[Neoselachii] Compagno, 1977 - modern sharks and rays see Cohort Neoselachii Compagno, 1977
   Order Carcharhiniformes Compagno, 1973 - ground sharks
     Family Proscylliidae Fowler, 1941 - finback catsharks
       Genus Gollum L.J.V. Compagno, 1973 [monotypic]
         1 Gollum attenuatus (Garrick, 1954) - slender smooth-hound