First record, description and distribution of the colonial ascidian Didemnum psammatodes (Sluiter, 1895) in the Eastern Persian Gulf

Abstract

Non-native ascidians are becoming a global problem and several species have recently been used as models for studying invasion success in the marine realm. Despite a limited dispersal due to their short-lived larvae, they are often found in coastal habitats as a result of human activities. As one of the warmest waterways in the world characterized by heavy marine traffic, the Persian Gulf is particularly prone to invasive ascidians. This study is the first to have documented the occurrence of the colonial ascidian Didemnum psammatodes in natural and man-made substrates in intertidal zones at 15 study sites in Qeshm and Hengam Islands in the Eastern Persian Gulf. High densities of D. psammatodes were observed at several study sites located far from major ports, but close to human residences, which may be explained by the prevalence of hard-surface man-made substrates.