myxobacteria vs eubacterium

myxobacteria and eubacterium both are nouns.

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

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

myxobacteria: bacteria that form colonies in self-produced slime; inhabit moist soils or decaying plant matter or animal waste
eubacterium: a large group of bacteria having rigid cell walls; motile types have flagella

Other hypernyms of myxobacteria include eubacteria, true bacteria.

myxobacteria (noun)	eubacterium (noun)
bacteria that form colonies in self-produced slime; inhabit moist soils or decaying plant matter or animal waste	a large group of bacteria having rigid cell walls; motile types have flagella