Caribbean Reef Squid

Like most squid species, reef squid exhibit an asymmetric, horizontal pupil, commonly referred to as W-shaped. Its purpose is currently unknown, though research supports utilization in balancing light within their vision field. This creates evenly visualized images.

Another phenomenon, deemed the "half-and-half" body pattern, is a body morph that occurs during interactions with other cephalopods. One half of the cephalopod's body gets darker than the typical coloration a few minutes after the interaction occurs. This color-change is also observed during the sleeping state. The extended 'quiet state' results in a pale, uniform color compared to the shorter 'active state' including varying colors, textures, and patterns.

The Caribbean reef squid is found throughout the Caribbean Sea as well as off the coast of Florida, commonly in small schools of four to thirty in the shallows associated with reefs.

The habitat of the Reef Squid changes according to the squid's stage of life and size. New hatchlings tend to reside close to the shore in areas from 0.2 to 1 metre (1 to 3 ft) below the surface on or under vegetation. Young small squid typically congregate in shallow turtle grass near islands and remain several centimeters to two meters from the surface to avoid bird predators. Adults venture out into open water and can be found in depths up to 150 m. When mating, adults are found near coral reefs in depths of 1.5 to 8 metres (5 to 26 ft).

This species, like most squids, is a voracious eater and typically consumes 30–60% of its body weight daily. Prey is caught using the club-like end of the long tentacles which are then pulled towards the mouth supported by the shorter arms. Like other cephalopods, it has a strong beak which it uses to cut the prey into parts so that the raspy tongue, or radula, can be used to further process the food. It consumes small fish, other molluscs, and crustaceans.

Like other cephalopods, the Caribbean reef squid is semelparous, dying after reproducing. Females lay their eggs then die immediately after. The males, however, can fertilize many females in a short period of time before they die. Females lay the eggs in well-protected areas scattered around the reefs. After competing with 2-5 other males, the largest male approaches the female and gently strokes her with his tentacles. At first she may indicate her alarm by flashing a distinct pattern, but the male soon calms her by blowing water at her and jetting gently away. He returns repeatedly until the female accepts him, however the pair may continue this dance or courting for up to an hour. The male then attaches a sticky packet of sperm to the female's body. As he reaches out with the sperm packet, he displays a pulsating pattern.