As part of ongoing efforts to explore the mayfly fauna of the Tunga River, Western Ghats, Symbiocloeon madhyasthai Subramanian & Sivaramakrishnan, 2009, has been redescribed based on fresh material collected from the freshwater mussel Pseudomulleria dalyi (Unionoida: Etheriidae) from Western Ghats, India. The association of the bivalve with the mayfly larva reveals several specific morphological traits compared to free-living species. Additionally, larvae lodged in the gill lamellae were observed. The redescriptions update and modify the diagnostic and morphological characters of the larvae based on newly collected specimens.