Frenulina Sous-embranchement (subphylum) des Rhynchonelliformea Classe des Rhynchonellata Ordre des Terebratulida Sous-Ordre des Terebratellidina Super-famille des Laqueoidea

Genus Frenulina Dall, 1895

[Type species= Anomia sanguinolenta Gmelin, 1791 (p. 3347)]

Small, biconvex, smooth, commonly reddish-orange with white mottling, unisulcate, beak suberect, foramen submesothyrid; deltidial plates commonly disjunct, occasionally conjunct. Hinge teeth with ventrally recessive dental plates; pedicle collar sessile. Cardinalia divergent from apex with inner socket ridges rather strong, united on their inner sides to crural bases; inner hinge plates rudimentary and not united medianly; cardinal process small, striated myophore; loop bilacunar to incipiently bilateral.

Pliocene-Present Diagnosis from volume 5 of the Treatise on Invertebrate Paleontology (2006)

Extant Species of Frenulina

F. sanguinolenta (Gmelin, 1791) F. mauiensis Dall, 1920 F. cruenta Cooper, 1973

Diagnosis

Frenulina sanguinolenta   (Gmelin, 1791) Type locality: "Habitat in India, testa pellucida." Depth range: 5 - 541 m Anomia sanguinolenta Gmelin, 1791, p. 3347. Diagnosis (Gmelin, 1791, p. 3347) A. tefta cornea laevi utrinque convexa : valva superiore emarginata ad latera radiata ; dorso elevato sanguineo, apiceque prominente perforato.	collected in 2012 near Mindanao, Philippines [https://en.wikipedia.org/wiki/Frenulina]