"I'm deeply saddened at the news of my dear friend Lupe Ontiveros passing," Longoria, 37, who appeared on ABC's series opposite Ontiveros from 2004 until the end of its run in May 2012, said via Twitter. "She was more than a colleague to me, she was my family. My heart is with your family Lupe."
"I am tremendously saddened by the news of Lupe's passing! I've enjoyed her work throughout the years," Lopez, 42, told Us Weekly in a statement. "She was a great actress and working with her in Selena was an unforgettable experience. She will truly be missed."
Ontiveros is survived by her husband and three adult children.