Euteleostomi is a successful clade that includes more than 90% of the living species of vertebrates. Euteleostomes are also known as "bony vertebrates". Both major subgroups are successful today: Actinopterygii includes the majority of extant fish species, and Sarcopterygii includes the tetrapods. This clade is sometimes called "Osteichthyes", but since that name literally means "bony fish" and traditionally is a paraphyletic group that excludes tetrapods, the name Euteleostomi was coined as a substitute.