Sapphire eel
The sapphire eel, also known as the Guayana pike-conger or pike-headed eel, is a striking species recognized for its deep blue metallic sheen against a black-gray body. This eel belongs to the family Muraenesocidae and is one of 15 species in the pike conger group, showcasing distinct skeletal features compared to the Congridae family. Typically growing to an average length of about 20 inches (50 centimeters), some individuals can reach up to 78 3/4 inches (200 centimeters). Sapphire eels inhabit the western Atlantic Ocean, particularly along the coasts of Brazil, Cuba, and Caribbean islands, thriving in brackish waters of bays and estuaries up to depths of 330 feet (100 meters).
Equipped with a large mouth and conical teeth, they are skilled predators, feeding on bony fish, shrimp, crabs, and cephalopods. Notably, their blood contains a toxin that can be harmful if it comes into contact with human mucous membranes, although this risk is mitigated when the eel is cooked. The reproductive process involves the female releasing eggs into the ocean, which the male fertilizes, leading to the development of larvae called leptocephali. While the duration of their larval stage and overall lifespan remains uncertain, the sapphire eel exemplifies the diverse adaptations and ecological roles of eel species in marine environments.
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Sapphire eel
The sapphire eel receives its name from the deep blue metallic sheen of its black-gray skin. It is also called the Guayana pike-conger and the pike-headed eel.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Anguilliformes
Family: Muraenesocidae
Genus: Cynoponticus
Species: Savanna
The sapphire eel is one of 15 pike conger species in the Muraenesocidae family, which is similar to the Congridae family except for features of their skeletons. Its name comes from the deep blue metallic shine of the black-gray skin on its back and broad, flat, slab-like sides. The forward part of its underside is silver as if it had a silver chest.
The dorsal, or back, fin begins just in front of the pectoral fins, runs down its back, and joins its caudal and anal, or tail and rear, fins. It then continues forward and ends at the point where the silver patch on its underside ends. It has a pair of well-developed pectoral fins behind its head which help it swim.
An average full-grown sapphire eel is around 20 inches (50 centimeters), though some grow much longer. The largest recorded sapphire eel measured 78 3/4 inches (200 centimeters).
This eel species lives in the western Atlantic Ocean on the coast of Brazil, Cuba, and the Caribbean islands. Eel blood contains a poison, and humans must be careful when handling the eels. The blood can cause sickness if it comes in contact with a person's eyes or a mucous membrane. This poison is destroyed when the flesh is cooked.
Bays and estuaries from the surface to depths of 55 fathoms, or 330 feet (100 meters), are the home of the sapphire eel. Estuaries are places where freshwater rivers flow into bodies of saltwater and the waters mix. The water, called brackish water, is no longer fresh but also is not as salty as the ocean water surrounding it. It has a large mouth and several rows of strong, conical teeth. It preys on bony fish, shrimp, crabs, octopuses, squid, and cuttlefish.
Like other eels, the life cycle of the sapphire eel begins when the male and female spawn in the ocean. The female releases a large number of eggs into the water which the male then fertilizes. When they hatch, the eel larvae are called leptocephali. A leptocephalus looks like a slender, clear willow leaf instead of having a long, stretched body like an adult. Some species of eels remain in this stage for one to two years. Information on how long it takes the sapphire eel to metamorphose, or change, into an adult is unavailable. At some point, it does change into a small form of its parents and gains color.
The life span of the sapphire eel has not been determined.
Bibliography
"Cynoponticus Savanna (Bancroft, 1831)." Fish Base, fishbase.mnhn.fr/summary/SpeciesSummary.php?ID=1096&AT=Sapphire+eel. Accessed 15 Apr. 2024.
"Species: Cynoponticus Savanna, Guayana Pike-conger." Smithsonian Tropical Research Institute, biogeodb.stri.si.edu/caribbean/en/thefishes/species/2898. Accessed 15 Apr. 2024.