proboscidian vs proboscidean

proboscidian and proboscidean both are nouns.

Word	Noun	Adjective	Verb	Adverb
proboscidian	Yes	No	No	No
proboscidean	Yes	No	No	No

As nouns, proboscidian and proboscidean are synonyms defined as:

proboscidian and proboscidean: massive herbivorous mammals having tusks and a long trunk

proboscidian (noun)	proboscidean (noun)
massive herbivorous mammals having tusks and a long trunk	massive herbivorous mammals having tusks and a long trunk