title: Phylogeographic patterning among two codistributed shrimp species (Crustacea: Decapoda: Palaemonidae) reveals high levels of connectivity across biogeographic regions along the South African coast.
abstract: We compare the genetic structuring and demographic history of two sympatric caridean shrimp species with distinct life history traits, one amphidromous species Palaemon capensis and one marine/estuarine species Palaemon peringueyi, in the historical biogeographical context of South Africa. A total of 103 specimens of P. capensis collected from 12 localities and 217 specimens of P. peringueyi collected from 24 localities were sequenced for the mitochondrial cytochrome oxidase one (CO1) locus. Results from analyses of molecular variance (AMOVA), pairwise ΦST comparisons and haplotype networks demonstrate weak to moderate genetic differentiation in P. capensis and P. peringueyi respectively. P. peringueyi exhibits partial isolation between populations associated with distinct biogeographic regions, likely driven by the region's oceanography. However, there is minimal evidence for the occurrence of discrete regional evolutionary lineages. This demonstrated lack of genetic differentiation is consistent with a marine, highly dispersive planktonic phase in both the amphidromous P. capensis and the marine/estuarine P. peringueyi. Bayesian skyline plots, mismatch expansions and time since expansion indicate that both species maintained stable populations during the Last Glacial Maximum (LGM), unlike other southern African aquatic species.
authors.affiliation: Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, Matieland, South Africa.
authors.forename: Louisa E
authors.initials: LE
authors.lastname: Wood
authors.affiliation: Oxford University Museum of Natural History, Parks Road, Oxford, United Kingdom.
authors.forename: Sammy
authors.initials: S
authors.lastname: De Grave
authors.affiliation: Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, Matieland, South Africa.
authors.forename: Savel R
authors.initials: SR
authors.lastname: Daniels
mesh_terms: D000818:Animals; D060829:Arthropod Proteins / Q000235:genetics; D001499:Bayes Theorem; D005075:Biological Evolution; D004247:DNA / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000235:genetics; D056426:Genetic Loci; D005828:Genetics, Population; D008928:Mitochondria / Q000201:enzymology; D033541:Palaemonidae / Q000145:classification* / Q000235:genetics; D010802:Phylogeny; D058974:Phylogeography; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013019:South Africa
chemical_list: D060829:Arthropod Proteins; D004247:DNA; D003576:Electron Transport Complex IV