Common Worm Eel

Moringua Microchir
Common Worm Eel - Marinewise © 2025 MarineWise

Quick Facts

Scientific name Moringua Microchir
Other names Spaghetti Eel, Lesser Thrush Eel
Size Up to 47 cm (18.5 in)
Weight Under .50 kg (1.1 lb)

Distribution

Habitat & AU Distribution Coastal & brackish waters, estuaries, rivers & reefs in sandy bottom areas
Depth Range 1 - 20 m (65 ft)
Common Worm Eel Distribution

Interesting Info

  • The Common Worm Eel is a slender, snake-like eel that lives in tropical and subtropical waters of northern Australia—from Western Australia, across the Top End, and down to Queensland.
  • It is called a “worm eel” because its body is extremely thin and flexible, resembling a large earthworm in the sand.
  • Their body is cylindrical, brown to grey-brown in colour, paler underneath, and lacks the prominent scales or patterns of many other eels.
  • They have very small eyes and a short, rounded snout—adaptations for their burrowing lifestyle.
  • The dorsal and anal fins are extremely reduced and merge with the tail, giving them a worm-like appearance.
  • They live buried in sandy or muddy bottoms in estuaries, lagoons, and sheltered bays, usually in depths of 1–20 m (3–65 ft).
  • Juveniles and smaller individuals are often found in shallower estuaries, while adults may burrow deeper in coastal sandflats.
  • They feed on tiny benthic invertebrates, such as worms, small crustaceans, and molluscs, which they detect using their sense of smell rather than sight.
  • At night, they emerge from burrows to forage, then retreat into the sand during the day to avoid predators.
  • They spawn in open water, releasing eggs that hatch into transparent, ribbon-like larvae known as leptocephali.
  • These larvae drift in the plankton for weeks or months before transforming into bottom-dwelling juveniles.
  • They are prey for larger predatory fish such as flatheads, trevallies, and groupers, as well as wading birds in shallow habitats.
  • They are rarely seen as they spend most of their lives hidden in sand or mud.
  • Their burrowing helps aerate and mix sediments, playing a small but useful role in estuarine ecosystems.
Species Interaction

Aquarium, Elusive Species

Common Worm Eels can occasionally be found in home aquariums, although they require specialised care due to their unique needs. They need a tank that replicates their natural habitat, with a sandy or muddy substrate and plenty of hiding places like PVC pipes or caves. They are a burrowing, nocturnal species making human interactions with this species minimal.

Scientific Classification

Kingdom: Animalia

Phylum: Chordata

Class: Actinopterygii

Order: Anguilliformes

Family: Moringuidae

Genus: Moringua

Species: Moringua Microchir

Conservation Status

The conservation status of the Common Worm Eel in Australia is not specifically assessed or listed on the International Union for Conservation of Nature (IUCN) Red List. This means that there is no official categorisation of their conservation status at the global level.

Common Worm Eel
As Aquarium Fish

Care Level: Moderate to difficult

Temperament: Aggressive

Diet: Carnivore

Reef Compatible: Yes

Minimum Tank Size: 100 gallons

Elusive / Overlooked Species

Finding: Difficult

Temperament: Shy

Location: Inner reef

Danger: None