Chondrichthyes - Thrinacodontidae
Full reference: E. D. Grogan and R. Lund. 2008. A basal elasmobranch, Thrinacoselache gracia n. gen and sp., (Thrinacodontidae, new family) from the Bear Gulch Limestone, Serpukhovian of Montana, USA. Journal of Vertebrate Paleontology 28(4):970-988
Parent taxon: Elasmobranchii according to E. D. Grogan and R. Lund 2008
Sister taxa: Agaleidae, Amelacanthus, Annulicorona, Aporomicrodus, Arduodens, Batomorphi, Carcharopsis, Carinasubcorona, Celtiberina, Cestraciontidae, Changxingselache, Cladodontomorphi, Cladodontomorphii, Cladodus hassiacus, Cladodus wildungensis, Cladoselachida, Cladoselachii, Complanicorona, Coniunctio, Coronodontida, Eunemacanthus, Euselachiformes, Eychlaodus, Fragilicorona, Galeiformes, Galeomorphi, Glabrisubcorona, Gondwanodus, Ichthyodorulites, Labascicorona, Labrilancea, Lamna (Sphenodus) longidens, Leonodus, Lesnilomia, Lobaticorona, Lugalepididae, Mcmurdodontidae, Meishanselache, Minuticorona, Oniscina, Ornathiliabrilance, Ornatilabrilancea, Orodontida, Orthacodus, Ostenoselachidae, Osteodonti, Parvicorona, Parvidiabolus, Parviscapha, Physonemus, Plagiostomi, Platylithophycus, Pleuracanthidae, Pleuracanthodii, Pristiorajea, Proselachii, Raineria, Rosaodus, Rugosicorona, Sacrisubcorona, Selachii, Serratocorona, Siamodus, Sphenodus, Sphenodus plana, Squalomorphi, Suaviloquentia, Undulaticorona, Xenacanthida
Subtaxa: Thrinacoselache
Ecology: nektonic carnivore
Distribution: found only at Bear Gulch Limestone Lens (Carboniferous of Montana)