Pterynotus was named by Swainson (1833) [Sepkoski's age data: T Than R Sepkoski's reference number: 700]. It is extant. Its type is Murex pinnatus.

It was reranked as Murex (Pterynotus) by Dall (1890); it was misspelled as Pteronotus by Finlay (1929), Vokes (1970), Ladd (1977), Ladd (1982), Vaught et al. (1989), Beu et al. (1990), Wilson (1994), Squires and Goedert (1995), Squires (2001), Todd (2001), Wienrich (2001), Sepkoski (2002) and Landau et al. (2007).

It was assigned to Murex by Dall (1890); to Gastropoda by Finlay (1929); to Muricinae by Vaught et al. (1989), Beu et al. (1990), Wilson (1994) and Squires and Goedert (1995); to Neogastropoda by Sepkoski (2002); and to Muricidae by Vokes (1970), Ladd (1977), Ladd (1982), Squires (2001), Todd (2001), Wienrich (2001) and Landau et al. (2007).