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Cannings R.A.,Royal British Columbia Museum | Kahanpaa J.,University of Helsinki
Entomologica Fennica | Year: 2013

Lasiopogon septentrionalis Lehr, 1984 is recorded for the first time from Finland, and Europe as a whole. The species was previously known only from the Russian Far East. A key to the three north European Lasiopogon species is provided. © Entomologica Fennica. 24 June 2013. Source

Wang Q.,Sichuan University | Liu J.,Sichuan University | Allen G.A.,University of Victoria | Ma Y.,Lanzhou University | And 3 more authors.
New Phytologist | Year: 2016

Many plant species comprising the present-day Arctic flora are thought to have originated in the high mountains of North America and Eurasia, migrated northwards as global temperatures fell during the late Tertiary period, and thereafter attained a circumarctic distribution. However, supporting evidence for this hypothesis that provides a temporal framework for the origin, spread and initial attainment of a circumarctic distribution by an arctic plant is currently lacking. Here we examined the origin and initial formation of a circumarctic distribution of the arctic mountain sorrel (Oxyria digyna) by conducting a phylogeographic analysis of plastid and nuclear gene DNA variation. We provide evidence for an origin of this species in the Qinghai-Tibet Plateau of southwestern China, followed by migration into Russia c. 11 million yr ago (Ma), eastwards into North America by c. 4 Ma, and westwards into Western Europe by c. 1.96 Ma. Thereafter, the species attained a circumarctic distribution by colonizing Greenland from both sides of the Atlantic Ocean. Following the arrival of the species in North America and Europe, population sizes appear to have increased and then stabilized there over the last 1 million yr. However, in Greenland a marked reduction followed by an expansion in population size is indicated to have occurred during the Pleistocene. © 2015 New Phytologist Trust. Source

Allen G.A.,University of Victoria | Marr K.L.,Royal British Columbia Museum | McCormick L.J.,University of Victoria | Hebda R.J.,University of Victoria
Ecology and Evolution | Year: 2012

The ranges of arctic-alpine species have shifted extensively with Pleistocene climate changes and glaciations. Using sequence data from the trnH-psbA and trnTtrnL chloroplast DNA spacer regions, we investigated the phylogeography of the widespread, ancient (>3 million years) arctic-alpine plant Oxyria digyna (Polygonaceae). We identified 45 haplotypes and six highly divergent major lineages; estimated ages of these lineages (time to most recent common ancestor, TMRCA) ranged from ̃0.5 to 2.5 million years. One lineage is widespread in the arctic, a second is restricted to the southern Rocky Mountains of the western United States, and a third was found only in the Himalayan and Altai regions of Asia. Three other lineages are widespread in western North America, where they overlap extensively. The high genetic diversity and the presence of divergent major cpDNA lineages within Oxyria digyna reflect its age and suggest that it was widespread duringmuch of its history. The distributions of individual lineages indicate repeated spread of Oxyria digyna through North America over multiple glacial cycles. During the Last Glacial Maximum it persisted in multiple refugia in western North America, including Beringia, south of the continental ice, and within the northern limits of the Cordilleran ice sheet. Our data contribute to a growing body of evidence that arctic-alpine species have migrated from different source regions over multiple glacial cycles and that cryptic refugia contributed to persistence through the Last Glacial Maximum. © 2012 The Authors. Ecology and Evolution published by Blackwell Publishing Ltd. Source

New anatomical details are described for the acanthodian Lupopsyrus pygmaeus Bernacsek & Dineley, 1977, based on newly prepared, nearly complete body fossils from the MOTH locality, Northwest Territories, Canada. New interpretations of previously known structures are provided, while the head, tail, and sensory lines of L. pygmaeus are described for the first time. The pectoral girdle of L. pygmaeus shows no evidence of pinnal and lorical plates as mentioned in the original species description. Instead, the dermal elements of the pectoral region appear to comprise a single pair of prepectoral spines which rest on transversely oriented procoracoids, and large, shallowly inserted, ornamented pectoral fin spines which contact both the procoracoids and scapulocoracoids. The scales of L. pygmaeus lack growth zones and mineralized basal tissue, and superficially resemble scales of thelodonts or monodontode placoid scales of early chondrichthyans, and not the typical scales of acanthodians. However, L. pygmaeus possesses perichondrally-ossified pork-chop shaped scapulocoracoids, a series of hyoidean gill plates, and scale growth that originates near the caudal peduncle; these features suggest a relationship to acanthodians. Prior to this study, both authors conducted separate cladistic analyses which resulted in differing tree positions for L. pygmaeus and its relationships within the Acanthodii. However, both analyses did agree that there is no evidence allying L. pygmaeus to the traditional "climatiid" acanthodians contrary to previous historical classifications. © Publications Scientifiques du Muséum national d'Histoire naturelle, Paris. Source

Efferia okanagana sp. nov. is described from specimens collected in the grasslands of the southern Interior of British Columbia, Canada, mainly the Okanagan Valley. The male and female genitalia are described and illustrated. The existing key to species of Efferia Coquillett is modified to enable identification of male and female E. okanagana. The species belongs to the E. arida species group and perhaps is most closely related to E. arida (Williston) and E. pinali Wilcox. Efferia coulei Wilcox is the closest sympatric relative. Sequences of the cytochrome oxidase I gene (DNA barcode) for E. okanagana and E. coulei show distinct clusters for each species that are approximately 7.0% divergent (uncorrected p distance). Efferia okanagana has an early flight period (May and June) and lives in low-elevation grasslands dominated by bluebunch wheatgrass (Pseudoroegneria spicata (Pursh) . Lve) (Poaceae), especially where the soil is gravelly. It is considered a potential species at risk by the Committee on the Status of Endangered Wildlife in Canada. © 2011 Entomological Society of Canada. Source

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