catarrhinian vs catarrhine

catarrhinian is not a noun while catarrhine is a noun.

Word	Noun	Adjective	Verb	Adverb
catarrhinian	No	Yes	No	No
catarrhine	Yes	Yes	No	No

As adjectives, catarrhinian and catarrhine are synonyms defined as:

catarrhinian and catarrhine: of or related to Old World monkeys that have nostrils together and opening downward

catarrhinian (noun)	catarrhine (noun)
	of Africa or Arabia or Asia; having nonprehensile tails and nostrils close together

catarrhinian (adjective)	catarrhine (adjective)
of or related to Old World monkeys that have nostrils together and opening downward	of or related to Old World monkeys that have nostrils together and opening downward