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1.
PhytoKeys ; 217: 1-135, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36760228

RESUMO

The Arctic ecozone is undergoing a rapid transformation in response to climate change. Establishing a baseline of current Arctic biodiversity is necessary to be able to track changes in species diversity and distribution over time. Here, we report a vascular plant floristic study of Katannilik Territorial Park, Kimmirut and vicinity within Circumpolar Arctic Bioclimate Subzone D on southern Baffin Island, Nunavut, Canada. We compiled a dataset of 1596 collections gathered in the study area throughout the last century, including 838 we made in 2012. The vascular flora comprises 35 families, 98 genera, 211 species, two nothospecies and seven infraspecific taxa. We newly recorded 51 taxa in 22 families in the study area: Erigeroneriocephalus, Taraxacumholmenianum (Asteraceae), Drabaarctica, D.fladnizensis, D.lactea (Brassicaceae), Campanularotundifolia (Campanulaceae), Arenarialongipedunculata, Honckenyapeploidessubsp.diffusa, Sabulinarossii, Sileneuralensissubsp.uralensis, Viscariaalpina (Caryophyllaceae), Carexbrunnescenssubsp.brunnescens, C.krausei, C.microglochin, C.subspathacea, C.williamsii, Eriophorumscheuchzerisubsp.arcticum (Cyperaceae), Andromedapolifolia, Orthiliasecundasubsp.obtusata (Ericaceae), Oxytropispodocarpa (Fabaceae), Luzulagroenlandica (Juncaceae), Triglochinpalustris (Juncaginaceae), Utriculariaochroleuca (Lentibulariaceae), Huperziacontinentalis (Lycopodiaceae), Montiafontana (Montiaceae), Corallorhizatrifida, Platantheraobtusatasubsp.obtusata (Orchidaceae), Hippurislanceolata, H.vulgaris, Plantagomaritima (Plantaginaceae), Calamagrostisneglectasubsp.groenlandica, C.purpurascens, Festucaproliferavar.lasiolepis, F.rubrasubsp.rubra, F.rubrasubsp.arctica, Hordeumjubatumsubsp.jubatum, Leymusmollissubsp.mollis, L.mollissubsp.villosissimus, Puccinelliavaginata (Poaceae), Primulaegaliksensis (Primulaceae), Cryptogrammastelleri (Pteridaceae), Coptidium×spitsbergense (Ranunculaceae), Potentillacrantzii, P.hyparcticasubsp.hyparctica, Rubuschamaemorus, Sibbaldiaprocumbens (Rosaceae), Salixfuscescens (Salicaceae), Micranthesfoliolosa, M.nivalis, M.tenuis (Saxifragaceae) and Woodsiaalpina (Woodsiaceae). We recorded 196 taxa in Katannilik Territorial Park (191 species, three infraspecific taxa and two nothospecies); 145 of these taxa are first records for the park. We recorded 170 taxa in Kimmirut and vicinity (166 species, three infraspecific taxa and one nothospecies) in Kimmirut and vicinity; 15 of these taxa are first records for Kimmirut and vicinity. All study area species are native, except two grasses that grew in Kimmirut: F.rubrasubsp.rubra, which may have been seeded and Hordeumjubatumsubsp.jubatum, of unknown origin. We summarize the distribution on Baffin Island for each taxon recorded in the study area, including several unpublished southern Baffin Island records.

