sphagnum vs moss

sphagnum and moss both are nouns.

Word	Noun	Adjective	Verb	Adverb
sphagnum	Yes	No	No	No
moss	Yes	No	No	No

As nouns, moss is a hypernym of sphagnum; that is, moss is a word with a broader meaning than sphagnum:

sphagnum: any of various pale or ashy mosses of the genus Sphagnum whose decomposed remains form peat
moss: tiny leafy-stemmed flowerless plants

sphagnum (noun)	moss (noun)
any of various pale or ashy mosses of the genus Sphagnum whose decomposed remains form peat	tiny leafy-stemmed flowerless plants