Are Eels Snakes or Fish? Here’s the Scientific Answer
Fundacion Rapala – Eels often confuse people because of their snake-like bodies. At first glance, many wonder: are eels part of the snake family, or are they fish? The scientific answer is clear—eels are fish, not reptiles.
Habitat: Where Do Eels Live?
Although eels look similar to snakes, their habitat sets them apart. Eells spend their entire lives in shallow freshwater areas such as rice fields, swamps, and rivers. Snakes, meanwhile, can thrive not only in rice paddies but also in grasslands and trees. Unlike snakes, eels cannot survive outside of water.
Scientific Classification of Eels
According to zoological studies, eels belong to the class Pisces, meaning they are vertebrates (animals with backbones) that breathe using gills. This firmly places them in the fish category. Snakes, in contrast, are reptiles.
Here’s the scientific classification of eels:
- Kingdom: Animalia
- Phylum: Chordata
- Class: Pisces
- Subclass: Teleostei
- Order: Synbranchiformes
- Family: Synbranchidae
- Genus: Monopterus
- Species examples: Monopterus albus (rice field eel), Synbranchus bengalensis (swamp eel), Macrotema caligans (sea eel).
Anatomy and Morphology
Despite belonging to the fish family, eells look very different from most fish. They lack pectoral, dorsal, and pelvic fins. Instead, their fins evolved into skin folds, giving them a smooth, snake-like appearance.
- Their bodies are slender, cylindrical, and scaleless.
- The skin feells extremely slippery, almost plastic-like.
- Young eels are yellowish-brown, while adults turn darker brown with a shiny surface.
- They can grow up to 90 cm long, with larger eells usually having thicker bodies.
- Their mouths are wide, with small conical teeth suited for catching prey.
Types of Eels
1. Swamp Eel (Synbranchus bengalensis)
Found in muddy swamps and mangroves, swamp eels are extremely slender with a 1:30 body ratio. They also have tiny soft rays along their body, helping them move through mud and water.
2. Rice Field Eel (Monopterus albus)
Common in Southeast Asian rice fields, this eel has a shorter, thicker body ratio of 1:20. It can survive drought by hiding deep in mud until rain returns, making it a valuable protein source for farmers.
3. Sea Eel (Macrotema caligans)
Living in sandy or rocky seabeds, sea eells grow much larger than their freshwater relatives. With four gill arches and small eyes positioned on their lips, they are uniquely adapted for deep-water environments near coral reefs.
4. Horse Eel (Amphipnous cuchia)
Native to India, the horse eel is fascinating because it has a lung-like sac under its neck. This allows it to breathe outside water for long periods. During dry seasons, it digs into mud and hibernates until the rains return.
Final Answer: Eels Are Fish, Not Snakes
While eells may look like snakes, science proves they belong to the fish family. Their anatomy, gill-based respiration, and classification under Pisces confirm this. So next time you see an eel, you’ll know it’s a slippery fish, not a reptile.