2.
PeerJ ; 10: e13884, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36193423

RESUMO

To investigate phylogenetic relationships among and within major lineages of Bromus, with focus on Bromus sect. Bromus, we analyzed DNA sequences from two nuclear ribosomal (ITS, ETS) and two plastid (rpl32-trnLUAG , matK) regions. We sampled 103 ingroup accessions representing 26 taxa of B. section Bromus and 15 species of other Bromus sections. Our analyses confirm the monophyly of Bromus s.l. and identify incongruence between nuclear ribosomal and plastid data partitions for relationships within and among major Bromus lineages. Results support classification of B. pumilio and B. gracillimus within B. sect. Boissiera and B. sect. Nevskiella, respectively. These species are sister groups and are closely related to B. densus (B. sect. Mexibromus) in nrDNA trees and Bromus sect. Ceratochloa in plastid trees. Bromus sect. Bromopsis is paraphyletic. In nrDNA trees, species of Bromus sects. Bromopsis, Ceratochloa, Neobromus, and Genea plus B. rechingeri of B. sect. Bromus form a clade, in which B. tomentellus is sister to a B. sect. Genea-B. rechingeri clade. In the plastid trees, by contrast, B. sect. Bromopsis species except B. tomentosus form a clade, and B. tomentosus is sister to a clade comprising B. sect. Bromus and B. sect. Genea species. Affinities of B. gedrosianus, B. pulchellus, and B. rechingeri (members of the B. pectinatus complex), as well as B. oxyodon and B. sewerzowii, are discordant between nrDNA and plastid trees. We infer these species may have obtained their plastomes via chloroplast capture from species of B. sect. Bromus and B. sect. Genea. Within B. sect. Bromus, B. alopecuros subsp. caroli-henrici, a clade comprising B. hordeaceus and B. interruptus, and B. scoparius are successive sister groups to the rest of the section in the nrDNA phylogeny. Most relationships among the remaining species of B. sect. Bromus are unresolved in the nrDNA and plastid trees. Given these results, we infer that most B. sect. Bromus species likely diversified relatively recently. None of the subdivisional taxa proposed for Bromus sect. Bromus over the last century correspond to natural groups identified in our phylogenetic analyses except for a group including B. hordeaceus and B. interruptus.


Assuntos
Bromus , Poaceae , Filogenia , Bromus/genética , DNA de Plantas/genética , Triticum/genética , Plastídeos/genética
3.
PhytoKeys ; 141: 1-330, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32201471

RESUMO

Victoria Island in Canada's western Arctic is the eighth largest island in the world and the second largest in Canada. Here, we report the results of a floristic study of vascular plant diversity of Victoria Island. The study is based on a specimen-based dataset comprising 7031 unique collections from the island, including some 2870 new collections gathered between 2008 and 2019 by the authors and nearly 1000 specimens variously gathered by N. Polunin (in 1947), M. Oldenburg (1940s-1950s) and S. Edlund (1980s) that, until recently, were part of the unprocessed backlog of the National Herbarium of Canada and unavailable to researchers. Results are presented in an annotated checklist, including keys and distribution maps for all taxa, citation of specimens, comments on taxonomy, distribution and the history of documentation of taxa across the island, and photographs for a subset of taxa. The vascular plant flora of Victoria Island comprises 38 families, 108 genera, 272 species, and 17 additional taxa. Of the 289 taxa known on the island, 237 are recorded from the Northwest Territories portion of the island and 277 from the Nunavut part. Thirty-nine taxa are known on the island from a single collection, seven from two collections and three from three collections. Twenty-one taxa in eight families are newly recorded for the flora of Victoria Island: Artemisia tilesii, Senecio lugens, Taraxacum scopulorum (Asteraceae); Crucihimalaya bursifolia, Draba fladnizensis, D. juvenilis, D. pilosa, D. simmonsii (Brassicaceae); Carex bigelowii subsp. bigelowii, Eriophorum russeolum subsp. albidum (Cyperaceae); Anthoxanthum monticola subsp. monticola, Bromus pumpellianus, Deschampsia cespitosa subsp. cespitosa, D. sukatschewii, Festuca rubra subsp. rubra, Lolium perenne, Poa pratensis subsp. pratensis (Poaceae); Stuckenia filiformis (Potamogetonaceae); Potentilla × prostrata (Rosaceae); Galium aparine (Rubiaceae); and Salix ovalifolia var. ovalifolia (Salicaceae). Eight of these are new to the flora of the Canadian Arctic Archipelago: Senecio lugens, Draba juvenilis, D. pilosa, Anthoxanthum monticola subsp. monticola, Bromus pumpellianus, Deschampsia cespitosa subsp. cespitosa, Poa pratensis subsp. pratensis and Salix ovalifolia var. ovalifolia. One of these, Galium aparine, is newly recorded for the flora of Nunavut. Four first records for Victoria Island are introduced plants discovered in Cambridge Bay in 2017: three grasses (Festuca rubra subsp. rubra, Lolium perenne, and Poa pratensis subsp. pratensis) and Galium aparine. One taxon, Juncus arcticus subsp. arcticus, is newly recorded from the Northwest Territories. Of the general areas on Victoria Island that have been botanically explored the most, the greatest diversity of vascular plants is recorded in Ulukhaktok (194 taxa) and the next most diverse area is Cambridge Bay (183 taxa). The floristic data presented here represent a new baseline on which continued exploration of the vascular flora of Victoria Island - particularly the numerous areas of the island that remain unexplored or poorly explored botanically - will build.

