First record of the dragonet species, Synchiropus monacanthus (Callionymiformes, Callionymidae), from India: An eastward range extension in the Indian Ocean

The South African bigeye dragonet, Synchiropus monacanthus Smith, 1935 (family Callionymidae), is reported for the first time from Indian waters based on six female specimens (68.2–104.5 mm SL) collected from trawl bycatch off Pudukkottai, southeastern India (Palk Bay). This record extends the known distribution of S. monacanthus eastward by approximately 2500 km from its previously documented range in the western Indian Ocean (South Africa, Mozambique, Madagascar, Tanzania, Socotra Archipelago).

The specimens were collected at a depth of approximately 100–150 m, which is shallower than the previously reported bathymetric range of 175–428 m for this species, providing new information on its habitat depth. Comparative morphological data are provided to distinguish S. monacanthus from its congener, Synchiropus lineolatus (Valenciennes, 1837), which is also recorded from Indian waters. This finding adds a second species of Synchiropus to the Indian marine ichthyofauna and highlights the value of examining deep-water trawl bycatch for documenting species distributions.