Odostomia tyleri

Odostomia tyleri
Drawing of a shell of Odostomia tyleri
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Heterobranchia
clade Euthyneura
clade Panpulmonata
Superfamily: Pyramidelloidea
Family: Pyramidellidae
Genus: Odostomia
Species: O. tyleri
Binomial name
Odostomia tyleri
Dall & Bartsch, 1909
Synonyms
  • Chrysallida tyleri (Dall & Bartsch, 1909)
  • Odostomia (Chrysallida) tyleri Dall & Bartsch, 1909 (basionym)

Odostomia tyleri is a species of sea snail, a marine gastropod mollusk in the family Pyramidellidae, the pyrams and their allies.[1][2]

This species is named after Prof. J.M. Tyler.

Description

The robust shell is subdiaphanous to milk-white. The whorls of the protoconch are smooth. They are immersed in the first of the succeeding turns, above which only a part of the decidedly tilted edge of the last whorl projects. The seven whorls of the teleoconch are flattened, slightly excurved at the summit, scarcely at all contracted at the periphery and moderately shouldered at the summit. They are marked by very strong, rounded, axial ribs, of which 14 occur upon the first, 16 upon the second, 18 upon the third, 20 upon the fourth, 22 upon the fifth, and 24 upon the penultimate turn. In addition to the axial ribs the whorls are marked by spiral cords, less strong than the ribs, the junctions of which with the ribs render them tuberculate. Of these cords, four occur upon all the whorls but the penultimate and last, which have five between the sutures. The spaces enclosed between the ribs and cords are deep square pits. The posterior cord is on the summit of the whorl and is a little stronger than the rest, rendering the whorls, which are excurved, crenulated. The sutures are well marked but not channeled. The periphery and the somewhat attenuated base of the body whorl are well rounded. They are marked by seven strong, rounded, spiral cords which diminish successively in size and spacing from the periphery to the umbilical area. The channels which separate the cords are marked by numerous fine axial riblets. The aperture is irregularly pyriform, and somewhat effuse anteriorly. The posterior angle is obtuse. The outer lip is thin, showing the external sculpture within. The columella is stout, twisted, curved, and slightly reflected. It is reinforced by the base and provided with a strong fold at its insertion. The parietal wall is covered by a strong callus, which practically renders the peritreme complete. [3]

Distribution

The type species was found in the Pacific Ocean off the Bay of Panama.

References

  1. WoRMS (2011). Odostomia tyleri Dall & Bartsch, 1909. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=575922 on 2012-01-12
  2. Keen M. (1971). Sea shells of Tropical West America. Marine mollusks from Baja California to Perú. (2nd edit.). Stanford University Press pp. 1064:
  3. Dall & Bartsch, A Monograph of West American Pyramidellid Mollusks, United States National Museum Bulletin 68, 1 p. 157-158; 1909

External links

External identifiers for Odostomia tyleri
WoRMS 575922
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