Gatunek typowy
Bittium valanginense Schröder, 1995. Valanginian, Wąwał near Tomaszów Mazowiecki, Poland.

Opis

Small slender, tall tower−like shell with weakly globose, suturally constricted  whorls. Sculpture of early teleoconch consisting of orthocline growth lines and of two rows of thorns which are connected by weak or indistinct spiral ribs. Number of rows increasing during ontogeny. Shape of peristomeround and narrowed at edge, somewhat flattened at base. Protoconch of three to five whorls conical and orhostrophic. Protoconch 1 weakly rounded or flat. Sculpture of protoconch 2 consisting of tuberculate spiralkeels  medially  and  basally  arranged.  Transition  to  teleoconch  demarcated  by  lamella−like  thickening  ofgrowth lines.

Synonimy

Zasięg czasowy

Valanginian to Campanian, Cretaceous.

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.