Orthacodontidae

Orthacodontidae (also spelled Orthacodidae^[1]) is an extinct family of sharks. It is disputed as to whether it belongs to the modern shark order Hexanchiformes,^[2] or the extinct order Synechodontiformes.^[3] It contains three genera. Some other authors included it in Lamniformes.^[4] More recent studies have generally favored its placement in the Hexanchiformes.^[1]

Orthacodontidae Temporal range: Early Jurassic–Paleocene PreꞒ Ꞓ O S D C P T J K Pg N
Head of Archaeogracilidens macer
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Subclass:	Elasmobranchii
Family:	†Orthacodontidae Glikman, 1957
Genera
Archaeogracilidens Villalobos-Segura et al. 2025 Occitanodus Guinot, Cappetta & Adnet, 2014 Sphenodus Agassiz, 1843

Species

• Archaeogracilidens Villalobos-Segura et al. 2025
  • Archaeogracilidens macer (Quenstedt, 1852)
• Occitanodus Guinot, Cappetta & Adnet, 2014
  • Occitanodus sudrei Guinot, Cappetta & Adnet, 2014
• Sphenodus Agassiz, 1843 (Nomen dubium)^[1]
  • Sphenodus alpinus Gümbel, 1861
  • Sphenodus longidens Agassiz, 1843
  • Sphenodus lundgreni Davis, 1890
  • Sphenodus planus Agassiz, 1843
  • Sphenodus rectidens Emmons, 1858
  • Sphenodus robustidens Seguenza, 1900
  • Sphenodus tithonius Gemmellaro, 1871
  • Sphenodus virgai Gemmellaro, 1871