Pyramidella is the
type genus of the family Pyramidellidae.[2]
Nomenclature
The generic name Pyramidella Lamarck, 1799, has been validated under the Plenary Powers of the
ICZN , Opinion 386 (1955). The name Obeliscus Anonymus, 1797 [= Obeliscus Gray, 1847] has also been used for this genus, whereas the name Pyramidella was used for the genus now known as Otopleura Fischer, 1885.[1]
General description
The shell has an elongate-conic shape, slightly striated. The many
whorls of the
teleoconch are usually inflated and regularly increasing. They are longitudinally ribbed or smooth. The semioval
aperture is entire, widened at its base and rounded in front. .The
columella has one to three folds. The sharp
outer lip is entire, inferiorly sub-perforated and often plicate within with three transverse folds. The shell is usually larger than in Turbonilla. The thin
operculum is horny, ovate, elongated, with very fine elements and oblique folds
and folds oblique. The shell lacks an
epidermis.[3][4][5]
The shells are generally quite small, of an elegant form, elongated, marked with more or less deep spots. The general color of the body of these mollusca, is of a dull white. The operculum only, and the edge of the mantle are yellowish.[5]
The animal has a head surmounted by broad, rather long tentacles, formed like a pointed horn, and open on the side. The mouth is situated in a flattened, wide, dilated, and quite deeply two-lobed muzzle, separated from the foot by a groove. The respiratory cavity open throughout the whole length of the mantle, bearing on its right margin a long and narrow branchia. The heart has a direction from right to left. The rectum and uterus are attached to each other along the branchiae, and terminate in an ear-shaped gutter, produced by the margin of the mantle. The mucous follicles line the upper wall of the cavity. The foot is round, without a marginal furrow, passing down before in form of an ear-shaped shield, and bearing posteriorly a membranous operculum, with laminas destitute of a spire, which possesses one or two notches to slip upon the folds of the columella.[5]
^Rosenberg, G. (2010). Pyramidella camara Bartsch, 1927. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at
http://www.marinespecies.org/aphia.php?p=taxdetails&id=533354 on 2011-03-15
^Rosenberg, G. (2010).Pyramidella sanctaehelenae (E. A. Smith, 1890). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at
http://www.marinespecies.org/aphia.php?p=taxdetails&id=533356 on 2011-03-15
^Rosenberg, G. (2010). Pyramidella subdolabrata (Mörch, 1854). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at
http://www.marinespecies.org/aphia.php?p=taxdetails&id=533357 on 2011-03-15
^Rosenberg, G. (2010). Pyramidella folinii Dall, 1889. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at
http://www.marinespecies.org/aphia.php?p=taxdetails&id=533355 on 2011-03-15
Lamarck, J.B.P.A. de Monet de 1799. Prodrome d'une nouvelle classification de coquilles, comprenent une réaction appropiée de charactères génériques, et l'établissement d'un grand nombre de genres nouveaux. Mémoires de la Société d'Histoire Naturelle de Paris 1: 63-91
Vaught, K.C. (1989). A classification of the living Mollusca. American Malacologists: Melbourne, FL (USA).
ISBN0-915826-22-4. XII, 195 pp.
External links
Wikimedia Commons has media related to Pyramidella.
Pyramidella is the
type genus of the family Pyramidellidae.[2]
Nomenclature
The generic name Pyramidella Lamarck, 1799, has been validated under the Plenary Powers of the
ICZN , Opinion 386 (1955). The name Obeliscus Anonymus, 1797 [= Obeliscus Gray, 1847] has also been used for this genus, whereas the name Pyramidella was used for the genus now known as Otopleura Fischer, 1885.[1]
General description
The shell has an elongate-conic shape, slightly striated. The many
whorls of the
teleoconch are usually inflated and regularly increasing. They are longitudinally ribbed or smooth. The semioval
aperture is entire, widened at its base and rounded in front. .The
columella has one to three folds. The sharp
outer lip is entire, inferiorly sub-perforated and often plicate within with three transverse folds. The shell is usually larger than in Turbonilla. The thin
operculum is horny, ovate, elongated, with very fine elements and oblique folds
and folds oblique. The shell lacks an
epidermis.[3][4][5]
The shells are generally quite small, of an elegant form, elongated, marked with more or less deep spots. The general color of the body of these mollusca, is of a dull white. The operculum only, and the edge of the mantle are yellowish.[5]
The animal has a head surmounted by broad, rather long tentacles, formed like a pointed horn, and open on the side. The mouth is situated in a flattened, wide, dilated, and quite deeply two-lobed muzzle, separated from the foot by a groove. The respiratory cavity open throughout the whole length of the mantle, bearing on its right margin a long and narrow branchia. The heart has a direction from right to left. The rectum and uterus are attached to each other along the branchiae, and terminate in an ear-shaped gutter, produced by the margin of the mantle. The mucous follicles line the upper wall of the cavity. The foot is round, without a marginal furrow, passing down before in form of an ear-shaped shield, and bearing posteriorly a membranous operculum, with laminas destitute of a spire, which possesses one or two notches to slip upon the folds of the columella.[5]
^Rosenberg, G. (2010). Pyramidella camara Bartsch, 1927. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at
http://www.marinespecies.org/aphia.php?p=taxdetails&id=533354 on 2011-03-15
^Rosenberg, G. (2010).Pyramidella sanctaehelenae (E. A. Smith, 1890). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at
http://www.marinespecies.org/aphia.php?p=taxdetails&id=533356 on 2011-03-15
^Rosenberg, G. (2010). Pyramidella subdolabrata (Mörch, 1854). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at
http://www.marinespecies.org/aphia.php?p=taxdetails&id=533357 on 2011-03-15
^Rosenberg, G. (2010). Pyramidella folinii Dall, 1889. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at
http://www.marinespecies.org/aphia.php?p=taxdetails&id=533355 on 2011-03-15
Lamarck, J.B.P.A. de Monet de 1799. Prodrome d'une nouvelle classification de coquilles, comprenent une réaction appropiée de charactères génériques, et l'établissement d'un grand nombre de genres nouveaux. Mémoires de la Société d'Histoire Naturelle de Paris 1: 63-91
Vaught, K.C. (1989). A classification of the living Mollusca. American Malacologists: Melbourne, FL (USA).
ISBN0-915826-22-4. XII, 195 pp.
External links
Wikimedia Commons has media related to Pyramidella.