|Octopus or Squid?|
Photo and Article by David Denning
The class Cephalopoda includes a great diversity of Molluscs, often with complex anatomy (such as high resolving power eyes with lenses) and with complex behavior. Our November unknown, Rossia pacifica, the stubby squid, is a small cephalopod belonging to the Family Sepiolidae, a group which includes the cuttlefish. Although less than 6 centimeters in length, Rossia is a fairly successful cephalopod -- it is quite abundant across a range that extends from Southern California around the North Pacific to Japan.
The stubby squid lives at depths that range from shallow waters down to 300 meters or more. We have collected them in dredges on muddy and sandy bottom sediments. We have kept specimens of Rossia for several weeks in cold saltwater aquariums at Bamfield Marine Station. They have also been kept at the Seattle Aquarium and the Vancouver Aquarium, where they are a great attraction as a contrast to the world's largest octopus, the Giant Pacific Octopus.
Rossia reproduction is a terminal sort of thing -- at least for the adults. Both male and female die after mating. Before she dies, the female lays about 40 or so eggs, usually in a clam shell on the ocean floor. The eggs hatch after about five months and the new animals live for only two years before they mate, and die. Adult Rossia feed on shrimp, which are usually abundant on their ocean floor home.