tlilcoatl. biuora negra. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 147v. col. 2. Thanks to Joe Campbell for providing the transcription.
Frances Karttunen:
TLĪLCŌĀ-TL a type of black snake / culebra carbonera (Z) [(2)Zp.37,223]. See TLĪL-LI, CŌĀ-TL. Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 308.