Dallina

Dallina Temporal range: Miocene–Recent PreꞒ Ꞓ O S D C P T J K Pg N
Dallina septigera, 23mm wide, recent
Scientific classification
Kingdom:	Animalia
Phylum:	Brachiopoda
Class:	Rhynchonellata
Order:	Terebratulida
Family:	Dallinidae
Subfamily:	Dallininae
Genus:	Dallina Beecher, 1893
Species
See text

Dallina is a genus of small to average size lampshells (maximum 35 millimetres or 1.4 inches 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.

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  Dallina septigera, brachial valve, 24mm long, near the Philippines
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  pedicle valve
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  anterior view
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  interior view
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  lateral view

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.

References