4.
PhytoKeys ; (87): 1-139, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29114171

RESUMO

Circumscriptions of and relationships among many genera and suprageneric taxa of the diverse grass tribe Poeae remain controversial. In an attempt to clarify these, we conducted phylogenetic analyses of >2400 new DNA sequences from two nuclear ribosomal regions (ITS, including internal transcribed spacers 1 and 2 and the 5.8S gene, and the 3'-end of the external transcribed spacer (ETS)) and five plastid regions (matK, trnL-trnF, atpF-atpH, psbK-psbI, psbA-rps19-trnH), and of more than 1000 new and previously published ITS sequences, focused particularly on Poeae chloroplast group 1 and including broad and increased species sampling compared to previous studies. Deep branches in the combined plastid and combined ITS+ETS trees are generally well resolved, the trees are congruent in most aspects, branch support across the trees is stronger than in trees based on only ITS and fewer plastid regions, and there is evidence of conflict between data partitions in some taxa. In plastid trees, a strongly supported clade corresponds to Poeae chloroplast group 1 and includes Agrostidinae p.p., Anthoxanthinae, Aveninae s.str., Brizinae, Koeleriinae (sometimes included in Aveninae s.l.), Phalaridinae and Torreyochloinae. In the ITS+ETS tree, a supported clade includes these same tribes as well as Sesleriinae and Scolochloinae. Aveninae s.str. and Sesleriinae are sister taxa and form a clade with Koeleriinae in the ITS+ETS tree whereas Aveninae s.str. and Koeleriinae form a clade and Sesleriinae is part of Poeae chloroplast group 2 in the plastid tree. All species of Trisetum are part of Koeleriinae, but the genus is polyphyletic. Koeleriinae is divided into two major subclades: one comprises Avellinia, Gaudinia, Koeleria, Rostraria, Trisetaria and Trisetum subg. Trisetum, and the other Calamagrostis/Deyeuxia p.p. (multiple species from Mexico to South America), Peyritschia, Leptophyllochloa, Sphenopholis, Trisetopsis and Trisetum subg. Deschampsioidea. Graphephorum, Trisetum cernuum, T. irazuense and T. macbridei fall in different clades of Koeleriinae in plastid vs. nuclear ribosomal trees, and are likely of hybrid origin. ITS and matK trees identify a third lineage of Koeleriinae corresponding to Trisetum subsect. Sibirica, and affinities of Lagurus ovatus with respect to Aveninae s.str. and Koeleriinae are incongruent in nuclear ribosomal and plastid trees, supporting recognition of Lagurus in its own subtribe. A large clade comprises taxa of Agrostidinae, Brizinae and Calothecinae, but neither Agrostidinae nor Calothecinae are monophyletic as currently circumscribed and affinities of Brizinae differ in plastid and nuclear ribosomal trees. Within this clade, one newly identified lineage comprises Calamagrostis coarctata, Dichelachne, Echinopogon (Agrostidinae p.p.) and Relchela (Calothecinae p.p.), and another comprises Chascolytrum (Calothecinae p.p.) and Deyeuxia effusa (Agrostidinae p.p.). Within Agrostidinae p.p., the type species of Deyeuxia and Calamagrostis s.str. are closely related, supporting classification of Deyeuxia as a synonym of Calamagrostis s.str. Furthermore, the two species of Ammophila are not sister taxa and are nested among different groups of Calamagrostis s.str., supporting their classification in Calamagrostis. Agrostis, Lachnagrostis and Polypogon form a clade and species of each are variously intermixed in plastid and nuclear ribosomal trees. Additionally, all but one species from South America classified in Deyeuxia sect. Stylagrostis resolve in Holcinae p.p. (Deschampsia). The current phylogenetic results support recognition of the latter species in Deschampsia, and we also demonstrate Scribneria is part of this clade. Moreover, Holcinae is not monophyletic in its current circumscription because Deschampsia does not form a clade with Holcus and Vahlodea, which are sister taxa. The results support recognition of Deschampsia in its own subtribe Aristaveninae. Substantial further changes to the classification of these grasses will be needed to produce generic circumscriptions consistent with phylogenetic evidence. The following 15 new combinations are made: Calamagrostis × calammophila, C. breviligulata, C. breviligulata subsp. champlainensis, C. × don-hensonii, Deschampsia aurea, D. bolanderi, D. chrysantha, D. chrysantha var. phalaroides, D. eminens, D. eminens var. fulva, D. eminens var. inclusa, D. hackelii, D. ovata, and D. ovata var. nivalis. D. podophora; the new name Deschampsia parodiana is proposed; the new subtribe Lagurinae is described; and a second-step lectotype is designated for the name Deyeuxia phalaroides.

