Complete female mitochondrial genome of Mytilus chilensis

Abstract

The controversy surrounding the origin of antitropical distribution of Mytilus mussels and the taxonomic status of southern hemisphere populations remain unsolved, despite the efforts. One of the limiting factors remains the lack of the complete sequences of the representative mitochondrial genomes which would allow their proper comparison with the relatively well-represented northern hemisphere congeneric mussels. To fill this gap we sequenced the representative maternal (F) genome of a native Chilean mussel. The genome is 16,748bp long and structurally identical to the northern hemisphere M. edulis and M. galloprovincialis F genomes. However, the genetic distance from them (≈5%) is twice as high as the maximum distance between them (<2.5%). Thus, the notion that the name M. chilensis should be used for native Chilean Mytilus mussels, with the same rank as M. galloprovincialis and M. edulis is supported.

Native and invasive taxa on the Pacific coast of South America: Impacts on aquaculture, traceability and biodiversity of blue mussels (Mytilus spp.)

“…In addition, the SNPs results support the hypothesis that the native Chilean blue mussel has a unique evolutionary history in the Southern Hemisphere. Similarly, Śmietanka and Burzyński (), who analysed the complete sequence of the female mitogenome of the native Chilean blue mussel, reported that the genetic distance between M. edulis and M. galloprovincialis (~2.5%) was half the distance that separates M. chilensis from either of these two species (5%), a result that indicates that the native Chilean mussel is a separate taxon within the genus Mytilus .…”

“…(), in their review of allozyme and morphometric variation of Chilean blue mussels, confirmed that the Southern Hemisphere form of M. edulis occurs “ along the shores from the North Patagonia region of Chile to the southern tip of the South American continent” (p. 52, Borsa et al., ) and concluded that native Chilean blue mussels should be assigned subspecific rank and named M. edulis platensis d'Orbigny 1846. Numerous authors, using a range of different molecular markers, have reported molecular genetic differences between the native Chilean blue mussel and reference Northern Hemisphere M. edulis and/or M. galloprovincialis (e.g., Astorga et al., ; Gérard et al., ; Śmietanka & Burzyński, ; Westfall & Gardner, ). Regardless of the taxonomic recommendation made by these (and several other) research groups, the common theme is that native Mytilus from South America, and often specifically from Chile, are genetically different from other smooth‐shelled blue mussels anywhere in the world.…”

“…Interestingly, this situation is often not reflected in current taxonomic websites such as WoRMS and ITIS. Subsequently, but much later on, proteinbased (allozyme) and morphometric assessments of blue mussels led McDonald et al (1991) to conclude that mussels from South America Numerous authors, using a range of different molecular markers, have reported molecular genetic differences between the native Chilean blue mussel and reference Northern Hemisphere M. edulis and/ or M. galloprovincialis (e.g., Astorga et al, 2015;Gérard et al, 2008;Śmietanka & Burzyński, 2017;Westfall & Gardner, 2010). Regardless of the taxonomic recommendation made by these (and several other) research groups, the common theme is that native Mytilus from South America, and often specifically from Chile, are genetically different from other smooth-shelled blue mussels anywhere in the world.…”

Blue mussels of the Mytilus edulis species complex from South America: The application of species delimitation models to DNA sequence variation

“…However, there has been longstanding debate about the existence of other smooth-shelled blue mussel species, dating back over 100 years (refer to [ 15 – 17 ] for reviews and to Hilbish et al [ 14 ]; Gérard et al [ 18 ] for more recent molecular interpretations). This is true for all of the Southern hemisphere, but particularly so for the Atlantic and Pacific coasts of South America, despite a large body of work addressing the subject in regions such as Chile (e.g., [ 18 – 28 ] and references therein). To the best of our knowledge, models of species delimitation have not been applied to the Mytilus edulis species complex problem, although they may have the ability to resolve the global taxonomy of this widespread and important group.…”

“…edulis platensis [ 24 ], as M . platensis [ 26 , 34 ], as a Southern hemisphere lineage of Mytilus galloprovincialis also found in other Pacific Ocean regions such as New Zealand and Australia [ 22 , 23 , 35 ], as Mytilus edulis chilensis [ 36 , 37 ], and as Mytilus chilensis [ 28 , 38 – 43 ]. Several authors have noted that different marker types and analyses of different genomes (i.e., mitochondrial versus nuclear DNA) may provide different answers, and that newer generations of marker types, increased genomic coverage, and also wider geographic sampling may be required to definitively answer the question of which species occur where (e.g., McDonald et al [ 13 ], Oyarzún et al [ 41 ], Larraín et al [ 43 ]).…”