Testudines vs Chelonia

Testudines and Chelonia both are nouns.

Word	Noun	Adjective	Verb	Adverb
Testudines	Yes	No	No	No
Chelonia	Yes	No	No	No

As nouns, Testudines and Chelonia are synonyms defined as:

Other synonyms of Testudines include order Chelonia, order Testudinata, order Testudines, Testudinata.

Testudines (noun)	Chelonia (noun)
tortoises and turtles	tortoises and turtles
	green turtles