myxobacterium vs eubacteria

myxobacterium and eubacteria both are nouns.

Word	Noun	Adjective	Verb	Adverb
myxobacterium	Yes	No	No	No
eubacteria	Yes	No	No	No

As nouns, eubacteria is a hypernym of myxobacterium; that is, eubacteria is a word with a broader meaning than myxobacterium:

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

Other hypernyms of myxobacterium include eubacterium, true bacteria.

myxobacterium (noun)	eubacteria (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