cryptophyte vs algae

cryptophyte and algae both are nouns.

Word	Noun	Adjective	Verb	Adverb
cryptophyte	Yes	No	No	No
algae	Yes	No	No	No

As nouns, algae is a hypernym of cryptophyte; that is, algae is a word with a broader meaning than cryptophyte:

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

Other hypernyms of cryptophyte include alga.

cryptophyte (noun)	algae (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