Morphological discrimination of female specimens of Pseudodiaptomus annandalei from Cochin estuary and Corbyn's Cove Creek, India

Pseudodiaptomus annandalei is a brackish water calanoid copepod first reported and described by Sewell in 1919 from Chilka lake. Preliminary information on morphological differences observed in the examination of female specimens of P. annandalei collected from two geographically separated locations namely, Cochin estuary in Kerala and Corbyn's Cove Creek, in Andaman & Nicobar (A&N) Islands are presented in this paper. The specimens collected from both localities showed variations in length of antennules, total body length, spinulation on Pdg segments, ornamentation on posterior corner of metasome, proportional lengths of Pr and Ur, length width ratio of P5, urosome spinulation, and size and shape of caudal setae. These intra-specific differences are described to expand the known morphological range of this species and to provide the first comparative analysis of P. annandalei from two locations, Cochin estuary and A&N islands in India.