Lakshmanan, R.; Saravanan, R.; Kalidas, C.; Rajendran, P.; Babu, A.M.; Asha, P.S., and Joshi, K.K., 2024. Occurrence of the non-native mauve stinger, Pelagia cf. noctiluca, in coastal waters off Cape Comorin, southern Bay of Bengal. Journal of Coastal Research, 40(6), 1103–1110. Charlotte (North Carolina), ISSN 0749-0208.

During a jellyfish survey in the southern Bay of Bengal, India, four scyphozoan jellyfish from the family Pelagiidae (Order: Semaeostomeae) were observed. The observed specimens were found at a depth of 1 to 2 m off the coast of Arockiapuram (8°05′ N, 77°11′ E), Cape Comorin (now Kanyakumari). The underwater photographic and video documentation with live colouration enabled the identification of the collected specimens as mauve stingers, Pelagia noctiluca (Forskal, 1775). The observed specimens have pink- or mauve-coloured hemispherical umbrellas with eight marginal tentacles that are transversely wrinkled and eight pear-shaped rhopalia. In general, P. noctiluca has a common distribution along the Atlantic Ocean, the Mediterranean Sea, and the Pacific Ocean; however, recordings of this species in Indian waters are considered rare and out of its documented distribution area. It has been reported earlier from Indian waters, and the nearest known distribution is from the Gulf of Mannar, Bay of Bengal. This species shows an invasive distribution in the warmer tropical environments due to its wide range of temperature tolerance. The species can be considered “invasive” as the periodic occurrence of large abundances in coastal waters occurs when this typically offshore species is advected shoreward in years when population densities appear to be exceptionally high. Consequently, it is problematic at the very periphery of its “natural range,” thus differing from truly invasive species that have been introduced into a new area. The findings in this study suggest that specific hydrodynamic conditions may transport the permanent offshore population of P. noctiluca inshore, resulting in non-native outbreaks on shores. The study sheds light on the presence of the non-native oceanic mauve stinger in the Cape Comorin coastal waters in the Bay of Bengal, which alters the fisheries and tourism industries because it has a negative interaction with human recreational and coastal fishing activities.