class Pteridospermopsida vs Pteridospermopsida

class Pteridospermopsida and Pteridospermopsida both are nouns.

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

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

class Pteridospermopsida and Pteridospermopsida: extinct gymnosperms most of Carboniferous to Jurassic: seed ferns and allies

class Pteridospermopsida (noun)	Pteridospermopsida (noun)
extinct gymnosperms most of Carboniferous to Jurassic: seed ferns and allies	extinct gymnosperms most of Carboniferous to Jurassic: seed ferns and allies