Its petals are golden yellow with varying degrees of white crenulations in the lip.

It has been referred to for generations as costicoatzontecoxòchitl, meaning "flower in the form of yellow serpent head", by the Nahuas (indigenous peoples of southwestern United States and northwestern Mexico).

Its lip is more or less the same length, with darker veins and ruffled texture, united with the column at the base.

The ovaries are free of any sharp angles or wings, while its pods are rounded and ribbed.

P. citrina grows on trees in mixed oak-pine forests in central and southern Mexico.