'Hollywood Houseboys' Transgender Star Domonique Newburn Brutally Murdered

A transgender reality star has been murdered ... and cops have a suspect.

According to the police report ... the badly beaten body of Domonique Newburn was found in her Fontana, CA apartment Tuesday afternoon. There were clear signs of a struggle inside the unit.

Domonique stars in a YouTube docu-reality series, "Hollywood Houseboys," that follows the lives of 4 gay friends.

Cops have a hot lead. A suspect was seen leaving the apartment in a Black 2004 Mercedes C240 sedan -- California license number 7AAY925. Apparently the car belonged to Domonique.

Cops believe the suspect knew Domonique -- and is in his 20s or early 30s, 5'8" and average build.