Desmond was a bartender at Beaches restaurant in Manhattan Beach.
A public defender was appointed to represent Perez.
The brief arraignment was continued to October 23.
Desmond was last seen alive during the early morning of February 15 at Bac Street Lounge in Redondo Beach.
Investigators say Perez did not know Desmond, but he tried to pick her up as she walked home from the bar to sexually assault her.
Her body was later discovered by a driver along Highway 330 in Running Springs in the San Bernardino Mountains.
Deputies arrested Perez last week after receiving an anonymous tip.
The cause of death has not been disclosed.