The first record of three imperative jellyfish species from the coastal waters of Sri Lanka

Abstract

Jellyfishes (Phylum Cnidaria) are important as a delicacy, ornamental animal, collagen source and bio-indicator of climatic changes. In spite of this, jellyfishes have negative impacts on fisheries and tourist industries too, where they clog fishing nets and sting recreational water users respectively. Only a few jellyfish species have been recorded from the Sri Lankan coastal waters. In the present study, jellyfish species reported in the coastal waters of Sri Lanka during January 2017 to April 2018 are presented here. From a systematic survey, jellyfishes were collected and preserved in 5% formalin for taxonomic identification. Altogether forty species were identified based on their morphological features using standard identification guides. Of these species, Chrysaora chinensis Vanhöffen, 1888, Crambionella orsini Vanhöffen, 1888 and Chironex indrasaksajiae Sucharitakul, 2017, were recorded for the first-time from the Sri Lankan waters. Chrysaora chinensis (n= 432) was found along the entire coastal belt of the country, C. orsini (n=5) was found from northern, northwestern and southeastern coasts while C. indrasaksajiae (n=4) was found only from eastern coast during the study period. Among the three species, C. orsini was the largest, having a bell diameter of ~200 mm, followed by C. chinensis and C. indrasaksajiae having bell diameters of ~140 mm and ~110 mm respectively. Of the three species, C. chinensis and C. indrasaksajiae are highly hazardous to human health while C. orsini is a harmless, edible jellyfish which is heavily fished for export market from the southeast coastal waters of Sri Lanka.