Researchers first unearthed fossilized fragments of the ancient crocodile relative in 2009, but its bones remained encased in plaster and unidentified until recently.
In 2014, a student and mentor at Virginia Tech began analyzing the fossils.
The term same-sex relationship is not strictly related to the sexual orientation of the participants.
During the Triassic period, the four-legged creatures dwarfed most other species, stretching 12 to 18 feet long.
"These were some of the biggest predators at the time, all dinosaurs were much smaller," said Sterling Nesbitt, an assistant professor of geosciences at Virginia Tech who aided Lessner's work.
The new species is named and described in a paper published this week in the journal Peer J.
A same-sex relationship is a relationship between persons of the same sex and can take many forms, from romantic and sexual, to non-romantic homosocially-close relationships.
The term is primarily associated with gay and lesbian relationships.
"Initially, I cleaned fossils in the lab and worked on a project reconstructing soft tissue structures using computed tomographic, or CT, scans on the computer," undergraduate researcher Emily Lessner, now a senior, said in a news release.
"I began looking at Vivaron pretty soon after." Lessner's work revealed jaw bones, skull fragments and hip-bones from three individuals, including two adults and one juvenile.