TikTok Sensation Leads to Discovery of New Subterranean Eel Species in India
BIHAR, INDIA – In a remarkable intersection of citizen science and academic research, scientists have formally identified a new genus and species of subterranean earthworm eel, Gangaichthys indonepalicus, thriving beneath the northern Indian state of Bihar. The discovery, detailed in the journal ZooKeys, was ignited by a 2024 TikTok video showcasing an unusual, tiny fish emerging from a borewell.
Named for its connection to the iconic Ganges River, Gangaichthys indonepalicus translates to "fish of the Ganga," with its specific epithet reflecting its distribution along the India-Nepal border. This marks a significant find, as it is the first subterranean fish species to be recorded from the vast Gangetic Basin.
Tejas Thackeray, a co-author of the study, explained the naming convention: "As the species occurs on the border between India and Nepal, we picked indonepalicus as the specific epithet, which reflects the distribution of the species."
The newly identified eel measures approximately 4cm (1.6 inches) in length and exhibits striking adaptations to its life in perpetual darkness. These include eyes covered by skin, an unpigmented and translucent body, and a conspicuous absence of ribs – all features characteristic of species that inhabit lightless underground environments.
The journey to formally identify Gangaichthys indonepalicus was an arduous one for researchers. Intensive fieldwork in Bihar involved manually pumping thousands of litres of water from local handpumps in an effort to procure a specimen.
Akshay Khandekar, another author of the study, described the challenges: "Procuring samples of this unusual fish was challenging. Identifying potential hand pumps (borewells) and wells, and obtaining permission from their owners to extract water for the purpose of searching for the fish proved difficult." He added that the fieldwork intensified considerably when they "began manually pumping water."
After an estimated 2,000 litres of water were pumped, the first specimen was finally retrieved, though it unfortunately sustained damage and did not survive. Persistence paid off, however, as a second, intact specimen was found from the same borewell after an additional 500 litres of water were pumped.
Subsequent genetic analysis and CT X-ray scans definitively confirmed that the specimen represented an entirely distinct genus within the earthworm eel family Chaudhuriidae.
Ishan Agarwal, another key researcher, emphasized that this discovery underscores India’s rich biodiversity, which encompasses vast gradients in climate, topography, and multiple biogeographic regions. He also highlighted the significant knowledge gap that still exists, with countless species yet to be discovered.
The eel falls into the category of "stygobitic" species – aquatic animals that exclusively inhabit underground water sources. Dr. Agarwal noted the significance of this particular find: "This is the first stygobitic fish from the Indo-Gangetic plains and from the Gangetic basin."
The initial TikTok video proved instrumental, providing the crucial lead that spurred scientific investigation. As the researchers stated, "The unique morphology of the fish in the video, and the fact that there are no known stygobitic fish from the region, motivated us to track down the species to ascertain its identity." This unexpected discovery highlights the growing role of social media in bringing previously unknown natural phenomena to the attention of the scientific community.
