The bigfin reef squid, Sepioteuthis lessoniana, is a warm water species ranging throughout the tropical Indo-Pacific from Hawaii to the Red Sea.
These squid typically inhabit shallow waters near shore lines, and look rather like cuttlefish due to the large fin that runs along their mantle or dorsal body wall.
Like many other cephalopods, reef squid can change their skin colors and markings rapidly, and use these displays to attract mates, warn off rivals, and for camouflage.
This species exhibits elaborate courtship displays, with individuals swimming in synchrony for extended periods. The female attaches her eggs to a substrate such as rocks or plants, laying them in single strands.
The Lembeh Strait in North Sulawesi is famous for its unusually high marine biodiversity, particularly of unusual animals that live on the exposed sand areas.
Watch this video of a night dive at the Lembeh Strait to see some of these animals, including bigfin reef squid.