Unlike many genera that can be described by commonalities inherited exclusively from their common ancestor, the classification of a species as being in the genus
Loligo is not based on positive discrimination. The only positive distinction is not based on any form of inheritance and has to do with its Eastern Atlantic distribution. Other than this, the grounds for grouping a squid in this taxon is exclusively based on its lacking of characteristics that would put it in another taxon. Thus all squid in
Loligo have rhomboidal fins as adults, elongated mantles, fins whose length exceeds their breadth, and lack
photophores, but all other squid genera do as well. == Mating ==