An interphasic species was a classification in comparative xenobiology.
In 2370, a number of parasitic interphasic organisms native to Thanatos VII came aboard the USS Enterprise-D through a new warp plasma conduit manufactured on that world. (TNG: "Phantasms")
In 2376, Mezoti speculated that the mysterious stowaway in Neelix's ghost story might be an interphasic species. (VOY: "The Haunting of Deck Twelve")