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1.
PhytoKeys ; 237: 219-230, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38317827

RESUMO

A new species, Veronicakurdistanica (Plantaginaceae), is described and illustrated. It grows on limestone cliffs in mountainous alpine areas of western Iran (Kurdistan province). The new species belongs to the species group of V.kurdica and is considered to be closely related to V.daranica, V.khorassanica and V.kurdica, with which the new species is compared. Molecular phylogenetic analysis of nrDNA (ITS) region confirms this relationship. Veronicakurdistanica is distinguished from the mentioned species by its glandular indumentum, length and shape of leaves and bracts, number of flowers per raceme, length and width of calyx and corolla, and size of capsules and seeds.

2.
Biology (Basel) ; 11(5)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35625367

RESUMO

Veronica subgenus Pentasepalae is the largest subgenus of Veronica in the Northern Hemisphere with approximately 80 species mainly from Southwest Asia. In order to reconstruct the phylogenetic relationships among the members of V. subgenus Pentasepalae and to test the "out of the Iranian plateau" hypothesis, we applied thorough taxonomic sampling, employing nuclear DNA (ITS) sequence data complimented with morphological studies and chromosome number counts. Several high or moderately supported clades are reconstructed, but the backbone of the phylogenetic tree is generally unresolved, and many Southwest Asian species are scattered along a large polytomy. It is proposed that rapid diversification of the Irano-Turanian species in allopatric glacial refugia and a relatively high rate of extinction during interglacial periods resulted in such phylogenetic topology. The highly variable Asian V. orientalis-V. multifida complex formed a highly polyphyletic assemblage, emphasizing the idea of cryptic speciation within this group. The phylogenetic results allow the re-assignment of two species into this subgenus. In addition, V. bombycina subsp. bolkardaghensis, V. macrostachya subsp. schizostegia and V. fuhsii var. linearis are raised to species rank and the new name V. parsana is proposed for the latter. Molecular dating and ancestral area reconstructions indicate a divergence age of about 9 million years ago and a place of origin on the Iranian Plateau. Migration to the Western Mediterranean region has likely taken place through a North African route during early quaternary glacial times. This study supports the assumption of the Irano-Turanian region as a source of taxa for neighboring regions, particularly in the alpine flora.

3.
Sci Rep ; 9(1): 12991, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506504

RESUMO

Endemism is one of the most important concepts in biogeography and is of high relevance for conservation biology. Nevertheless, our understanding of patterns of endemism is still limited in many regions of high biodiversity. This is also the case for Iran, which is rich in biodiversity and endemism, but there is no up-to-date account of diversity and distribution of its endemic species. In this study, a comprehensive list of all endemic vascular plant species of Iran, their taxonomic composition and their geographical distribution are presented. To this end, a total of 2,597 (sub)endemic vascular plant species of Iran were documented and their distribution in three phytogeographical regions, two biodiversity hotspots and five areas of endemism were analysed. The Irano-Turanian phytogeographical region harbours 88% of the Iranian endemics, the majority of which are restricted to the Irano-Anatolian biodiversity hotspot (84%). Nearly three quarters of the endemic species are restricted to mountain ranges. The rate of endemism increases along an elevational gradient, causing the alpine zone to harbour a disproportionally high number of endemics. With increasing pastoralism, urbanization, road construction and ongoing climate change, the risk of biodiversity loss in the Iranian mountains is very high, and these habitats need to be more effectively protected.


Assuntos
Biodiversidade , Evolução Biológica , Conservação dos Recursos Naturais , Ecossistema , Modelos Teóricos , Traqueófitas/classificação , Geografia , Irã (Geográfico) , Especificidade da Espécie , Traqueófitas/fisiologia
4.
Sci Rep ; 8(1): 10345, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29985437

RESUMO

Conservation biology aims at identifying areas of rich biodiversity. Currently recognized global biodiversity hotspots are spatially too coarse for conservation management and identification of hotspots at a finer scale is needed. This might be achieved by identification of areas of endemism. Here, we identify areas of endemism in Iran, a major component of the Irano-Anatolian biodiversity hotspot, and address their ecological correlates. Using the extremely diverse sunflower family (Asteraceae) as our model system, five consensus areas of endemism were identified using the approach of endemicity analysis. Both endemic richness and degree of endemicity were positively related to topographic complexity and elevational range. The proportion of endemic taxa at a certain elevation (percent endemism) was not congruent with the proportion of total surface area at this elevation, but was higher in mountain ranges. While the distribution of endemic richness (i.e., number of endemic taxa) along an elevational gradient was hump-shaped peaking at mid-elevations, the percentage of endemism gradually increased with elevation. Patterns of endemic richness as well as areas of endemism identify mountain ranges as main centres of endemism, which is likely due to high environmental heterogeneity and strong geographic isolation among and within mountain ranges. The herein identified areas can form the basis for defining areas with conservation priority in this global biodiversity hotspot.

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