Diversity and distribution of the intertidal Mollusca of the State of Kuwait, Arabian Gulf

Abstract

A total of 271 species of Mollusca from 5 classes, 26 orders, and 87 families were identified in the intertidal macrofauna survey along Kuwaiti coastal areas. A total of 36 sites along Kuwait’s mainland and island areas were sampled quantitatively and qualitatively during late autumn and winter season from December 2013 to December 2015. Of the 271 species, 211 were collected alive; the Gastropoda (104 species) ranked first, followed by the Bivalvia with 100; three species were recorded for the Polyplacophora, and two each for the Scaphopoda, and Cephalopoda. As many as 61 species, notably the micro-molluscs, are probably new records for Kuwait and many of may also be new to science.The most frequently occurring species included Brachidontes pharaonis, Ergalatax junionae, Planaxis savignyi, Leiosolenus tripartitus and Pinctada radiata. Mollusca diversity was higher in rocky-sandy areas than intertidal mudflats. The highest species richness was found in the area of south Kuwait Bay and coastal area around Failaka Island.Comparisons with previous surveys dating back to 1984 indicated that the dominant species composition was relatively unchanged. There are indications of the adverse affects of industrial impacts on the intertidal fauna, including eutrophication and increased turbidity. However, differences in methodology made any quantitative assessment impossible.Wider comparisons with the molluscan faunas of the Arabian Gulf and Arabian region suggest that the fauna of Kuwait has some unique elements not found elsewhere. Taxonomic problems surrounding some of the dominant elements such as the number of species of oysters (Ostreiidae) and mud snails (Cerithiidae) were recognised. The lack of taxonomic congruence between studies and the incomplete taxonomy of the molluscs in general made such comparisons inconclusive but did highlight the need for a revised identification guide to the Mollusca of the Arabian Gulf and Arabian Sea.