Description
Pygmy killer whales reach a length of about 8-9 feet (2.4-2.7 m). They are usually relatively slender-bodied with a rounded head, an underslung jaw, and no beak.
The falcate dorsal fin, located about the center of the back, is usually between 8 and 12 inches (20.3 and 30.1 cm) tall (though it may reach 15 inches [38 cm] in some individuals), is sometimes very distinctive, and resembles that of the Atlantic bottlenosed dolphin. The flippers are slightly rounded on the tips.
The color has been described as dark gray or black on the back, often lighter on the sides, extending higher in front of the dorsal fin and with a small zone of white on the underside, often a lighter gray area on the sides, and distinctive white regions around the lips. The chin may be completely white. This white zone on the chin, described as a "goatee," is often clearly visible in swimming animals.
May Be Confused With
The pygmy killer whale resembles the false killer whale but is much smaller and can be distinguished at close range by the zones of white coloration. False killer whales are almost all black and reach a length of up to at least 18 feet (5.5 m). Pygmy killer whales are dark gray on the back, often lighter on the sides, and show a region of white on the belly which may extend so high up onto the sides that it is visible on a swimming animal. Further, they reach only 8-9 feet (2.4-2.7 m).
Pygmy killer whales may also be confused with the similarly sized and colored many-toothed blackfish. So little is known of the two species' appearance and behavior at sea that it is doubtful that they can be successfully distinguished, though many-toothed blackfish apparently lack the white region often seen on the sides of pygmy killer whales. Further, pygmy killer whales have rounded flippers and smoothly tapered heads, while those of the many-toothed blackfish are pointed on the tip and more sharply pointed (often described as a parrot beak).
Distribution
Pygmy killer whales are probably distributed in the tropical and subtropical waters of the western North Atlantic. They have been reported from Texas, the Atlantic coast of Florida, and St. Vincent Island, Lesser Antilles. Records of the species from the other oceans of the world suggest that its distribution is limited to tropical and subtropical waters.