Varying colour pattern, yet genetically similar: Pebble Crab Seulocia vittata (Stimpson, 1858) (Brachyura: Leucosiidae) from the southeastern coast of India

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Sanjeevi Prakash
Amit Kumar


Five adult specimens of leucosiid crab Seulocia vittata (Stimpson, 1858) were recently collected off the coast of Palk Bay, southern India.  Typical morphological examination revealed the presence of two colour patterns: grey and red.  Interestingly, molecular analysis based on the barcoding gene cytochrome oxidase sub unit I (COI) revealed that both grey and red colour patterns in S. vittata showed 0% sequence divergence between the specimens.  This indicates a situation of reverse cryptic behavior in this crab.  Surprisingly, the evolutionary and ecological processes leading to the absence of genetic divergence and variation in morphology (colour pattern) in S. vittata complex remain to be addressed. 


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Author Biographies

Sanjeevi Prakash, Centre for Climate Change Studies, Sathyabama Institute of Science and Technology, Jeppiaar Nagar, Rajiv Gandhi Salai, Chennai, Tamil Nadu 600119, India.

Currently working as a Scientist at the Centre for Climate Change Studies, Sathyabama Institute of Science and Technology, Chennai

Amit Kumar, Centre for Climate Change Studies, Sathyabama Institute of Science and Technology, Jeppiaar Nagar, Rajiv Gandhi Salai, Chennai, Tamil Nadu 600119, India.

Centre for Climate Change Studies


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