Deep genetic divergence between austral populations of the red alga Gigartina skottsbergii reveals a cryptic species endemic to the Antarctic continent

Abstract

Deep genetic divergence between austral populations of the red alga Gigartina skottsbergii reveals a cryptic species endemic to the Antarctic continent. Polar Biology, Springer Verlag, 2015, 38 (12), pp.2021-2034 periods and the existence of dispersal barrier due to the ACC. On both sides of the ACC, the 33 last Quaternary glaciations have induced strong bottlenecks that were followed by rapid 34 colonization events. 35Click here to download Manuscript: POBI-D-14-00293_revised-ms.docx Click here to view linked

Unexpected absence of island endemics: Long‐distance dispersal in higher latitude sub‐Antarctic Siphonaria (Gastropoda: Euthyneura) species

“…Our results show that two species of pulmonate limpet, Siphonaria lateralis and S. fuegiensis , occur across vast distances of the Southern Ocean, from the Pacific and Atlantic coasts of Patagonia eastward to the Falkland/Malvinas (FI), South Georgia (SG), Kerguelen (KI) and Macquarie Islands (MI). The presence of two such widespread direct‐developing species is a surprise considering that several studies have revealed locally endemic cryptic species on different island groups in the Southern Ocean across different marine invertebrate groups (Gonzalez‐Wevar et al., ; Janosik et al., ; Leese et al., ; Wilson et al., ), macroalgae (Billard, Reyes, Mansilla, Faugeron, & Guillemin, ; Fraser et al., ) and fishes (Dornburg, Federman, Eytan, & Near, ). In these latter cases, there appears to be a limited connectivity among benthic marine populations, regardless of dispersal capacity (Moon et al., ).…”

“…Macquarie Islands (MI). The presence of two such widespread directdeveloping species is a surprise considering that several studies have revealed locally endemic cryptic species on different island groups in the Southern Ocean across different marine invertebrate groups (Gonzalez-Wevar et al, 2017;Janosik et al, 2011;Leese et al, 2008;Wilson et al, 2009), macroalgae (Billard, Reyes, Mansilla, Faugeron, & Guillemin, 2015;Fraser et al, 2013) and fishes (Dornburg, Federman, Eytan, & Near, 2016). In these latter cases, there appears to be a limited connectivity among benthic marine populations, regardless of dispersal capacity (Moon et al, 2017).…”

Comparative phylogeography of six red algae along the Antarctic Peninsula: extreme genetic depletion linked to historical bottlenecks and recent expansion

“…In the Southern Ocean, most studies using molecular approaches to determine the existence of divergent lineages and cryptic species have focused on fishes and marine invertebrates (Allcock and Strugnell 2012). Surprisingly, until now, genetic structure of macroalgae has been largely neglected (but see Fraser et al 2012;Fraser et al 2013;Billard et al 2015;Fraser 2016) despite the fact that they represent an important part of benthic communities both as resources (i.e., primary producers) and as community structural components (Amsler et al 2014). The diversity pump has been proposed to be particularly relevant in Antarctic organisms with a limited capacity for dispersal since populations located in refugia could easily be thoroughly isolated, leading to allopatric divergence (Clarke et al 1992;Wilson et al 2009;Allcock and Strugnell 2012;Verheye et al 2016).…”

Oxidative balance in macroalgae from Antarctic waters. Possible role of Fe

“…rocks and boulders), and occur in distinct vertical zonation mainly between the intertidal and the subtidal zone down to 30 m depth (Wiencke and Clayton, 2002). The red alga Gigartina skottsbergii, Setchell and Gardner 1936, is a subtidal species that occurs in the Antarctic Peninsula, the South Shetland Islands and the South Orkney Islands (Billard et al, 2015). It is morphologically similar to the algae named G. skottsbergii from South America, but probably represents a separate species (Billard et al, 2015;Hommersand et al, 2009).…”

“…The red alga Gigartina skottsbergii, Setchell and Gardner 1936, is a subtidal species that occurs in the Antarctic Peninsula, the South Shetland Islands and the South Orkney Islands (Billard et al, 2015). It is morphologically similar to the algae named G. skottsbergii from South America, but probably represents a separate species (Billard et al, 2015;Hommersand et al, 2009). It is a pseudoperennial macroalga whose blades may reach up to 60 cm or more (Wiencke and Clayton, 2002).…”