† Priotrochus obscurus ponsonbyi (G. B. Sowerby, 1888) (synonyms: Monilea (Priotrochus) ponsonbyi (G. B. Sowerby, 1888); Monilea obscura ponsonbyi (G.B. Sowerby, 1888); Monilea ponsonbyi (G.B. Sowerby, 1888); Priotrochus alexandri Tomlin, 1926; Trochus (Gibbula) ponsonbyi G. B. Sowerby, 1888; Trochus ponsonbyi G.B. Sowerby, 1888)
Description
The shell size varies between 7 mm and 20 mm. The very solid, thick, narrowly perforated shell has a conical shape and is elevated. It is ashen-white, with longitudinal chestnut streaks or maculations. The
spire is elevated. The
apex is acute. The
sutures are slightly impressed, the
whorl below them closely appressed. The shell contains 6 to 7 whorls. The upper ones are subangular and nodulose in the middle. The
body whorl shows a coronal series of knobs, on large specimens becoming obsolete toward the
aperture. The entire surface is traversed by spiral lirulae, much narrower than the densely obliquely striate interstices. The oblique, ovate aperture is about half the length of shell. The outer
lip is bevelled to an edge. The aperture is spirally lirate. The edge of the
columella is denticulate. Its upper insertion is callous, partly or nearly covering the
umbilicus. Young specimens are subbiangulate with nodulose periphery.[3]
^
abPriotrochus obscurus (Wood, 1828). Bouchet, P. (2010). Priotrochus obscurus (W. Wood, 1828). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=546929 on 13 March 2011 .
Dautzenberg, Ph. (1929). Mollusques testacés marins de Madagascar. Faune des Colonies Francaises, Tome III
Spry, J.F. (1961). The sea shells of Dar es Salaam: Gastropods. Tanganyika Notes and Records 56
Herbert D.G. (1988). A new species of Priotrochus (Mollusca: Gastropoda: Trochidae) from south-east Africa. Annals of the Natal Museum 29(2):503–507
Herbert D.G. (1994). Trochus kotschyi, the first Indian Ocean record of the genus Osilinus (Mollusca: Gastropoda: Trochidae). Journal of Zoology 233:345–357.
Bonfitto A., Sabelli B., Tommasini S. & Herbert D. (1994). Marine molluscan taxa from Mozambique described by G.G. Bianconi and preserved in the Zoological Museum of the University of Bologna. Annals of the Natal Museum 35:133–138.
Zuschin, M., Janssen, R. & Baal, C. (2009). Gastropods and their habitats from the northern Red Sea (Egypt: Safaga). Part 1: Patellogastropoda, Vetigastropoda and Cycloneritimorpha. Annalen des Naturhistorischen Museums in Wien 111[A]: 73–158. page(s): 104