Tal Gordon

Ascidians (Phylum: Chordata, Class: Ascidiacea), or sea squirts, will seldom attract the attention of an enthusiastic diver in the tropical coral-reefs. In highly diverse reefs such as those in the Red Sea the ascidians often hide in shaded areas on natural substrates, underneath corals and stones, and it requires a dedicated exploration of the substrate in order to spot them. Ascidians are nonetheless highly diverse and colorful, possessing fascinating traits and endless possibilities for scientific exploration. The ascidian fauna of the Red Sea is characterized with a high percentage of unique species, yet, the arrival of non-indigenous species to urbanized areas has been recently documented. Marine pollution poses additional threats to the indigenous fauna, which is currently not included in any specific conservation planning. Here we provide a general overview of Red Sea ascidians, including current trends in their research, in order to encourage further scientific studies on this overlooked group of unique invertebrates dispersed in various tropical environments.