Archive · 18 Aug 2026
Researchers Uncover New Subterranean Earthworm Eel in Gangetic Basin
Scientists found a brand-new kind of tiny fish that lives underground.
The fish is called Gangaichthys indonepalicus.
It was discovered in Bihar, a state in India, near the border with Nepal.
The fish lives deep in the water underground, inside borewells.
People first noticed it after a video on an app called TikTok showed a strange fish coming out of a well.
Scientists then pumped thousands of litres of water out of the wells to find the fish.
The little fish is only about four centimetres long and is colourless because it lives in the dark.
It has tiny eyes covered by skin and does not seem to have ribs.
This is the very first fish of its kind ever found in the Gangetic Basin, which is the land around the Ganga (Ganges) River.
The discovery helps us learn about the hidden animals that live in water deep beneath the ground.
Scientists discovered Gangaichthys indonepalicus, a new subterranean earthworm eel species, in Bihar's Indo-Gangetic Plain.
It is the first stygobitic, or exclusively subterranean, fish recorded from the Gangetic Basin.
The investigation was prompted by a TikTok video posted in 2024 showing an unusual fish emerging from a borewell near the India-Nepal border.
Researchers manually pumped thousands of litres of water from borewells, finding the holotype after about 2,500 litres had been extracted.
Micro-CT scanning and genetic analysis confirmed it as a distinct new genus within the Chaudhuriidae family, with reduced eyes, a translucent unpigmented body and no apparent ribs.
- Who
- An international research team including the Thackeray Wildlife Foundation in Mumbai, the Zoological Survey of India and the Chinese Academy of Sciences, with study authors Akshay Khandekar and Ishan Agarwal.
- What
- The discovery of Gangaichthys indonepalicus, a new species and genus of subterranean earthworm eel and the first stygobitic fish recorded from the Gangetic Basin.
- When
- The investigation began after a TikTok video was posted in 2024; the study was published in the journal ZooKeys, though the article gives no specific publication date.
- Where
- Bihar's Indo-Gangetic Plain, near the India-Nepal border, in borewells of the Gangetic Basin.
- Why
- To identify the unusual fish seen in the TikTok video and document the first subterranean fish from the region's alluvial aquifers.
- New species
- Gangaichthys indonepalicus (gen. et sp. nov.)
- Significance
- First stygobitic fish recorded from the Gangetic Basin and Indo-Gangetic Plain
- Location
- Borewells in Bihar, Indo-Gangetic Plain, near the India-Nepal border
- Family
- Chaudhuriidae (earthworm eels)
- Size
- Roughly 4 centimetres
- Adaptations
- Reduced skin-covered eyes, unpigmented translucent body, apparent absence of ribs
- Sample collection
- First specimen after ~2,000 litres pumped; intact holotype after an additional 500 litres
- Discovery trigger
- 2024 TikTok video of a fish emerging from a borewell