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bioRxiv · 10.1101/128033

Burrow Morphology of Genus Ocypode (Brachyura: Decapoda: Ocypodidae) Along the Coast of Karachi

Odhano, S.·Saher, N. U.
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Abstract

Burrow morphology of Ocypode rotundata and O. ceratophthalma was studied on the sandy beach of Karachi with the aim of identifying their significance and relationship to the shore environment. The small sized burrows found at low tide level and large sized burrows found at the high tide level up to dry or splash zone. The burrow count during the winter season was lower as compared summer season. Only single burrow opening was observed in O. rotundata and O. ceratophthalma oriented towards the sea. The burrow depth was between 460 to 1300 mm and 490 to 760 mm in O. rotundata and O. ceratophthalma respectively. Strong correlation (r2=81.2 and 89.2%) was observed between carapace length and burrow diameter of the O. rotundata and O. ceratophthalma respectively. For the grain size analysis, maximum amount of grain resulted with fine sand 57.04% (2.5{Phi}, 3.0{Phi}). For anthropogenic analysis, data showed no any significant difference (P value =0.128 and 0.671) from two sites but number of burrow counts decreases as the number of human activity increasing day by day at the selected beaches.

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Odhano, S., Saher, N. U.. 2017-04-17. Burrow Morphology of Genus Ocypode (Brachyura: Decapoda: Ocypodidae) Along the Coast of Karachi. https://doi.org/10.1101/128033

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