little club moss vs spike moss

little club moss and spike moss both are nouns.

Word	Noun	Adjective	Verb	Adverb
little club moss	Yes	No	No	No
spike moss	Yes	No	No	No

As nouns, little club moss and spike moss are synonyms defined as:

little club moss and spike moss: any of numerous fern allies of the genus Selaginella

Other synonyms of little club moss include spikemoss.

little club moss (noun)	spike moss (noun)
any of numerous fern allies of the genus Selaginella	any of numerous fern allies of the genus Selaginella