Dallina

Dallina is a genus of small to average size lampshells (maximum 35 mm long). It is known since the Miocene.

Description
Small to large, triangular to subquadrangular in outline; rectimarginate to paraplicate; beak erect, without beak ridges; foramen small to large, mesothyrid, attrite, symphytium concave. Hinge teeth small, weak; pedicle collar very short. Cardinalia lamellar with excavate inner and outer hinge plates separated by narrow crural bases; inner hinge plates converging on median septum to form V-shaped septalium; cardinal process not differentiated; median septum low anteriorly, extending beyond midvalve; adult loop teloform.

Taxonomy
Nine extant species are recognized (though one has recently been synonymized), these are listed below:


 * Dallina septigera (Lovén, 1845), Type species of genus, from northeastern Atlantic.
 * Dallina elongata Hatai, 1940, recorded from Sea of Japan.
 * Dallina eltanini Foster, 1974, southern Pacific, near Antarctica.
 * Dallina floridana (Pourtalès, 1867), recorded from the Gulf of Mexico and Bahamas.
 * Dallina obessa Yabe & Hatai, 1934, recorded from Sea of Japan.
 * Dallina parva Cooper, 1981, recorded from northeast Atlantic (Bay of Biscay).
 * Dallina profundis Konjukova, 1957 (junior synonym of Glaciarcula spitzbergensis )
 * Dallina raphaelis (Dall, 1970), recorded from off Japan.
 * Dallina tasmaniaensis Verhoeff, 2023, southeastern Australia.
 * Dallina triangularis Yabe & Hatai, 1934, recorded from off Japan and possibly Lau Ridge.