Its head is distinctly wider than its neck and it has large bulging eyes with reddish irises and light brown elliptical pupils.

Developing snakes are nourished by a yolk sac for 79 to 90 days at which time they break through the outer shell using an egg tooth.

Young northern cat-eyed snakes appear identical to adults but feature much fresher coloration.

[8][9] The northern cat eye is found in North America: US (S Texas), Mexico (Chiapas, Nuevo León, Quéretaro, Oaxaca, Puebla, Coahuila, Jalisco, Campeche, Yucatán, Quintana Roo, Nayarit), Guatemala, Honduras, Belize, El Salvador, Nicaragua, and Costa Rica.

[10] Within Costa Rica it is found on both Caribbean and Pacific coasts, including in Golfo Dulce, up to 1,200 m (3,900 ft) above sea level in a wide variety of habitats but most common at edges of ponds where amphibians breed.