mealworm vs larva

mealworm and larva both are nouns.

Word	Noun	Adjective	Verb	Adverb
mealworm	Yes	No	No	No
larva	Yes	No	No	No

As nouns, larva is a hypernym of mealworm; that is, larva is a word with a broader meaning than mealworm:

mealworm: the larva of beetles of the family Tenebrionidae
larva: the immature free-living form of most invertebrates and amphibians and fish which at hatching from the egg is fundamentally unlike its parent and must metamorphose

mealworm (noun)	larva (noun)
the larva of beetles of the family Tenebrionidae	the immature free-living form of most invertebrates and amphibians and fish which at hatching from the egg is fundamentally unlike its parent and must metamorphose