Colubrid and Grass snake

Colubrid noun - Mostly harmless temperate-to-tropical terrestrial or arboreal or aquatic snakes.

Grass snake and colubrid are semantically related. In some cases you can replace phrase "Grass snake" with "Colubrid", this terms are similar.

Grass snake noun - Any of numerous nonvenomous longitudinally-striped viviparous North American and Central American snakes.

Colubrid and grass snake are semantically related. You can use "Colubrid" instead a noun phrase "Grass snake".