Uroteuthis noctiluca, commonly known as the luminous bay squid, is a species of squid native to shallow water on the eastern coast of Australia. It uses a pair of luminous organs to camouflage itself from predators at night.

Description In this species, females grow larger than males. The maximum mantle length is about 90 mm (3.5 in), the width of the mantle being about 30% of the length. The fins are rounded and the posterior of the mantle is heart-shaped. The eight arms are short and there are rings of suckers on each arm, each sucker having four to seven teeth. The male has the fourth left arm hectocotylised over its entire length. The two tentacles are short and robust, with broad paddle-shaped clubs. There are two photophores on the underside of the ink sac. Populations in the north of the range differ from those in the south in the arrangement of the suckers on the male's right ventral arms.