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Manta and devil rays are an iconic group of globally distributed pelagic filter feeders, yet their evolutionary history remains enigmatic. We employed next generation sequencing of mitogenomes for nine of the 11 recognized species and two outgroups; as well as additional Sanger sequencing of two mitochondrial and two nuclear genes in an extended taxon sampling set. Analysis of the mitogenome coding regions in a Maximum Likelihood and Bayesian framework provided a well-resolved phylogeny. The deepest divergences distinguished three clades with high support, one containing Manta birostris, Manta alfredi, Mobula tarapacana, Mobula japanica and Mobula mobular; one containing Mobula kuhlii, Mobula eregoodootenkee and Mobula thurstoni; and one containing Mobula munkiana, Mobula hypostoma and Mobula rochebrunei. Mobula remains paraphyletic with the inclusion of Manta, a result that is in agreement with previous studies based on molecular and morphological data. A fossil-calibrated Bayesian random local clock analysis suggests that mobulids diverged from Rhinoptera around 30 Mya. Subsequent divergences are characterized by long internodes followed by short bursts of speciation extending from an initial episode of divergence in the Early and Middle Miocene (19-17 Mya) to a second episode during the Pliocene and Pleistocene (3.6 Mya - recent). Estimates of divergence dates overlap significantly with periods of global warming, during which upwelling intensity - and related high primary productivity in upwelling regions - decreased markedly. These periods are hypothesized to have led to fragmentation and isolation of feeding regions leading to possible regional extinctions, as well as the promotion of allopatric speciation. The closely shared evolutionary history of mobulids in combination with ongoing threats from fisheries and climate change effects on upwelling and food supply, reinforces the case for greater protection of this charismatic family of pelagic filter feeders., (Copyright © 2014 Elsevier Inc. All rights reserved.)

We examined 733 individuals of Fucusspiralis from 21 locations and 1093 Fucusvesiculosus individuals from 37 locations throughout their northern hemisphere ranges using nuclear and mitochondrial markers. Three genetic entities of F. spiralis were recovered. In northern and sympatric populations, the presence of "F. spiralis Low" in the mid-intertidal and "F. spiralis High" in the high-intertidal was confirmed and both co-occurred with the sister species F. vesiculosus. The third and newly-discovered entity, "F. spiralis South", was present mainly in the southern range, where it did not co-occur with F. vesiculosus. The South entity diverged early in allopatry, then hybridized with F. vesiculosus in sympatry to produce F. spiralis Low. Ongoing parallel evolution of F. spiralis Low and F. spiralis High is most likely due to habitat preference/local selection and maintained by preferentially selfing reproductive strategies. Contemporary populations of F. spiralis throughout the North Atlantic stem from a glacial refugium around Brittany involving F. spiralis High; F. spiralis South was probably unaffected by glacial episodes. Exponential population expansion for F. vesiculosus began during the Cromer and/Holstein interglacial period (300,000-200,000 yrs BP). Following the last glacial maximum (30,000-22,000 yrs BP), a single mtDNA haplotype from a glacial refugium in SW Ireland colonized Scandinavia, the Central Atlantic islands, and the W Atlantic., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Species of Fucus are among the dominant seaweeds along Northern Hemisphere shores, but taxonomic designations often are confounded by significant intraspecific morphological variability. We analyzed intra- and inter-specific phylogenetic relationships within the genus (275 individuals representing 16 taxa) using two regions of the mitochondrion: a variable intergenic spacer and a conserved portion of the 23S subunit. Bayesian ML and MP analyses verified a shallow phylogeny with two major lineages (previously reported) and resolved some intra-lineage relationships. Significant species-level paraphyly/polyphyly was observed within lineages 1A and 2. Despite higher species richness in the North Atlantic, a North Pacific origin of the genus is supported by a gradient of decreasing haplotype and nucleotide diversities in F. distichus from the North Pacific to the East Atlantic.