Rodzaj Promathildia Andreae, 1887
Gatunek typowy Opis Protoconch hyperstrophic, diverging more than 100° from teleoconch axis, smooth or, in some species with adapical and abapical, axial folds. Teleoconch slender to broadly cone−shaped. First teleoconch whorl with two spiral ribs of which abapical one usually distinctly angulating whorls. Number of spiral ribs stable during ontogeny or increasing to three. Spiral ribs crossed by weaker axial ribs, threads or enhanced growth lines, at rib intersections usually without nodes. Synonimy Zasięg czasowy Late Triassic to Early Cretaceous. Literatura Kaim, A. 2004. The evolution of conch ontogeny in Mesozoic open sea gastropods. Palaeontologia Polonica 62, 3–183. |
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