• Citer

Population genetic structure of Octopus mimus in the East Pacific

par Buncherd, Natcha
Président du jury Dahdouh-Guebas, Farid
Promoteur Kochzius, Marc
Publication Non publié, 2023-08-31

Mémoire

• Accès en ligne
• Détails
• Contenu
• Statistiques

Résumé :

The East Pacific coast can be divided into biogeographic provinces, which potentially impactthe population genetics of marine species residing in the area. Octopus mimus Gould, 1852 isa shallow-water species with significant fishery value. Therefore, identification andunderstanding of the genetic structure of this species is essential for effective fisherymanagement.A total of 240 Octopus COI gene sequences from Mexico (10), Nicaragua (96), and Peru (134)across three biogeographic provinces (Cortez, Panamanian, and Peru-Chilean) were analyzed.GenBank identification confirmed all sequences as O. mimus with a high similarity value(99.70-100%). The Maximum likelihood phylogenetic tree grouped O. mimus and O.hubbsorum Berry, 1953 (bootstrap value = 96). The Equatorial front population showed thehighest haplotype and nucleotide diversity (h = 0.77, π = 0.48). Population expansion wasobserved in Panamanian and Peru-Chilean provinces. The haplotype network revealed twodistinct haplogroups differing by four mutational steps. Significant population geneticstructure (Фct = 6.67, p < 0.001) with 67.46% of the differences between groups was detected.The first group included populations from Cortez and Panamanian provinces, while thesecond group encompassed populations from the Peru-Chilean province. A similar result wasobtained when populations within the equatorial front range were grouped separately.The result suggests that Octopus mimus and O. hubbsorum on the East Pacific coast are thesame species, with a population structure of two groups: Cortez and Panamanian provincespopulation, and Peru-Chilean population. Alternatively, O. mimus in the Equatorial frontmight be a distinct population. Fishery management should treat the first two populations asseparate units while connectivity should be maintained for the Equatorial front populationwith neighboring provinces.