Molecular diversity of coral reef-associated zoanthids off Qeshm Island, northern Persian Gulf

Abstract

The Persian Gulf, a semi-enclosed sea in the subtropical northwest of the Indian Ocean, is noted for its unique biodiversity under its extreme ecological conditions. Despite high biodiversity levels, many groups of marine invertebrates in this area have remained uninvestigated. The order Zoantharia (zoanthids) is one of these taxonomically neglected groups. In this study, diversity of shallow water zoanthids off the Qeshm Island, the largest island in the Persian Gulf, was investigated for the first time. Using in situ field examination integrated with 16S rDNA sequencing and phylogenetic analysis, the presence of three zoanthid species in the inter-tidal and shallow water zone of Qeshm Island were demonstrated: <em>Zoanthus sansibaricus</em> (<em>n</em> = 12) with five morphotypes, <em>Palythoa</em> cf. <em>mutuki</em> (<em>n</em> = 10) with two morphotypes and <em>Palythoa tuberculosa</em> (<em>n</em> = 4) with just one morphotype. In addition to species identification, molecular examination determined phylogenetic relationships of specimens with other previously reported zoanthid species. While <em>Zoanthus sansibaricus</em> and <em>Palythoa tuberculosa</em> are two known zoanthid species, based on molecular data, <em>Palythoa</em> cf. <em>mutuki</em> is potentially a novel undescribed species. However, due to lack of data on zoanthid research and distribution for the entire Persian Gulf, further investigation is needed to clearly ascertain this matter.