Stethacanthidae
（重定向自Stethacanthid）
![Complete skeleton of Akmonistion zangerli (HMV8246, Hunterian Museum, University of Glasgow). Photograph taken by Dr. Keith Ingham, published in Coates & Sequira, 2001.[1]](/uploads/202502/13/te_Stethacanthid_sp._skeleton._Akmonistion_zangerli_specimen_HMV8246_of_the_Hunterian_Museum,_University_of_Glasgow._Photograph_taken_by_Dr._Keith_Ingham,_published_in_Coates_&_Sequeira_(2001)5923.gif)
![Hand drawing of Stethacanthus altonensis first dorsal fin and spine (M.V. 2830, University of Montana Vertebrate Collection). SP: first dorsal fin spine, BP: basal plate. By Lee Ambrose, published in Lund, 1974.[4]](/uploads/202502/13/Drawing_of_Stethacanthus_altonensis,_M.V.2830,_first_dorsal_fin_and_spine._From_LUND,_R._(1974)_Stethacanthus_altonensis_(Elasmobranchii)_from_the_Bear_Gulch_Limestone_of_Montana.pdf5923.svg)
Stethacanthidae is an extinct family of prehistoric sharks. It is estimated to have existed approximately between 380 and 300 million years ago. Members of this family are noted for their peculiar dorsal fin.