sturgeon vs ganoid fish

sturgeon and ganoid fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
sturgeon	Yes	No	No	No
ganoid fish	Yes	No	No	No

As nouns, ganoid fish is a hypernym of sturgeon; that is, ganoid fish is a word with a broader meaning than sturgeon:

sturgeon: large primitive fishes valued for their flesh and roe; widely distributed in the North Temperate Zone
ganoid fish: primitive fishes having thick bony scales with a shiny covering

Other hypernyms of sturgeon include ganoid.

sturgeon (noun)	ganoid fish (noun)
large primitive fishes valued for their flesh and roe; widely distributed in the North Temperate Zone	primitive fishes having thick bony scales with a shiny covering