Mathilda malvinarum Melvill & Standen 1907

Mathilda malvinarum (Melvill & Standen, 1907) Fig. 5D Cerithiopsis malvinarum Melvill & Standen, 1907: 135, figs. 6, 6a; Strebel, 1908: 49, pl. 1, figs. 10a–c Mathilda malvinarum — Powell, 1951: 113 Examined material. 10 sh. (MACN-In 40700). Description. Shell height to 2.8 mm (up to 4 mm ac...

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Bibliographic Details
Main Authors: Luca, Javier Di, Zelaya, Diego G.
Format: Text
Language:unknown
Published: Zenodo 2019
Subjects:
Online Access:https://dx.doi.org/10.5281/zenodo.5934699
https://zenodo.org/record/5934699
Description
Summary:Mathilda malvinarum (Melvill & Standen, 1907) Fig. 5D Cerithiopsis malvinarum Melvill & Standen, 1907: 135, figs. 6, 6a; Strebel, 1908: 49, pl. 1, figs. 10a–c Mathilda malvinarum — Powell, 1951: 113 Examined material. 10 sh. (MACN-In 40700). Description. Shell height to 2.8 mm (up to 4 mm according to Melvill & Standen 1907); turritelliform, moderately solid. Protoconch large, of 1 markedly convex whorl; sculptured with 4 low, wide spiral cords. Teleoconch of up to 5.75 whorls, markedly convex in outline; last whorl comprising about 45% of total shell height. Suture impressed. Surface pale brownish, clearer at spiral sculpture; sculptured with 25 to 30 axial ribs per whorl and 4 spiral cords, the 2 adapical being stronger. Base delimited by a strong cord and sculptured with up to 9 additional, narrower cords. Aperture almost rounded, somewhat projected anteriorly, interior brownish with lighter margin; columellar callus narrow, slightly reflected. Remarks. The original figure by Melvill & Standen (1907) only shows 2 spiral cords per whorl. However, Strebel (1908), who studied the same specimens, figured four spiral cords per whorl, a condition similar to that found in the material here examined. : Published as part of Luca, Javier Di & Zelaya, Diego G., 2019, Gastropods from the Burdwood Bank (southwestern Atlantic): an overview of species diversity, pp. 41-78 in Zootaxa 4544 (1) on page 63, DOI: 10.11646/zootaxa.4544.1.2, http://zenodo.org/record/2618137 : {"references": ["Melvill, J. C. & Standen, R. (1907) The marine Mollusca of the Scottish National Antarctic Expedition. Transactions of the Royal Society of Edinburgh, 46, 119 - 157, 1 pl.", "Strebel, H. (1908) Die Gastropoden (mit Ausnahme de nackten Opisthobranchier). Wissenschaftliche Ergebnisse der Schwedischen Sudpolar-Expedition 1901 - 1903, 6 (1), 1 - 112, pls. 1 - 6.", "Powell, A. W. B. (1951) Antarctic and Subantarctic Mollusca: Pelecypoda and Gastropoda collected by the ships of the Discovery Committee during the years 1926 - 1937. Discovery Reports, 26, 49 - 196, pls. 5 - 10."]}