cryptomonad vs alga

cryptomonad and alga both are nouns.

Word	Noun	Adjective	Verb	Adverb
cryptomonad	Yes	No	No	No
alga	Yes	No	No	No

As nouns, alga is a hypernym of cryptomonad; that is, alga is a word with a broader meaning than cryptomonad:

cryptomonad: common in fresh and salt water appearing along the shore as algal blooms
alga: primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves

Other hypernyms of cryptomonad include algae.

cryptomonad (noun)	alga (noun)
common in fresh and salt water appearing along the shore as algal blooms	primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves