Ascidians (Phylum: Chordata, Class: Ascidiacea), or sea squirts, are the largest and most diverse class of the sub-phylum Tunicata (also known asUrochordata). They comprise approximately 3,000 species found in all marine habitats from shallow water to the deep sea. Despite the enormous progress that has been achieved in the field of ascidian research worldwide, only a few studies have focused on the ascidians of the Red Sea and the Eastern Mediterranean.

The current collection, at the Tel Aviv Zoological Museum, is the first to provide an up-to-date museum database of ascidians of these regions with a focus on documenting the arrival and spread of non-indigenous species along the Mediterranean coast. In order to allow identification of ascidians to species level, the live material must be fixed in formaldehyde, preventing in many cases DNA based research from most of the ascidian collections worldwide. The uniqueness of the current collection is that it will enable future molecular based studies on material preserved in Ethanol together with classic taxonomic studies on the matching species. The collection currently includes more than 500 from the Red Sea and Mediterranean and is expanding. The cytochrome c oxidase subunit I from these samples is being sequenced in a collaborative effort with the Smithsonian Barcoding of Life project . So far, seven non-indigenous species have been identified along the Mediterranean coast of Israel including the species Ecteinascidia thurstoni, a putative source for anticancer drug. In addition, three new species to science have been discovered at the Red Sea coast of Israel.