THÀNH PHẦN VÀ MỐI QUAN HỆ PHÁT SINH LOÀI CUA (MALACOSTRACA: BRACHYURA) Ở DẢI CÂY NGẬP MẶN ĐẦM CÙ MÔNG, PHÚ YÊN

COMPOSITION AND PHYLOGENETIC RELATIONSHIPS OF CRAB (MALACOSTRACA: BRACHYURA) IN THE MANGROVE STRIP OF CU MONG BAY, PHU YEN Crabs, also known as true crabs (Malacostraca: Brachyura), play a key role in the structure and function of the ecosystem as well as have a great influence on other creatures in the mangrove forest. Vietnam is located in an area with a large area of mangrove forests with the highest crab species richness in the world. Previous studies in Vietnam evaluated the diversity of mangrove crab species, but the approach was mainly based on morphological characteristics. The present article presents the species composition and molecular phylogenetic relationships of mangrove crabs in Cu Mong Bay, Phu Yen province. Through two surveys, 9 species belonging to 7 genera, 6 families, 2 superfamilies of crabs were recorded, of which 2 species (Parasesarma peninsulare and Metopograpsus oceanicus) were recorded for the first time in Vietnam. Species composition does not differ between rainy and dry seasons. The phylogenetic tree based on the COI mtDNA gene sequences shows that mangrove crabs are monophyletic at the genus and family level, while polyphyletic at superfamily level with two families Dotillidae and Ocypodidae of the superfamily Ocypodoidea are located on the same branch with families in the superfamily Grapsoidea. The research results contribute to the basis for inventorying crab diversity in coastal marine ecosystems, contributing to proposals for conservation and development of crab resources in Phu Yen.