Now don’t let the name fool you, swamp eels are freshwater fish (ត្រីឆ្លូញ) with an appearance that resembles eels. Adult swamp eels have no fins, and that is why many people mistake them for actual eels. However, larvae have large pectoral fins that they use to fan water over their bodies. I am going to show you 6 swamp eel species in Cambodia, and all of them are able to breathe air. Let’s take a look at the list below to find out what they are.
Bar-Bellied Spiny Eel (ត្រីឆ្លូញបង្កង់)
Scientific Name: Macrognathus Circumcinctus
This is probably what we call them here but bar-bellied spiny eel has a more common name as half-banded spiny eel. A bar-bellied spiny eel has a maximum length of 28.6 centimeters, with a flattened gray body. The unique feature that this swamp eel species has is the series of regular oblique dark bars on its body. Each bar has a narrow extension that extends either partially or entirely across the abdomen. Bar-bellied spiny eels occur in peats or streams around flooded fields and large rivers. There is not a lot of information about this eel, and that’s all I could find.
Eyespot Spiny Eel (ត្រីឆ្លូញកែវ)
Scientific Name: Macrognathus Aculeatus
Here you are looking at a pretty spiny eel species with an appealing appearance. An eyespot spiny eel is usually around 12 to 15 centimeters long but there are also 20-centimeters individuals. Eyespot spiny eel aka lesser spiny eel has a yellow upper body with a black line down the middle and lower body. The unique part is the numerous small spines and prominent eyespots on the dorsal fin. This swamp eel species has a wide distribution across South and Southeast Asia, living in medium to large rivers. They also inhabit flooded fields with dense vegetation and sandy bottoms as well. These eels have a big appetite, feeding on anything they can chomp on such as mosquito larvae, small fish, and more.
Fire Spiny Eel (ត្រីខ្ជឹងផ្កា)
Scientific Name: Mastacembelus Erythrotaenia
One of the easiest things to recognize about this swamp eel species is its elongated body and distinctive pointed snout. The body of the eel has dark brown or gray with a lighter belly along with several bright lateral stripes and spots; hence the name. A fire eel can reach up to a length of 1 meter and its coloration makes it one of a kind. Native to Southeast Asia, this eel-like fish is also quite common in the aquarium trade due to its appearance. These bottom-dwellers inhabit the muddy bottom of flood plains and slow-moving rivers feeding on crustaceans, fish, insect larvae, plant matter, and worms. Sadly, overfishing causes the population of the fire spiny eel to decline in parts of Cambodia and Thailand.
Frecklefin Eel (ត្រីឆ្លូញ)
Scientific Name: Macrognathus Maculatus
Frecklefin eels are one of the most common swamp eel species that people eat in Southeast Asia. Meanwhile, many hobbyists love having them in aquariums due to their peaceful appearance. It can grow up to 28 centimeters, and its elongated body is dark brown in color. This eel mainly inhabits shaded streams in freshwater swamp forests, lowland forests, and peat swamps. It likes to hide under sunken leaf litter and other debris during the day, and it only hunts at night. The frecklefin eels feed on benthic invertebrates such as aquatic worms, insect larvae, and small crustaceans.
Peacock Eel (ត្រីឆ្លូញក្ងោក)
Scientific Name: Macrognathus Siamensis
A peacock eel can grow up to 30 centimeters long, and it has a tan body with a yellow stripe running across it. The most distinctive feature that this eel species possesses is the 5 eyespots at its caudal and dorsal fins. Those eyespots resemble that of a peacock, and that is how it got its name. Peacock eels are residents of freshwater habitats in Southeast Asia, native to the Chao Phraya and Mekong basins. They inhabit slow-moving backwaters with muddy or sandy bottoms where they can bury in like canals, ponds, and swamps. Similar to other swamp eel species out there, this one also feeds on annelids, crustaceans, and fish.
Tire-Track Spiny Eel (ត្រីខ្ជឹង)
Scientific Name: Mastacembelus Armatus
The tire-track eel or zigzag eel is a swamp eel species with brown circular patterns and zigzag lines. It has a snake-like body without pelvic fins, and the body is dull brown with a dark beige back. The eel can grow up to 91 centimeters, and its unique appearance makes it quite popular in the aquarium. At the same time, it also has a docile nature so it can be in the same tank with other fishes. As long as the tank mates are not its own kind or smaller fish species, they are good to go.
With a wide range, the tire-track eel lives in a variety of habitats such as coastal marshes and lowland wetlands. It is also common to find them in highland streams, rivers with rocky or sandy riverbeds, and still waters. During the flood season, these eels will dwell in canals, lakes, and other floodplain areas. They hide under rocky bottoms or sand during the day, and they only come out to hunt and night. In their habitats, the zigzag eels feed on crustaceans, insects, insect larvae, and various worm species they can find.
Related Post: Eel Species In Cambodia