Heterokontae vs class Heterokontae

Heterokontae and class Heterokontae both are nouns.

Word	Noun	Adjective	Verb	Adverb
Heterokontae	Yes	No	No	No
class Heterokontae	Yes	No	No	No

As nouns, Heterokontae and class Heterokontae are synonyms defined as:

Heterokontae and class Heterokontae: all the yellow-green algae having flagella of unequal length

Other synonyms of Heterokontae include Chrysophyceae, class Chrysophyceae.

Heterokontae (noun)	class Heterokontae (noun)
all the yellow-green algae having flagella of unequal length	all the yellow-green algae having flagella of unequal length