Specimen BGR X 12925 from the Late Oxfordian of Kłęby (Western Pomerania) in Lateral and Apical view.

Diagnoza

The shell is broadly conical, or very occasionally, slender. The lateral flank is weakly convex and the suture is distinctly incised. A ramp is absent and the shell surface is smooth apart from very fine lirae that are visible only on the best-preserved specimens. The growth lines are prosocline and bent posteriorly. The base is convex. The aperture is drop-like shaped with the anterior part broadly rounded. The parietal and columellar parts of the inner lamella form a concave curve without any angulation.

Porównanie

The shells described but not illustrated by Schmidt (1905, p. 187) as juvenile individuals of Pseudomelania collisa most probably belong to Pictavia elegans but the specimen is probably lost. Pseudomelania collisa lacks a ramp and the protoconch has a thickened outer lip, features that are typical of Pictavia. Other Pictavia-like species that could be synonymised are: Pseudomelania (Oonia) remtsaensis Cox, 1969 from the early Callovian of Tunisia (Cox 1969), Coelostylina mandawaensis Cox, 1965 from the ?Bajocian of eastern Africa (Cox, 1965), and in part Pictavia nikitensis Pcelincev, 1963 from the Oxfordian of the Crimea.

Autekologia

Występowanie geograficzne

England, France; in Poland only in Kłęby (Western Pomerania); probably also Bajocian-Oxfordian of East Africa, Tunisia and Crimea.

Zasięg czasowy

Bathonian to late Oxfordian

Materiały muzealne

Material from England, France (MNHN) and Poland (35 specimens: BGR, Buchholz, and GG).

Literatura

Cossmann, M. 1909. Essais de Paléoconchologie Comparée. Huitieme Livraison. 248 pp. M. Cossmann, F. R. de Rudeval; Paris.

Gründel, J & Kaim, A. 2006. Shallow-water gastropods from Late Oxfordian sands in Kłęby (Pomerania, Poland). Acta Geologica Polonica 56, 121‒157.

Morris, J. & Lycett, J. 1851. A monograph of the Mollusca from the Great Oolite, chiefly from Minchinhampton and the coast of Yorkshire. Part I. Univalves. Palaeontographical Society Monograph, 1850, 1‒13.

Schmidt, M. 1905. Über Oberen Jura in Pommern. Abhandlungen der Königlich Preußsischen Geologischen Landesanstalt und Bergakademie, Neue Folge, 41, 1‒222.