A team of researchers from the Estuarine Biology Regional Centre of the Zoological Survey of India recently discovered a new fish species named Pseudorhombus bahudaensis in the Bahuda estuary in Odisha.
About Pseudorhombus bahudaensis
Pseudorhombus bahudaensis is a new species of flounder fish discovered in October 2025 in the Bahuda estuary in Odisha, India. The discovery was made by researchers from the Zoological Survey of India (ZSI). 
Key facts about Pseudorhombus bahudaensis:

• Identification: For decades, this flatfish was misidentified as the more widespread Gangetic largetooth flounder (Pseudorhombus arsius). Using a combination of DNA barcoding and morphological analysis, scientists determined that it is, in fact, a distinct species.
• Genetic lineage: Genetic testing revealed that P. bahudaensis diverged from its relative P. arsius approximately 17 million years ago, a discovery that was previously masked by their physical similarities.
• Habitat: As a demersal, or bottom-dwelling fish, it inhabits the silty and muddy bottoms of estuaries and coastal bays. It can tolerate brackish water and is known to move between saltwater and freshwater environments.
• Physical characteristics: Like other flounders, P. bahudaensis has a flattened body and both eyes are located on the left side of its head. It can be distinguished from P. arsius by a broader body, a different pattern of lateral line scales, and variations in its dorsal fin rays.

Significance:
The discovery highlights the rich biodiversity of the Bahuda estuary and the wider western Bay of Bengal.
It has direct implications for fisheries management, as flounders are commercially valuable. Accurate species identification is crucial for creating sustainable exploitation and conservation strategies. 

Download Pdf