Ophidians (Ultima Online)

Ophidians are snake-like, swamp-dwelling creature that populate The Lost Lands, which appeared for the first time in Ultima Online: The Second Age. They look like some sort of hybrid between man and snake. They are sworn enemies to the Terathans.

In Ultima X
Ophidians were meant to be included in the cancelled Ultima X. See Ultima X Ophidian for details. 

Trivia

 * While any relation to the Ophidians of Serpent Isle is not clearly stated, they appear to be similar to the Naga that can be found in that isle.