Lesser Spiny Eel (Macrognathus aculeatus) Care Guide
Macrognathus aculeatus is an Asian spiny eel reaching about 38 cm, with a narrow snout used to probe sand for invertebrates.
Compiled by Aquairi from published sources · Published · Updated
Overview
Macrognathus aculeatus, the lesser or one-stripe spiny eel, is an elongated freshwater fish of the family Mastacembelidae from Asia. It has a narrow tubular snout that it uses to probe sand for food, and a single dark dorsal stripe.
Taxonomy
- Family: Mastacembelidae
- Genus: Macrognathus
- Scientific name: Macrognathus aculeatus
- Common synonym: One-stripe Spiny Eel
Habitat
FishBase records the species across Asia, including Thailand, the Malay Peninsula, Borneo, Indonesia, Bangladesh, Nepal, India and Vietnam. It occurs in medium to large rivers and lowland wetlands and is benthopelagic; it lives in freshwater and has been recorded in brackish water.
Tank requirements
- Minimum tank volume: 200 L
- Temperature: 24-28 °C (75-82 °F)
- pH: 6.5-7.5
- GH: 5-15 °dGH
- Lifespan: 8-12 years
- Substrate: sand (for burrowing)
Diet
The lesser spiny eel is a carnivore that probes the substrate for worms and other invertebrates. In the aquarium it is fed roughly every two days on meaty and live foods.
Compatibility
This is a peaceful, crepuscular bottom-dweller. Suitable tankmates include larger barbs and loaches, while tiny nano fish and shrimp may be eaten and should be avoided. A sand substrate allows natural burrowing.
Conservation status
IUCN Red List: Least Concern (assessed 2019).
Breeding the Lesser Spiny Eel (Macrognathus aculeatus)
Overview
The Lesser Spiny Eel (Macrognathus aculeatus) is an Asian mastacembelid reaching about 38 cm TL, found in freshwater and brackish habitats across Thailand, the Malay Peninsula, Borneo, Indonesia and into Bangladesh, Nepal, India and Vietnam. It is a potamodromous, crepuscular and nocturnal burrower of medium to large rivers, lowland wetlands and peat areas, and is listed Least Concern by the IUCN (FishBase; Wikipedia).
Conditioning
FishBase reports high fecundity, with a minimum of 1,000 eggs, indicating a productive seasonal spawner. Conditioning relies on heavy feeding of live and frozen meaty foods over a sand substrate the eel can probe and burrow into, prior to a simulated wet-season change.
Breeding Setup
Unusually for a bottom-dweller, the roots of floating plants are favoured as the spawning site, so a setup should combine an open sand bed with dense floating cover. The species' potamodromous behaviour points to a rising-water, rainy-season cue (FishBase).
Spawning Behavior & Trigger
Spawning is linked to the wet season; FishBase gives the high egg count but limited behavioural detail, so the principal documented elements are the seasonal trigger and the floating-root spawning site. Soft, slightly acidic water with a temperature in the 23-28 C range matches the natural conditions (FishBase).
Egg & Fry Care
Eggs are deposited among floating-plant roots. With over a thousand eggs possible, ample plant cover is needed; specific incubation and fry-feeding timings for this species are not detailed in the available sources, so they are omitted here rather than estimated.
Common Challenges
Reliable sexing is difficult, the seasonal trigger must be recreated, and the burrowing adults may disturb or consume eggs. Because home spawnings are exceptional, this remains an advanced project.