Misidentification And Notes On Plesionika Semilaevis, Spence Bate, 1888 (Crustacean: Decapoda: Caridea) From The Southern Coast Of India

The commercial deep-sea caridean shrimp Plesionika martia (Milne-Edwards 1883) has long been recorded from India and constitutes an important species of deep-sea shrimp catches in the southern coast of India. However, the present study revealed that all the previous records of "Plesionika martia" is actually a misidentification of the closely related species P. semilaevis, which was recently obtained from Indian waters. The specimens were collected from three fish landing harbours (Sakthikulangara, Kalamuku, and Tuticorin) fished from the depth of about 150-250 m along the southern coast of India during 2014 to 2017. The level of interspecies genetic divergence between 16S rDNA (16.8-18.6%) and COI (26.1%) sequences of the Indian P. semilaevis and P. martia sequence retrieved from NCBI were found to be comparatively high. The current work illustrates the detailed morphological characters with color photographs of the species, P. semilaevis off the Indian Exclusive Economic Zone (EEZ).