flowering fern vs Helminthostachys zeylanica

flowering fern and Helminthostachys zeylanica both are nouns.

Word	Noun	Adjective	Verb	Adverb
flowering fern	Yes	No	No	No
Helminthostachys zeylanica	Yes	No	No	No

As nouns, flowering fern and Helminthostachys zeylanica are synonyms defined as:

flowering fern and Helminthostachys zeylanica: Australasian fern with clusters of sporangia on stems of fertile fronds

flowering fern (noun)	Helminthostachys zeylanica (noun)
any fern of the genus Osmunda: large ferns with creeping rhizomes; naked sporangia are on modified fronds that resemble flower clusters	Australasian fern with clusters of sporangia on stems of fertile fronds
Australasian fern with clusters of sporangia on stems of fertile fronds