Ellora
From Memory Alpha, the free Star Trek reference
The Ellora were one of two primitive races, including the Tarlac, that were conquered by the Son'a in 2325. The Elloran heads were surrounded by a patterned bone plate. The female and male Ellora share the exact same look.
By 2375, both the Ellora and the Tarlac were fully integrated into the So'na society as indentured servants. (Star Trek: Insurrection)
