historically, several species were recognised, typically C. tropicus and C. hyodon for North and South American remains, respectively, but recent scholarship suggests that there is only a single valid species, C. hyodon.
Historically, various species were identified, typically *C. tropicus* and *C. hyodon* for North and South American remains, respectively, but recent research suggests that there is only a single valid species, *C. hyodon*.