Pantnagar Journal of Research

Abstract

We present an updated checklist of planktonic copepods from Ramsar sites of Kerala viz., Vembanad and Ashtamudi estuary, situated along the Southwest coast of India. Data available in the published records were compiled and updated with data generated from our recent study conducted from 2018 to 2019 from both the estuaries. The combined list includes 105 species of copepods under 42 Genera in 22 Families and 3 Orders; namely Calanoida, Cyclopoida, and Harpacticoida. Common families recorded were Pontellidae (15 species), Acartiidae (13 species), Corycaeidae (12 species), Oithonidae (12 species), Pseudodiaptomidae (9 species), Centropagiidae (8 species) and Paracalanidae (7 species). 67% of species recorded were marine inhabitants and 20% recorded both in marine and estuarine habitats whereas only 10% of species recorded in marine, estuarine and freshwater habitats. True estuarine (Acartia tropica) and true freshwater inhabitants (Heliodiaptomus cinctus and Allodiaptomus mirabilipes) were also recorded during the study. Fifty-three recorded species were common to both the estuaries. In comparison, the Vembanad estuary sustained a higher number of species (100 nos.) than the Ashtamudi estuary (58 nos.). Calanopia metu, a Mediterranean calanoid copepod is also included in the list as it is the first time reported from the Indian waters. Historical studies report the presence of 91 species of copepods under 39 genera of 20 families and 3 orders from both the estuaries. It is also observed that six new species of copepods such as Acartia (Acartiella) keralensis, Pseudodiaptomus malayalus, Acartia bilobata, Archidiaptomus aroorus, Isias cochinensis and Acartia bowmani were added to the science from the Vembanad estuary. Vembanad estuary reports more species of copepods than the Ashtamudi estuary because, Vembanad estuary is more exploited than the Ashtamudi estuary in terms of copepod studies.