5.
PeerJ ; 5: e2835, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28194307

RESUMO

The Coppermine River in western Nunavut is one of Canada's great Arctic rivers, yet its vascular plant flora is poorly known. Here, we report the results of a floristic inventory of the lower Coppermine River valley and vicinity, including Kugluk (Bloody Falls) Territorial Park and the hamlet of Kugluktuk. The study area is approximately 1,200 km2, extending from the forest-tundra south of the treeline to the Arctic coast. Vascular plant floristic data are based on a review of all previous collections from the area and more than 1,200 new collections made in 2014. Results are presented in an annotated checklist, including citation of all specimens examined, comments on taxonomy and distribution, and photographs for a subset of taxa. The vascular plant flora comprises 300 species (311 taxa), a 36.6% increase from the 190 species documented by previous collections made in the area over the last century, and is considerably more diverse than other local floras on mainland Nunavut. We document 207 taxa for Kugluk (Bloody Falls) Territorial Park, an important protected area for plants on mainland Nunavut. A total of 190 taxa are newly recorded for the study area. Of these, 14 taxa (13 species and one additional variety) are newly recorded for Nunavut (Allium schoenoprasum, Carex capitata, Draba lonchocarpa, Eremogone capillaris subsp. capillaris, Sabulina elegans, Eleocharis quinqueflora, Epilobium cf. anagallidifolium, Botrychium neolunaria, Botrychium tunux, Festuca altaica, Polygonum aviculare, Salix ovalifolia var. arctolitoralis, Salix ovalifolia var. ovalifolia and Stuckenia pectinata), seven species are newly recorded for mainland Nunavut (Carex gynocrates, Carex livida, Cryptogramma stelleri, Draba simmonsii, Festuca viviparoidea subsp. viviparoidea, Juncus alpinoarticulatus subsp. americanus and Salix pseudomyrsinites) and 56 range extensions are reported. The psbA-trnH and rbcL DNA sequence data were used to help identify the three Botrychium taxa recorded in the study area. Three new combinations are proposed: Petasites frigidus subsp. sagittatus (Banks ex Pursh) Saarela, Carex petricosa subsp. misandroides (Fernald) Saarela and Carex simpliciuscula subsp. subholarctica (T. V. Egorova) Saarela.

6.
Front Microbiol ; 6: 1084, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26528252

RESUMO

Single cell Chelex® DNA extraction and nested PCR amplification were used to examine partial gene sequences from natural diatom populations for taxonomic and phylogenetic studies at and above the level of species. DNA was extracted from cells that were either fresh collected or stored in RNAlater. Extractions from Lugol's fixation were also attempted with limited success. Three partial gene sequences (rbcL, 18S, and psbA) were recovered using existing and new primers with a nested or double nested PCR approach with amplification and success rates between 70 and 96%. An rbcL consensus tree grouped morphologically similar specimens and was consistent across the two primary sample treatments: fresh and RNAlater. This tool will greatly enhance the number of microscopic diatom taxa (and potentially other microbes) available for barcoding and phylogenetic studies. The near-term increase in sequence data for diatoms generated via routine single cell extractions and PCR will act as a multiproxy validation of longer-term next generation genomics.

7.
PhytoKeys ; (52): 23-79, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26311505

RESUMO

The Canadian Arctic Archipelago is a vast region of approximately 1,420,000 km(2), with a flora characterized by low species diversity, low endemicity, and little influence by alien species. New records of vascular plant species are documented here based on recent fieldwork on Victoria and Baffin Islands; additional records based on recent literature sources are mentioned. This paper serves as an update to the 2007 publication Flora of the Canadian Arctic Archipelago, and brings the total number of vascular plants for the region to 375 species and infraspecific taxa, an increase of 7.7%. Three families (Amaranthaceae, Juncaginaceae, Pteridaceae) and seven genera (Cherleria L., Cryptogramma R. Br., Platanthera Rich., Sabulina Rchb., Suaeda Forssk. ex J.F. Gmel., Triglochin L., Utricularia L.) are added to the flora, and one genus is deleted (Minuartia L.). Five species are first records for Nunavut (Arenarialongipedunculata Hultén, Cryptogrammastelleri (S.G. Gmel.) Prantl, Puccinelliabanksiensis Consaul, Saxifragaeschscholtzii Sternb., Utriculariaochroleuca R.W. Hartm.).

