Turbonilla crystallina

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Turbonilla crystallina
Drawing of a shell of Turbonilla crystallina
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Heterobranchia
clade Euthyneura
clade Panpulmonata
Superfamily: Pyramidelloidea
Family: Pyramidellidae
Subfamily: Turbonillinae
Genus: Turbonilla
Species: T. crystallina
Binomial name
Turbonilla crystallina
Dall & Bartsch, 1906 [1]
Synonyms[2]
  • Chemnitzia crystallina Dunker, 1869
  • Turbonilla lydia Thiele, 1925
  • Turbonilla (Nisiturris) crystallina Dall & Bartsch, 1906 (basionym)

Turbonilla crystallina is a species of sea snail, a marine gastropod mollusk in the family Pyramidellidae, the pyrams and their allies.[2][3]

Description

Pupoid protoconch (enlarged) of Turbonilla crystallina

The very slender and thin, almost transparent shell has an elongate-conic shape. Its length varies between 2.9 mm and 4.5 mm. It is slightly umbilicated. The smooth whorls of the protoconch are large, and very much elevated. They are coiled to resemble a small sinistral pupa. This pupoid shape makes this species peculiar, as most species in Turbonilla have a helicoid or planorboid protoconch. It is situated obliquely upon the spire of the whorls of the teleoconch and extending considerably beyond the lateral outline of this. The 12 whorls of the teleoconch are situated rather high between the sutures, somewhat overhanging (this is particularly true of the earlier volutions), and slightly shouldered at the summit. They are ornamented by strong, oblique, rounded axial ribs, which are slightly cusped at their posterior extremity, where they show a tendency toward becoming fused at the periphery. Twenty-two of these ribs occur upon the first (this whorl is more rounded than the rest and closer ribbed), fourteen upon the second, twelve upon the fifth, sixteen upon the tenth, and twenty upon the penultimate whorl. The intercostal spaces are twice as wide as the ribs, decidedly depressed, smooth, and terminating at the fusing point of the ribs on the periphery. The summits of succeeding whorls fall somewhat anterior to the periphery of the preceding whorl and give the whorls an overhanging effect as well as a narrow smooth band between the anterior termination of the intercostal spaces and the subchanneled sutures. The periphery and the base of the body whorl are well rounded, the latter very short, marked only by faint lines of growth. The aperture is very large, almost circular in outline. The outer lip is thin, transparent, and showing the external sculpture within. The columella is thin, curved and revolute, with a slight oblique fold near its insertion. The parietal wall is covered by a mere film of callus. [1]

Distribution

This species occurs in the Pacific Ocean off Indonesia, Samoa, Vanuatu; Fiji and the Solomons

References

  1. 1.0 1.1 Dall & Bartsch (1906), Notes on Japanese, Indopacific, and American Pyramidellidæ; Proceedings of the National Museum, vol. XXX # 1452; p. 341
  2. 2.0 2.1 Bouchet, P. (2010). Turbonilla crystallina Dall & Bartsch, 1906. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=545291 on 2012-03-01
  3. Peñas A. & Rolán E. (2010) Deep water Pyramidelloidea of the Tropical South Pacific: Turbonilla and related genera. In: Gofas S. (ed.) Tropical Deep Sea Benthos 26. Mémoires du Muséum National d'Histoire Naturelle 200:1-436.

External links

External identifiers for Turbonilla crystallina
Encyclopedia of Life 4811093
WoRMS 545291
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