''Ividella navisa'' 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
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* ...
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 Pyramidellidae, the pyrams and their allies. The species is one of a number within the genus ''
Chrysallida
''Chrysallida'' is a speciose genus of minute sea snails, pyramidellid gastropod mollusks or micromollusks in the family Pyramidellidae within the tribe Chrysallidini.Spencer, H.; Marshall. B. (2009). All Mollusca except Opisthobranchia. In: G ...
''.
[MolluscaBase eds. (2020). MolluscaBase. Ividella navisa (Dall & Bartsch, 1907). Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=397089 on 2020-11-25]
Distribution
This marine species occurs in the following locations:
*
Gulf of Mexico
* in the Pacific Ocean off the
Galapagos Islands.
Description
The shell is of medium size and grows to a length of 2.7 mm. It is strongly sculptured, subdiaphanous to milk-white. The nuclear
whorls
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 d ...
number at least two, and are obliquely a little more than half immersed. The five post-nuclear whorls are strongly shouldered and subtabulated. They have a strong, broad, spiral keel limiting the anterior edge of the shoulder and an acute raised keel on the middle of the whorls between the sutures, while a thir-d equally acute keel marks the periphery of the last whorl. Two other keels ornament the base, the anterior one of which is not quite as strong as its neighbor. The axial
sculpture consists of narrow, more or less lamellar, almost vertical ribs, which render the intersection with the spiral keels somewhat thickened, but not nodulose. These axial ribs extend over the periphery and base of 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 ...
to the umbilical region, gradually growing weaker as they approach this point. There are about 18 on the second and 20 upon the penultimate whorl. The spaces between the ribs and keels appear as concave quadrangular depressions. The
umbilicus is narrowly perforated. The
sutures are deeply channeled by the shouldered whorl. The
aperture is suboval. The posterior angle is decidedly obtuse. The
outer lip is thick, marked by 5 projections, corresponding to the 5 keels. The
columella is almost straight, strongly revolute with a conspicuous oblique fold near its insertion. The parietal wall is covered by a faint callus showing both basal keels, the anterior faint and just posterior to the insertion of the columella and the next on the middle of the wall.
William Healy Dall and Paul Bartsch , "A Monograph of West American Pyramidellid Mollusks" , Smithsonian Institution, 1909
(described as ''Folinella avisa'')
References
* Turgeon, D.; Quinn, J.F.; Bogan, A.E.; Coan, E.V.; Hochberg, F.G.; Lyons, W.G.; Mikkelsen, P.M.; Neves, R.J.; Roper, C.F.E.; Rosenberg, G.; Roth, B.; Scheltema, A.; Thompson, F.G.; Vecchione, M.; Williams, J.D. (1998). Common and scientific names of aquatic invertebrates from the United States and Canada: mollusks. 2nd ed. American Fisheries Society Special Publication, 26. American Fisheries Society: Bethesda, MD (USA). . IX, 526 + cd-rom pp.
* Landau B.M. & LaFollette P.I. (2015). The Pyramidellidae (Mollusca: Gastropoda) from the Miocene Cantaure Formation of Venezuela. Cainozoic Research. 15(1-2): 13-54.
External links
Dall W.H. & Bartsch P. 1907. ''The Pyramidellid mollusks of the Oregonian faunal area.'' Proceedings, United States National Museum, 33: 491-534, pl. 44-48
Gallery
File:Folinella navisa 001.png, Apertural view of ''Ividella navisa''
File:Folinella navisa delmontensis.png, Apertural view of ''Ividella navisa delmontensis''
External links
To World Register of Marine Species
{{Taxonbar, from1=Q61681717, from2=Q5114483
navisa
Gastropods described in 1907