alderfly vs Sialis lutaria

alderfly and Sialis lutaria both are nouns.

Word	Noun	Adjective	Verb	Adverb
alderfly	Yes	No	No	No
Sialis lutaria	Yes	No	No	No

As nouns, alderfly and Sialis lutaria are synonyms defined as:

alderfly and Sialis lutaria: dark-colored insect having predaceous aquatic larvae

Other synonyms of alderfly include alder fly.

alderfly (noun)	Sialis lutaria (noun)
dark-colored insect having predaceous aquatic larvae	dark-colored insect having predaceous aquatic larvae