Genetic evidence for a single stock of the deep‐sea teleost Beryx decadactylus in the North Atlantic Ocean as inferred from mtDNA control region analysis

Abstract

Mitochondrial control region sequences of 141 alfonsino Beryx decadactylus sampled off the coast of South Carolina were compared with 164 sequences from B. decadactylus collected in the Azores for inferring population structure and demographic history of this deep-water teleost in the North Atlantic Ocean. Analysis of molecular variance showed that 100% of the genetic variation was found within populations, indicating an absence of population structure (Φ(ST) = -0· 003). Neutrality tests and mismatch distribution analyses of pooled sequences suggested that B. decadactylus in the North Atlantic Ocean have undergone population expansion. These results may indicate that transatlantic gene flow occurs, possibly through passive drift of larvae or adult migration. The potential of a shared stock between the eastern and western North Atlantic Ocean will need to be considered if a directed fishery for B. decadactylus were to develop in the U.S.A.

Low levels of global genetic differentiation and population expansion in the deep-sea teleost Hoplostethus atlanticus revealed by mitochondrial DNA sequences

“…This pattern of high haplotype diversity is common in marine fishes and consistent with previous reports for cyt b sequences in orange roughy by Baker et al (1995) and in the bluemouth Helicolenus dactylopterus by Aboim et al (2005). Similarly, high values of diversity have been reported for mtDNA d-loop sequences in other deep-sea fishes such as the thornyhead rockfishes Sebastolobus alascanus, S. altivelis, and S. macrochir, the cape hake Merluccius capensis, the Alaskan Pacific halibut Hippoglossus stenolepis, and the alfonsino Beryx decadactylus (Stepien et al 2000;von der Heyden et al 2007;Nielsen et al 2010;Friess and Sedberry 2011). The lack of genetic differentiation among orange roughy populations from the South Atlantic Ocean and South Pacific Ocean is surprising given the large geographic distances between the regions surveyed in this study.…”

“…There were also changes in oceanic circulation, for example, Rasmussen et al (2003) found that during a period 160,000-10,000 years ago, the Labrador Sea-one of the main areas for deep water formation in the North Atlantic Ocean today-underwent rapid variations in deep-and surface-water circulation coinciding with ice rafting events. It has been inferred that glaciations-interglaciations events and associated changes in the marine environment may have had great effects in the demographic history of many marine fishes as the coastal species Glyptocephalus stelleri and Pennahia argentata (Xiao et al 2010;Han et al 2008) and the deep-sea species as Beryx decadactylus (Friess and Sedberry 2011).…”

“…The larvae of the armorhead remain pelagic for 1.5-2.5 years and have a neustonic distribution with high potential for dispersion by wind-driven currents (Boehlert (Sedberry et al 1996), which is probably related to the long period that juvenile stages spend in the pelagic environment. Several other deep-sea species show genetic homogeneity among populations and have pelagic larval and juvenile stages that last for several months and could be passively transported by ocean currents (Hoarau and Borsa 2000;von der Heyden et al 2007;Friess and Sedberry 2011).…”

Global and New Caledonian patterns of population genetic variation in the deep-sea splendid alfonsino, Beryx splendens, inferred from mtDNA

“…Previous genetic studies on other fish species associated with seamounts and oceanic islands have demonstrated a lack of genetic structure on regional and even on oceanic scales, e.g., wreckfish Polyprion americanus, armourhead Pseudopentaceros wheeleri (Martin et al 1992;Sedberry et al 1996) and B. decadactylus, a species closely related to that of our study, from the North Atlantic (Friess and Sedberry 2011a). Inversely, other studies on deep-sea fish reported evidence of genetic structure in oceanic populations, e.g., the roundnose grenadier, Coryphaenoides rupestris (White et al 2010), Pacific cod Gadus macrocephalus (Liu et al 2010) and, on a finer scale, the blackbelly rosefish Helicolenus dactylopterus (Aboim et al 2005).…”

Genetic Variations in Two Seahorse Species (Hippocampus mohnikei and Hippocampus trimaculatus): Evidence for Middle Pleistocene Population Expansion

“…Alphabetical letters indicate the seahorse groups: (A) outgroup for H. trimaculatus ; (B) H. mohnikei group (under the influence of the Yellow Sea circulations (dotted arrows) [48]); and (C) H. trimaculatus group (under the influence of overall seasonal circulation in the South China Sea [black arrows in winter and grey arrows in summer] [44], [45]). …”