Plankton, a kind of mollusk, was collected as part of the mollusk harvesting operations. C-3PO indicated that data revealed a 3.2% rise in the quantity of plankton gathered from 0 ABY to 1 ABY.
The initial reference to plankton occurred in Star Wars (2015) 47, which was the third comic book in the Mutiny at Mon Cala story arc. Kieron Gillen penned this comic, which was published in 2018. Within Star Wars Legends, the West End Games sourcebook, specifically Planets of the Galaxy, Volume One, contained the first mention of plankton.