Calyx was a Cardassian male, the martial docent at the Bamarren Institute for State Intelligence.

Calyx was a gnarled old man with one glass eye, it was rumored amongst the students that he had been a Gul but was demoted due to his insistence for fighting alongside his men rather than taking a privileged back seat.

Calyx is in fact the mans nick name amongst the students, a Calyx in Cardassian mythos is the name of an energetic multilimbed creature. Calyx reflected this in his mastery of Strategems - Cardassian physical and mental combat moves where each part of the body works independently. (DS9 Novel: A Stitch in Time)