Specimen ZPAL Ga.9/65 from the Early Valanginian (Early Cretaceous) of Wąwał; lateral and apical view; black arrows indicate demarcation between protoconch 1 and protoconch 2; white arrows indicate demarcation between protoconch and teleoconch.

Diagnoza

Small slender shell with incised sutures. Protoconch 2 of 4.5 whorls, angulated with one spiral keel and two spiral ribs. Keel and ribs starting at second whorl of protoconch 2, keel situated medially and ribs situated laterally. Sinusigera lip well developed at peristome of protoconch 2 . Teleoconch ornamented with wide weak axial ribs and two spiral ribs. Distinct nodes appearing at intersections. Axial ribs of teleoconch orthocline.

Porównanie

This species is known from juvenile (or micromorphic?) shells only. The protoconch  and the juvenile whorls of the teleoconch are very similar to Schroederium cowickeense (Sohl, 1964).

Autekologia

Występowanie geograficzne

Only in type locality.

Zasięg czasowy

Busnardoides campylotoxus Zone of Early Valanginian (Early Cretaceous).

Materiały muzealne

ZPAL: 197 shells.

Literatura

Kaim, A. 2004. The evolution of conch ontogeny in Mesozoic open sea gastropods. Palaeontologia Polonica 62, 3–183.

Kowalke, T. 1998. Bewertung protoconchmorphologischer Daten basaler  Caenogastropoda  (Cerithiimorpha  und  Littorinimorpha) hinsichtlich ihrer Systematik und Evolution von der Kreide bis rezent. Berliner Geowissenschaftliche Abhandlungen, Reihe E27, 1–121.

Schröder, M. 1995. Frühontogenetische Schalen jurassicher und unterkretazischer Gastropoden aus Norddeutschland und Polen. Palaeontographica, Abteilung A238, 1–95.