Sous-embranchement (subphylum) des Rhynchonelliformea  
Classe des Rhynchonellata 
Ordre des Terebratulida 

Sous-ordre des Terebratulidina 
Super-famille des Terebratuloidae 
Super-famille des Dyscolioidae 
Super-famille des Cancellothyroidea 

Genus Dallithyris Muir-Wood, 1959
[= Epacrosina Cooper, 1983]
[Type species = Liothyrina fulva Blochmann, 1913 (p. 113)]

Medium to large, subtrigonal to subpentagonal; ventribiconvex, anterior commissure rectimarginate to broadly uniplicate; beak suberect, short, labiate; foramen large, submesothyrid; symphytium short; cardinal process small semiellipse; outer hinge plates broadly triangular, crural bases poorly defined; loop narrow, variable.

?Eocene, Pliocene - Present

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

NOTA: According to the ICZN (2000) this species name cited by Blochmann (1906, 1908) failing to conform to Article 12 must be considered as a nomen nudum until its real description by Blochmann in 1913 (p. 113-114).
In the same way, Blochman (1913, p. 113) states: "the species Terebratula (Liothyrina) fulva, created by me in 1908, which was known hitherto only by one single empty shell, obtained by the Challenger expedition from Twofold Bay, on the South-East Coast of Australia."

Extant Species of Dallithyris
  • D. fulva (Blochmann, 1913)
  • D. murrayi Muir-Wood, 1959
  • ? D. dubia Cooper, 1981
  • D. pacifica Bitner, 2006
  • D. tahitiensis Bitner, 2014
  • Diagnosis


    Dallithyris fulva   (Blochmann, 1913)

    Type locality: Twofold Bay (South-East Coast of Australia)
    Depth range: 165 - 275 m

    Diagnosis in preparation -

    Dallithyris murrayi   Muir-Wood, 1959

    Type locality: xx
    Depth range: 240 - 970 m

    Diagnosis in preparation -

    Dallithyris pacifica   Bitner, 2006

    Type locality: Bligh Water, Fidji [16°52.8'S, 178°03.0'E]
    Depth range: 640 - 753 m

    Diagnosis - Bitner (2006)

    Dallithyris of medium size with thin, cream coloured shell, pentagonal in outline, anterior commissure rectimarginate.

    Dallithyris tahitiensis   Bitner, 2014

    Type locality: Society Islands, st. DW 3436, 430 m [16° 43'S, 151° 26'W]
    Depth range: 340 - 1050 m

    Diagnosis - Bitner (2014)

    Dallithyris of medium to large size with cream-colored shell. Oval elongate in outline. Anterior commissure widely unisulcate. Beak suberect, foramen large. Loop narrow, transverse band broad with a strong but rounded median fold.