The elongate-conic shell is vitreous. It measures 2.8 mm. The whorls of the protoconch are small, smooth, and almost completely obliquely immersed in the first of the succeeding turns, above which only the tilted edge of the last volution projects. The six whorls of the teleoconch are flattened, strongly contracted at the sutures and moderately shouldered at the summit. They are marked by strong, tuberculate retractive axial ribs, of which 18 occur upon the first and second and 20 upon the remaining turns. In addition to these axial ribs the whorls are marked by four slender, spiral cords between the sutures, which pass over the axial ribs and render them tuberculate at their junction. The spaces enclosed by the ribs and cords are rectangular pits, which have their long axis parallel with the spiral cords. The sutures are channeled. The periphery of the body whorl is marked by a spiral groove. The base of the body whorl is well rounded, and marked by eight spiral cords which grow successively weaker and closer spaced from the periphery to the umbilical area. The wide grooves between the spiral cords are marked by slender, raised, axial threads, which correspond to the ribs on the spire. The aperture is ovate and somewhat effuse anteriorly. The posterior angle is obtuse. The outer lip is thin, showing the external markings within. The columella is stout, strongly reflected, and provided with a slender fold at its insertion. The parietal wall is covered by a strong callus.[4]
Distributionedit
This species occurs in the Pacific Ocean from California to Mexico.
^Keen M. (1971). Sea shells of Tropical West America. Marine mollusks from Baja California to Perú. (2nd edit.). Stanford University Press pp. 1064:
^William Healy Dall and Paul Bartsch , "A Monograph of West American Pyramidellid Mollusks" , Smithsonian Institution, 1909
External linksedit
To World Register of Marine Species
May 07, 2024
odostomia, effusa, species, snail, marine, gastropod, mollusc, family, pyramidellidae, pyrams, their, allies, apertural, view, shell, scientific, classification, domain, eukaryota, kingdom, animalia, phylum, mollusca, class, gastropoda, subclass, heterobranchi. Odostomia effusa is a species of sea snail a marine gastropod mollusc in the family Pyramidellidae the pyrams and their allies 2 3 Odostomia effusa Apertural view of the shell of Odostomia effusa Scientific classification Domain Eukaryota Kingdom Animalia Phylum Mollusca Class Gastropoda Subclass Heterobranchia Family Pyramidellidae Genus Odostomia Species O effusa Binomial name Odostomia effusaCarpenter 1856 1 Synonyms Chrysalida effusa Carpenter 1857 Odostomia Chrysallida effusa Carpenter 1856 basionym Contents 1 Description 2 Distribution 3 References 4 External linksDescription editThe elongate conic shell is vitreous It measures 2 8 mm The whorls of the protoconch are small smooth and almost completely obliquely immersed in the first of the succeeding turns above which only the tilted edge of the last volution projects The six whorls of the teleoconch are flattened strongly contracted at the sutures and moderately shouldered at the summit They are marked by strong tuberculate retractive axial ribs of which 18 occur upon the first and second and 20 upon the remaining turns In addition to these axial ribs the whorls are marked by four slender spiral cords between the sutures which pass over the axial ribs and render them tuberculate at their junction The spaces enclosed by the ribs and cords are rectangular pits which have their long axis parallel with the spiral cords The sutures are channeled The periphery of the body whorl is marked by a spiral groove The base of the body whorl is well rounded and marked by eight spiral cords which grow successively weaker and closer spaced from the periphery to the umbilical area The wide grooves between the spiral cords are marked by slender raised axial threads which correspond to the ribs on the spire The aperture is ovate and somewhat effuse anteriorly The posterior angle is obtuse The outer lip is thin showing the external markings within The columella is stout strongly reflected and provided with a slender fold at its insertion The parietal wall is covered by a strong callus 4 Distribution editThis species occurs in the Pacific Ocean from California to Mexico References edit Carpenter Cat Mazatlan Shells 1856 p 422 WoRMS 2011 Odostomia effusa Carpenter 1857 Accessed through World Register of Marine Species at http www marinespecies org aphia php p taxdetails amp id 575840 on 2011 11 10 Keen M 1971 Sea shells of Tropical West America Marine mollusks from Baja California to Peru 2nd edit Stanford University Press pp 1064 William Healy Dall and Paul Bartsch A Monograph of West American Pyramidellid Mollusks Smithsonian Institution 1909External links editTo World Register of Marine Species Retrieved from https en wikipedia org w index php title Odostomia effusa amp oldid 1023509380, wikipedia, wiki, book, books, library,
