COI Gene-Based-Molecular Identification of Invasive Craspedacusta sowerbii Lankester, 1880 (Hydrozoa, Limnomedusa) Freshwater Jellyfish in Arga-Parvati Wetlands, Gonda District, Uttar Pradesh
Shravan K. Sharma *
Mumbai Research Centre, ICAR-Central Institute of Fisheries Technology, Vashi, India.
Manoharmayum Shaya Devi
ICAR- Central Inland Fisheries Research Institute, Barrackpore, Kolkata, India.
B. K. Behera
ICAR- Central Inland Fisheries Research Institute, Barrackpore, Kolkata, India.
Absar Alam
ICAR- Central Inland Fisheries Research Institute, Prayagraj Regional Centre, India.
Suman Kumari
ICAR- Central Inland Fisheries Research Institute, Barrackpore, Kolkata, India.
R. K. Manna
ICAR- Central Inland Fisheries Research Institute, Barrackpore, Kolkata, India.
Asim Jana
ICAR- Central Inland Fisheries Research Institute, Barrackpore, Kolkata, India.
Shalaka R. Salunkhe
Mumbai Research Centre, ICAR-Central Institute of Fisheries Technology, Vashi, India.
B. K. Das
ICAR- Central Inland Fisheries Research Institute, Barrackpore, Kolkata, India.
*Author to whom correspondence should be addressed.
Abstract
This study reports the first molecularly confirmed occurrence of the freshwater jellyfish Craspedacusta sowerbii (Lankester, 1880) from northern India, recorded in the Arga-Parvati wetland complex of Gonda District, Uttar Pradesh. Species identification was achieved through an integrative approach combining morphological and molecular analyses. Morphologically, the medusa displayed a flattened hemispherical bell (mean diameter 15 ± 1.8 mm), four simple radial canals with corresponding pouch like gonads and 200 marginal tentacles bearing birhopaloid nematocysts. Molecular characterization using the mitochondrial Cytochrome C Oxidase subunit I (COI) gene (709 bp) confirmed 100% similarity with the Chinese isolate (KF510026.1) and 95% with the German isolate (FJ423619.1), indicating low genetic divergence and suggesting a globally conserved lineage. Phylogenetic analysis clustered the Indian isolate with C. sowerbii populations from China, Germany and Morocco with strong bootstrap support (86–100%), affirming its invasive potential. Physico-chemical analysis revealed warm (avg. 29.42 ± 1.90 °C), slightly alkaline (pH 7.7-7.9) and phosphate-enriched (0.34 ± 0.03 mg L⁻¹) conditions characteristic of eutrophic systems. The proliferation and decay of Eichhornia crassipes (Water hyacinth) likely enhanced phosphate release and organic load, stimulating algal and zooplankton productivity that favored jellyfish blooms. The findings demonstrate a trophic link between eutrophication and jellyfish proliferation and emphasize C. sowerbii as an indicator of nutrient enrichment while underscoring the need for wetland nutrient and macrophyte management.
Keywords: Invasive hydrozoan, peach blossom jellyfish, medusa, wetland eutrophication