Xenocongrid eel
The Xenocongrid eel is a tropical marine eel found in the Pacific Ocean, commonly known as a false moray eel due to its relation to true moray eels. This family of eels typically inhabits shallow coastal waters, particularly around coral reefs and rocky shorelines, with some species venturing deeper, ranging from 265 to 1,200 feet below the surface. The known species within the Xenocongrid genus include the false moray eel, collared eel, and bicolor eel, each measuring between 6 to 10 inches long. Characterized by their small size and dull coloration, these eels possess flattened heads and well-developed pectoral fins in some species, while their bodies feature long dorsal fins that merge with their caudal and anal fins.
Xenocongrid eels lack the lateral line sensors that many other eel species have, instead possessing a few branchial pores and tiny sensors on their chins to detect movement and food. Their diet is thought to consist mainly of crustaceans and other small marine organisms, although specific dietary habits remain uncertain. These eels are believed to spawn in large groups in deep offshore waters, with their young hatching into a larval form known as leptocephali, which undergo a metamorphosis into their adult shape. Currently, the Xenocongrid eel is not considered threatened, and much about their life cycle and reproductive behavior remains unknown.
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Xenocongrid eel
The xenocongrid eel is a tropical marine eel native to the Pacific Ocean. Eels in this family are often called false moray eels because they are related to the moray eels. These species are small, dull- colored, and usually live in shallow coastal waters.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Anguilliformes
Family: Chlopsidae
Genus: Chilorhinus
Species: Platyrhynchus
These representatives of the xenocongrid eels all live in the warm coastal waters of the Indo-Pacific Ocean. While the false moray eel and collared eel prefer the coral reefs and rocky shorelines, the bicolor eel generally swims between 265 and 1,200 feet (80 and 360 meters) below the surface.
Xenocongrid eels such as these are related to the moray eels and may sometimes be mistaken for the true morays, giving them the name false morays. They are small and dull-colored eels. These three species are between 6 and 10 inches (15 to 25 centimeters) long. The false moray eel is the largest of the three at 10 inches (25 centimeters), and the collared eel is only around six inches (15 centimeters) long. The bicolor eel may reach a maximum length of eight inches (20 centimeters). They have flattened heads and fleshy snouts.
Eels in this family, including these three, are dull-colored. The name bicolor, meaning two-colored, refers to the two colors of the bicolor eel's slender body. It is brown above and light- colored on its underside. The false moray eel has tan or brown skin, while the collared eel is dark bluish gray to purplish brown and has a cream-colored collar around its neck.
The pectoral fins of the false moray and collared eels are well-developed, while the bicolor eel does not have any. All three have long dorsal (back) fins which join with their caudal (tail) and anal (rear) fins in one long, feather-like fin around their bodies. The gill openings behind their heads are small and rounded.
Unlike many other eel species, xenocongrid eels do not have lateral line sensors on their bodies. Many eel species have a line of pores, or tiny openings, running along both sides of their bodies and heads. These pores are sensitive to motion and pressure and help the eels detect these things from a distance. Xenocongrid eels have one or two branchial pores which function in somewhat the same manner as the lateral line pores.
Many species in this family, including the false moray, have a number of tiny hair-like sensors on their chins which help them detect movement and food. The diet of these eels is uncertain, but it may likely be crustaceans and other small marine, or ocean, organisms.
Very little else is known of these and other xenocongrid eels, including their life spans and reproductive habits. It is thought that all species in this family spawn in large groups in deep offshore waters. Like other eels, the young eels hatch from eggs into a larval stage called leptocephali. Each leptocephalus looks like a transparent, or clear, willow leaf and not like an eel. The duration of this stage is not known for these species as it is for others, which may remain leptocephali for one to two years. The leptocephali metamorphose, or change, into the adult eel-like form and gain color. The xenocongrid eel is not considered a threatened species.
Bibliography
“Chlopsidae - False Morays - Wildlife Journal Junior.” New Hampshire PBS, 2023, nhpbs.org/wild/Chlopsidae.asp. Accessed 16 Mar. 2024.