Molecular Identification of the Persian Gulf Sea Hare (Aplysia sp.) Based on 16s rRNA Gene Sequence

Sea hares of the Aplysia genus are among the mollusks of interest for various researchers to study their phylogeny, bioactive compounds and the nervous system. These mollusks are herbivorous and produce chemical compounds (ink) to defend themselves. The present study provided molecular identification of the Persian Gulf (Bushehr city) sea hare using 16s rRNA gene sequence.

Sampling was done in coastal waters of Bushehr (Bushehr Province, Iran). Total DNA was extracted using CTAB method and target DNA was amplified by 16sar-L and 16sbr-H universal primers. For phylogenetic analysis, both Maximum Likelihood and Bayesian methods (by RAxML and Mr. Bayes programs, respectively) were used. For ML algorithm, 1000 bootstrap replicates were generated. In Bayesian approach, the program was implemented for 20 million generations and one tree for every 1000 generations was sampled.

Based on the obtained tree from ML method, Persian Gulf sea hare and Aplysia dactylomela were placed in a clade with 87% bootstrap and high posterior probability (PP=1). The obtained phylogenetic tree from Bayesian approach showed similar topology. The Persian Gulf sea hare with 95.8% bootstrap and PP=1 was again supported in the sister group of A. dactylomela.

The results from the molecular analysis of 16s rRNA gene sequence indicate probable existence of a new species of sea hare in the Persian Gulf region. In order to determine the exact position of the present species, the phylogenetic analysis of COI gene sequence and morphological characteristics are essentials.