(Gray, 1850) - Clymene dolphin
Distinctive Characteristics
The clymene dolphin is externally similar to the spinner dolphin, but is smaller and more robust, with a much shorter and stockier beak. The dorsal fin is slightly more falcate, as opposed to the often very triangular dorsal fins of spinner dolphins. Despite these external similarities with the spinner dolphin, skull morphology indicates that the clymene dolphin may be closely related to the striped dolphin.
A three-part colour pattern, with a dark grey cape, light grey sides, and white belly, is characteristic of this species. The cape dips in 2 places, above the eye, and below the dorsal fin. The beak is mostly light grey, but the lips and beak tip are black. There is also a dark stripe on the top of the beak, from the tip to the apex of the melon, and often a dark “moustache” marking on the middle of the top of the beak. The eye is also surrounded by black, and a dark grey stripe runs from the eye to the flipper.
Tooth counts are generally much lower than in spinner dolphins: 38 to 49 teeth per row. They are slender and pointed.
Can be confused with
Clymene dolphins are most easily confused with spinner dolphins, but are more robust, with shorter stubbier beaks. Also, the colour pattern is slightly different; the 2 dips in the cape and the dark line (and often a “moustache”) on top of the beak will allow clymene dolphins to be distinguished. The body shape of clymene dolphins also closely resembles that of short-beaked (offshore) forms of the common dolphin, as does the colour pattern in a superficial way. Common dolphins can best be distinguished by their hourglass pattern, cape that forms a V below the dorsal fin, chin-to-flipper stripe, and absence of a “moustache.”
Size
So far, clymene dolphins are known to reach at least 2.0 m in length and sexual maturity is reached by about 1.8 m. Newborn length is unknown, but is less than 1.2 m. This species reaches weights of at least 85 kg.
Geographical Distribution
The clymene dolphin is found only in the tropical and subtropical Atlantic Ocean, including the Caribbean Sea and Gulf of Mexico. There are records as far north as New Jersey on the U.S. east coast and as far south as southern Brazil. The limits on the West African coast are not well known. This is a deep water oceanic species, not normally seen near shore.
Biology and Behaviour
Very little is known of the clymene dolphin's natural history. Schools tend to be much smaller than those of spinner dolphins (generally less than 50 animals). They are known to associate with other species of dolphins. These quick and agile dolphins ride bow waves, and have been reported to spin on the long axis.
Clymene dolphins feed on small fish and squid at moderate depths, presumably mainly at night.
Exploitation
In the Caribbean, clymene dolphins appear, at least occasionally, to be taken in the Lesser Antilles small cetacean fishery, and in gillnets. They may be one of the species taken in tuna purse seines in the eastern tropical Atlantic.
IUCN Status
Insufficiently known.