''Pleurotomella ipara'' 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). . 39 ...
.
Description
The length of the shell attains 8.5 mm, its diameter 4.5 mm.
(Original description) The shell contains nine
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
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 minute, dark brown, polished and smooth. The second and third whorls of the protoconch are beautifully reticulated by oblique transverse lines in two directions. The remainder are waxy white, with the peculiar waxy lustre of abyssal shells. The shell is rather short-fusiform, the
spire subturreted by the concave ante-sutural band. The spiral
sculpture consists of about twenty-four flattened threads, with wider interspaces, before the band on 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 ...
. Only two or three of these threads are visible on the upper whorls. They pass over all the transverse ridges and are a little stronger over them. Next the suture are small, short, appressed plications, with a tendency to pair, and even to unite above, thus becoming staple-shaped. The ante-sutural band is excavated, smooth except for the terminations of the plicae, which cease near its posterior border. Near the anterior border the spiral threads begin, crossing sharply-projecting short oblique plications (thirteen on the body whorl) which disappear halfway from the perii) hery to the anterior end of the
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 ...
, and are somewhat angulated just in advance of the ante-sutural band. The notch is broad and deep. The outer
lip is thin and projecting. The columella is short, thin and twisted. The siphonal canal is short and broad.
Distribution
''P. ipara'' can be found in Caribbean waters, ranging from the coast of
Louisiana south to
Brazil.
[Tunnell, John W., Jr., Felder, Darryl L., & Earle, Sylvia A., eds. ''Gulf of Mexico Origin, Waters, and Biota, Volume 1: Biodiversity.'' Texas A&M University Press, 2009. 668.]
References
* Rosenberg, G., F. Moretzsohn, and E. F. García. 2009. ''Gastropoda (Mollusca) of the Gulf of Mexico'', Pp. 579–699 in Felder, D.L. and D.K. Camp (eds.), Gulf of Mexico–Origins, Waters, and Biota. Biodiversity. Texas A&M Press, College Station, Texas.
External links
*
Gastropods.com: ''Pleurotomella ipara''
{{DEFAULTSORT:Pleurotomella Ipara
ipara
Gastropods described in 1881