Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Plants (Basel) ; 13(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38202323

RESUMO

The exploration of liverworts on Bering Island (the westernmost Aleutians) has revealed plants assigned to the recently described and previously monotypic Konstantinovia, previously known only from Yunnan Province of China, and belonging to the bigeneric Obtusifoliaceae. The collected plants are described here as Konstantinovia beringii sp. nov. The known localities of two species of Konstantinovia are separated by more than 6000 km, while the presence of the genus on the Commander Islands is probably a relict. Phylogenetic examination of both collected specimens and new material from other related families resulted in the construction of a fairly well-supported phylogenetic tree for the entire Cephaloziellaceae s.l. + Scapaniaceae s.l. clade. The constructed trees have confirmed the previously stated assumption that it is necessary to segregate one more family within this superclade, described here as Oleolophoziaceae fam. nov.

2.
PeerJ ; 10: e13260, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35497188

RESUMO

We present an integrative molecular and morphological study of subaquatic representatives of the genus Pseudohygrohypnum (Pylaisiaceae, Bryophyta), supplemented by distribution modelling of the revealed phylogenetic lineages. Phylogenetic analyses of nuclear and plastid datasets combined with the assemble species by automatic partitioning (ASAP) algorithm revealed eight distinct species within the traditionally circumscribed P. eugyrium and P. subeugyrium. These species are therefore yet another example of seemingly widely distributed taxa that harbour molecularly well-differentiated lineages with narrower distribution ranges. Studied accessions that were previously assigned to P. eugyrium form three clearly allopatric lineages, associated with temperate regions of Europe, eastern North America and eastern Asia. Remarkably, accessions falling under the current morphological concept of P. subeugyrium were shown to be even more diverse, containing five phylogenetic lineages. Three of these lineages occur under harsh Asian continental climates from cool-temperate to Arctic regions, while the remaining two, referred to P. subeugyrium s.str. and P. purpurascens, have more oceanic North Atlantic and East Asian distributions. Niche identity and similarity tests suggested no similarity in the distributions of the phylogenetically related lineages but revealed the identity of two East Asian species and the similarity of two pairs of unrelated species. A morphological survey confirmed the distinctness of all eight phylogenetic lineages, requiring the description of five new species. Pseudohygrohypnum appalachianum and P. orientale are described for North American and East Asian plants of P. eugyrium s.l., while P. sibiricum, P. subarcticum and P. neglectum are described for the three continental, predominantly Asian lineages of P. subeugyrium s.l. Our results highlight the importance of nontropical Asia as a center of bryophyte diversity. Phylogenic dating suggests that the diversification of subaquatic Pseudohygrohypnum lineages appeared in late Miocene, while mesophilous species of the genus split before Miocene cooling, in climatic conditions close to those where the ancestor of Pseudohygrohypnum appeared. We speculate that radiation of the P. subeugyrium complex in temperate Asia might have been driven by progressive cooling, aridification, and increases in seasonality, temperature and humidity gradients. Our results parallel those of several integrative taxonomic studies of North Asian mosses, which have resulted in a number of newly revealed species. These include various endemics from continental areas of Asia suggesting that the so-called Rapoport's rule of low diversity and wide distribution range in subpolar regions might not be applicable to bryophytes. Rather, the strong climatic oscillations in these regions may have served as a driving force of speciation and niche divergence.


Assuntos
Briófitas , Bryopsida , Filogenia , Filogeografia , Ásia Oriental , Ásia
3.
New Phytol ; 231(2): 763-776, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33507570

RESUMO

The arbuscular mycorrhizal (AM) fungi are a globally distributed group of soil organisms that play critical roles in ecosystem function. However, the ecological niches of individual AM fungal taxa are poorly understood. We collected > 300 soil samples from natural ecosystems worldwide and modelled the realised niches of AM fungal virtual taxa (VT; approximately species-level phylogroups). We found that environmental and spatial variables jointly explained VT distribution worldwide, with temperature and pH being the most important abiotic drivers, and spatial effects generally occurring at local to regional scales. While dispersal limitation could explain some variation in VT distribution, VT relative abundance was almost exclusively driven by environmental variables. Several environmental and spatial effects on VT distribution and relative abundance were correlated with phylogeny, indicating that closely related VT exhibit similar niche optima and widths. Major clades within the Glomeraceae exhibited distinct niche optima, Acaulosporaceae generally had niche optima in low pH and low temperature conditions, and Gigasporaceae generally had niche optima in high precipitation conditions. Identification of the realised niche space occupied by individual and phylogenetic groups of soil microbial taxa provides a basis for building detailed hypotheses about how soil communities respond to gradients and manipulation in ecosystems worldwide.


Assuntos
Micorrizas , Ecossistema , Fungos , Concentração de Íons de Hidrogênio , Filogenia , Solo , Microbiologia do Solo , Temperatura
4.
Plants (Basel) ; 9(7)2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640627

RESUMO

The taxonomic diversity center of Schistochilopsis is in East Asia, where the genus also shows the highest genetic diversity and morphological plasticity. The integrative survey of Schistochilopsis in East Asia was the main goal of the present account. Plant materials were obtained from recent collections made by authors in various parts of amphi-Pacific Asia; several types of specimens were also studied. The study includes phylogenetic reconstructions from nuclear ITS1,2, chloroplast trnL and trnG sequences, and anatomo-morphological, biogeographical, and taxonomical analyses. As a result, it was concluded that S. obscura should be transferred to Lophozia s. str. and S. grandiretis to the newly described genus Protochilopsis. Lophozia boliviensis was found to be part of the Andean-Sino-Himalayan taxon belonging to Schistochilopsis. The species status of S. hyperarctica and S. opacifolia was not confirmed. Substantial genetic variation is observed within S. incisa with possible cryptic sympatric distributed entities. The taxonomical section of the paper provides a discussion on the status, distinctive morphological traits, distribution, and ecology supplemented with the morphological description for poorly understood taxa. In the vast majority of cases, the illustrations and photographs made from the types and living material are provided.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...