Molecular and morphological evidence for the presence of a non-native oyster (genus Crassostrea) in the Persian Gulf

• Published in: Zoologischer Anzeiger 2022-01, Vol.296, p.120-128
• Main Authors: Ghaffari, Hamze, Ahmadzadeh, Faraham, Saberi-Pirooz, Reihaneh, Abtahi, Behrooz
• Format: Article
• Language: English
• Subjects: Biofouling; Ecological impacts; Invasive species; North Persian Gulf; Shell morphology
• ISSN: 0044-5231; 1873-2674
• DOI: 10.1016/j.jcz.2021.12.002

Oysters are widespread throughout the intertidal regions, and accurate identification and monitoring of their ecological status are still difficult due to their high level of plasticity. Anthropogenic activities facilitate oyster dispersal to new habitats through the shipping and elimination of existing barriers. In this study, a combination of morphological and molecular techniques was used to clarify the identity of an oyster species occurring along the Iranian coast of the Persian Gulf. Specimens were collected from the jetties of the ports and the rocky shores along the northern Persian Gulf. Oyster identification was carried out to the lowest possible taxonomic level based on shell morphology. The phylogenetic analysis was done using the cytochrome c oxidase subunit 1 (COI) fragments. Morphological results confirmed that studied samples belong to the genus Crassostrea and showed close to the Vietnamese (Crassostrea markushuberi) species. Molecular analysis reveals that species are a sister species to a clade containing Crassostrea zhanjiangensis and Crassostrea talonata. According to the relatively high genetic distances and lack of similarity in shell characteristics, the species is considered as distant sister species of C. zhanjiangensis and C. talonata. The results showed a non-native small size of oyster in the northern Persian Gulf, which might be a new species. The relative abundance of this species in the introduced location (Imam Khomeini port) may be linked to the high adaptation capability to the new environment.