squid vs loligo

squid and loligo both are nouns.

Word	Noun	Adjective	Verb	Adverb
squid	Yes	No	No	No
loligo	Yes	No	No	No

As nouns, loligo is a hyponym of squid; that is, loligo is a word with a more specific, narrower meaning than squid:

squid: widely distributed fast-moving ten-armed cephalopod mollusk having a long tapered body with triangular tail fins
loligo: somewhat flattened cylindrical squid

Other hyponyms of squid include ommastrephes, architeuthis, giant squid.

squid (noun)	loligo (noun)
widely distributed fast-moving ten-armed cephalopod mollusk having a long tapered body with triangular tail fins	somewhat flattened cylindrical squid
(Italian cuisine) squid prepared as food