Westernmost record of the Japanese spiny dragonet, Callionymus draconis (Actinopterygii, Callionymiformes, Callionymidae), from Tamil Nadu, southern India

The Japanese spiny dragonet, Callionymus draconis Nakabo, 1977, a member of the subgenus Callionymus (Spinicapitichthys), was previously known only from the eastern Indian Ocean and the western Pacific, with records from southern Japan and Western Australia. This study reports the first record of C. draconis from India, based on a single male specimen (71.0 mm SL) collected from trawl bycatch off Kanyakumari, Tamil Nadu, southeastern Arabian Sea (southernmost port in India).

This finding represents a significant westward range extension of approximately 5200 km, establishing the westernmost known limit of the species distribution. Furthermore, the collection depth of 80 to 100 m constitutes the shallowest recorded occurrence for this species, indicating a broader bathymetric range than previously known. This record bridges a major biogeographical gap in the known distribution of C. draconis, enriches the documented marine fish diversity of India, and highlights the importance of bycatch surveys in revealing cryptic marine biodiversity and refining the understanding of Indo-Pacific fish biogeography.