Scylla species found in Cochin backwaters, Kerala, South India

Abstract

The present study described the Scylla species collected from Cochin backwaters for two years from June 2010 to May 2012. Identification and description of Scylla species were carried out based on the morphological characters focusing on the first and second male gonopods, and third maxillipeds. The first male pleopods of the three species were found to be similar in shape, but variations were observed in the setation pattern. S. serrata and S. tranquebarica showed two patches of setae on the inner margin on its posterior end, which was thin and inconspicuous in the former, while thick and conspicuous in the latter. S. olivacea was found to possess only a single tuft of thick setae on the inner margin of the first male pleopod. The second male pleopods were similar in S. serrata and S. tranquebarica, while found to be varied in S. olivacea. The second male pleopods were found to possess setation on the inner margin on its posterior region in S. olivacea, which was totally absent in S. serrata and S. tranquebarica. There were no significant variations in the third maxillipeds among the three Scylla spp. The third maxillipeds of three Scylla spp. were characterized by broad and flattened merus and ischium, lined with thick hairs on the inner margin. The present study shows the occurrence of three species, Scylla serrata, S. tranquebarica and S. olivacea, in Cochin backwaters. However identification of species needs to be confirmed using molecular techniques.