xanthomonad vs eubacterium

xanthomonad and eubacterium both are nouns.

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

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

xanthomonad: bacteria producing yellow non-water-soluble pigments; some pathogenic for plants
eubacterium: a large group of bacteria having rigid cell walls; motile types have flagella

Other hypernyms of xanthomonad include eubacteria, true bacteria.

xanthomonad (noun)	eubacterium (noun)
bacteria producing yellow non-water-soluble pigments; some pathogenic for plants	a large group of bacteria having rigid cell walls; motile types have flagella