls. The epidermis is thin, slightly shining, easily worn off.
The
spire is conical, as high as the
aperture and a little convex. The
apex is acute. The
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 ...
is very small, consisting of 1½ smooth, slightly convex whorls. The six whorls are slightly convex. 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 ...
is obtusely angled at the periphery, and considerably expanded. The base of the shell is flat. The
sutures are linear, but little impressed. The aperture is subrotund, oblique, inside mostly highly bluish-reddish iridescent and finely lirate. The outer
lip is strengthened by an inner white callosity. The concave
columella is vertical. The inner lip is broadly expanded, covering the
umbilicus, and spreading as a broad white callosity over the
parietal wall.
Suter H. (1913-1915), Manual of New Zealand Mollusca; Wellington, N. Z. :J. Mackay, govt. printer,1913-1915
/ref>
Distribution
This marine species is endemic to New Zealand and occurs off the North, South, Stewart and Chatham Islands.
References
* Marshall, B.A. 1998: ''The New Zealand Recent species of Cantharidus Montfort, 1810 and Micrelenchus Finlay, 1926 (Mollusca: Gastropoda: Trochidae).'' Molluscan Research 19: 107-156 (p. 130)
* Powell A W B, ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979
* Miller M & Batt G, ''Reef and Beach Life of New Zealand'', William Collins (New Zealand) Ltd, Auckland, New Zealand 1973
External links
To World Register of Marine Species
*
{{Taxonbar, from=Q3141605
dilatatus
Gastropods described in 1870