CephalopodsCephalopoda

Cephalopods are a group of molluscs characterized by a distinct head, large complex eyes, and a ring of eight sucker-lined arms surrounding the mouth. Squids and cuttlefish also possess a pair of longer, retractable feeding tentacles. Their body forms vary from the sac-like, eight-armed octopuses to the more elongated, finned squids and flattened, oval-bodied cuttlefish. They move primarily through jet propulsion using a muscular siphon, which also expels ink. Most species are capable of rapid changes in skin colour and texture, used for camouflage and communication. Body sizes range from a few centimetres to 1 metre (3.3 feet) in total length for some squid species.

As agile predators, cephalopods inhabit diverse marine environments, including reef crests, slopes, sandy bottoms, and open water, from shallow depths to below 200 metres (650 feet) on deeper slopes. They can be found hidden in rock crevices or hovering actively in the water column. Their diet primarily consists of crustaceans, fish, and other molluscs, which they capture using their arms and tentacles. When threatened, most species expel a cloud of dark ink to evade predators. Divers commonly encounter various species both during the day and on night dives.