Triexians were a long-lived species, with lifespans stretching to centuries. Elder Triexians lapsed into a death-like state every twenty-five years, then molted their skins and re-emerged in what was called the Rebirth. Many Triexians served in Starfleet over the years, including Lieutenant Arex Na Eth. (NF - Gateways novel: Cold Wars; NF - No Limits short story: "The Road to Edos")