Dallina
Dallina is a genus of small to average size lampshells. 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, these are listed below:- Dallina septigera, 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, 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.
- Dallina profundis Konjukova, 1957
- Dallina raphaelis, recorded from off Japan.
- Dallina tasmaniaensis Verhoeff, 2023, southeastern Australia.
- Dallina triangularis Yabe & Hatai, 1934, recorded from off Japan and possibly Lau Ridge.