Sous-embranchement (subphylum) des Rhynchonelliformea  
Classe des Rhynchonellata 
Ordre des Rhynchonellida 
Super-famille des Pugnacoidea 
Super-famille des Dimerelloidea 
Super-famille des Norelloidea 
Super-famille des Hemithiridoidea 

Genus Cryptopora Jeffreys, 1869
[= Atretia Jeffreys 1870; Mannia Davidson, 1874; Neatretia Fischet & Œhlert, 1891; Crytopora Cooper, 1959]
[Type species= Cryptopora gnonom = Atretia gnonom Jeffreys, 1869 (p. 136)]
Small, translucent, subtrigonal to ovoid-lenticular, almost equibiconvex; rectimarginate to broadly sulcate, smooth; beak moderately long, pointed, nearly straight; foramen large, incomplete; deltidial plates auriculate, rudimentary, disjunct. Dental plates distinct, subvertical; cardinal process small and transverse; dorsal median septum high; crura digitate distally.
lower Danian - Present

Diagnosis from volume 4 of the
Treatise on Invertebrate Paleontology (2002)

Extant Species of Cryptopora
  • C. gnomon Jeffreys, 1869
  • C. boettgeri Helmcke, 1940
  • C. rectimarginata Cooper, 1959
  • C. maldiviensis Muir-Wood, 1959
  • C. curiosa Cooper, 1973
  • C. hesperis Cooper, 1982
  • C. norfolkensis (Bitner, 2009)
  • Diagnosis

    Cryptopora gnomon Jeffreys, 1869

    Type locality: No information on location in Jeffreys (1869) and Carpenter et al. (1869), but in Jeffreys (1876), this species has been sampled “during the 'Porcupine' expedition of 1869, in stations 20 [55°11'N, 11°31'W, 2639 m] and 30 [56°24'N, 11°49'W, 2524 m], at depths of 1443 ann 1380 fathoms, off the west coast of Ireland.”
    Depth range: 300 - 5950 m

    Cryptopora gnomon Jeffreys, 1869, p. 136
    Atretia gnonom: Jeffreys, 1876, p. 250
    Dimerella gnonom: Dall, 1873, p. 197
    Neatretia gnomon Fischer & Œhlert, 1891

    Diagnose - Jeffreys 1869, p. 136

    "Among the Mollusca were valves of an imperforate Brachiopod with a septum in the lower valve, which I propose to name Cryptopora gnomon. Some shells were of a tolerable size ;"