This is a regular verb with a spelling change. It follows the conjugation pattern of the verb vivir.
Spelling Change: guo go - gua ga - guá gá
PresentPresente
No distingo a los gemelos.
I can't tell the twins apart.
PreteritePretérito indefinido
Distinguió una luz a lo lejos.
He made out a light in the distance.
Present SubjunctivePresente de subjuntivo
Es importante que los niños distingan el bien del mal.
It's important that children can tell right from wrong.