(Kogia breviceps), an aquatic mammal of the suborder Odontoceti (toothed whales). It measures up to 4 m long and weighs up to 500 kg. The head is rounded; over the upper section there is a tall forehead projection (a fatty cushion). The mouth is located on the lower side of the head. There are one or two pairs of teeth in the upper jaw (they fall out as the animal approaches old age) and eight to 15 pairs in the lower jaw. The back and sides are dark in color, and the underparts are light. The pectoral fins are short, broad, and pointed; the dorsal fin is shaped like a sickle.
The pygmy sperm whale lives in the tropical and subtropical belts of the oceans. In the USSR it is found only near the southern islands of the Kuril Ridge. The animal feeds on cephalopods, deep-sea fish, crabs, and shrimp. The young are born in the spring and measure 1 to 1.2 m long and weigh 16 kg. The pygmy sperm whale is very rare and has not been adequately studied.