Fort Worth Transportation Authority is primarily a bus operation, but they partner with DART of Dallas in administering Trinity Railway Express commuter rail. They will have their second commuter rail property once TexRail opens (scheduled to happen by the end of this year 2018). From NBC Dallas/Fort Worth, 1/29/18:
The T Becomes Trinity Metro
Public transportation in the City of Fort Worth will be under a different name.
Monday, the Fort Worth Transit Authority voted to change the name of the transit program once known as "The T" to be known as "Trinity Metro."