clostridia vs eubacterium

clostridia and eubacterium both are nouns.

Word	Noun	Adjective	Verb	Adverb
clostridia	Yes	No	No	No
eubacterium	Yes	No	No	No

As nouns, eubacterium is a hypernym of clostridia; that is, eubacterium is a word with a broader meaning than clostridia:

clostridia: spindle-shaped bacterial cell especially one swollen at the center by an endospore
eubacterium: a large group of bacteria having rigid cell walls; motile types have flagella

Other hypernyms of clostridia include eubacteria, true bacteria.

clostridia (noun)	eubacterium (noun)
spindle-shaped bacterial cell especially one swollen at the center by an endospore	a large group of bacteria having rigid cell walls; motile types have flagella