8.
PLoS One ; 8(10): e77982, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24348895

RESUMO

Accurate identification of Arctic plant species is critical for understanding potential climate-induced changes in their diversity and distributions. To facilitate rapid identification we generated DNA barcodes for the core plastid barcode loci (rbcL and matK) for 490 vascular plant species, representing nearly half of the Canadian Arctic flora and 93% of the flora of the Canadian Arctic Archipelago. Sequence recovery was higher for rbcL than matK (93% and 81%), and rbcL was easier to recover than matK from herbarium specimens (92% and 77%). Distance-based and sequence-similarity analyses of combined rbcL + matK data discriminate 97% of genera, 56% of species, and 7% of infraspecific taxa. There is a significant negative correlation between the number of species sampled per genus and the percent species resolution per genus. We characterize barcode variation in detail in the ten largest genera sampled (Carex, Draba, Festuca, Pedicularis, Poa, Potentilla, Puccinellia, Ranunculus, Salix, and Saxifraga) in the context of their phylogenetic relationships and taxonomy. Discrimination with the core barcode loci in these genera ranges from 0% in Salix to 85% in Carex. Haplotype variation in multiple genera does not correspond to species boundaries, including Taraxacum, in which the distribution of plastid haplotypes among Arctic species is consistent with plastid variation documented in non-Arctic species. Introgression of Poa glauca plastid DNA into multiple individuals of P. hartzii is problematic for identification of these species with DNA barcodes. Of three supplementary barcode loci (psbA-trnH, psbK-psbI, atpF-atpH) collected for a subset of Poa and Puccinellia species, only atpF-atpH improved discrimination in Puccinellia, compared with rbcL and matK. Variation in matK in Vaccinium uliginosum and rbcL in Saxifraga oppositifolia corresponds to variation in other loci used to characterize the phylogeographic histories of these Arctic-alpine species.


Assuntos
Código de Barras de DNA Taxonômico , Plantas/genética , Plastídeos/genética , Ribulose-Bifosfato Carboxilase/genética , Regiões Árticas , Biodiversidade , Canadá , Variação Genética , Haplótipos , Plantas/classificação , Ribulose-Bifosfato Carboxilase/química , Alinhamento de Sequência , Análise de Sequência de DNA
9.
Mol Ecol Resour ; 10(1): 69-91, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21564992

RESUMO

Previous research on barcoding sedges (Carex) suggested that basic searches within a global barcoding database would probably not resolve more than 60% of the world's some 2000 species. In this study, we take an alternative approach and explore the performance of plant DNA barcoding in the Carex lineage from an explicitly regional perspective. We characterize the utility of a subset of the proposed protein-coding and noncoding plastid barcoding regions (matK, rpoB, rpoC1, rbcL, atpF-atpH, psbK-psbI) for distinguishing species of Carex and Kobresia in the Canadian Arctic Archipelago, a clearly defined eco-geographical region representing 1% of the Earth's landmass. Our results show that matK resolves the greatest number of species of any single-locus (95%), and when combined in a two-locus barcode, it provides 100% species resolution in all but one combination (matK + atpFH) during unweighted pair-group method with arithmetic mean averages (UPGMA) analyses. Noncoding regions were equally or more variable than matK, but as single markers they resolve substantially fewer taxa than matK alone. When difficulties with sequencing and alignment due to microstructural variation in noncoding regions are also considered, our results support other studies in suggesting that protein-coding regions are more practical as barcoding markers. Plastid DNA barcodes are an effective identification tool for species of Carex and Kobresia in the Canadian Arctic Archipelago, a region where the number of co-existing closely related species is limited. We suggest that if a regional approach to plant DNA barcoding was applied on a global scale, it could provide a solution to the generally poor species resolution seen in previous barcoding studies.

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