Rodzaj Bactroptyxis Cossmann, 1896
Gatunek typowy Opis The shell almost cylindrical; coils are extremely elongated, higher than wide, separated by a suture on a fine protruding ridge, smooth or ornamentes with spiral ridges. Aperture narrow, rhomboidal; right labrum with two or three internal folds, the middle one almost always subdivided, the lower one sometimes very obsolete.The somewhat concave columella provided with three folds and a weak parietal fold; the anterior fold is the most complicated and the most prominent, it delimits the anterior canal of the opening. Synonimy Zasięg czasowy Mid Jurassic (Bajocian) - Late Jurassic (Kimmeridgian) Literatura Cossmann, M. 1896. Essais de paléoconchologie comparée, vol. 2. 179 pp., Paris. |
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