Search

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.

Biodiversity loss due to human activities has dramatically increased in the last decades, and attempts to protect threatened species should be accelerated. An important contribution towards this goal is to identify areas rich in biodiversity and endemism, where conservation will be most efficacious. Here, we follow this strategy for Iran, which includes large parts of the Irano-Anatolian global biodiversity hotspot, to assess the extent of conservation gaps. Based on nearly 25,000 records from about 2600 (sub-)endemic vascular plant species, we determine centres of endemism using three well-established biodiversity indices (endemic richness, range-restricted endemic richness, range-rarity richness). Considering only areas (grid cells) where these indices were highest (10%/5%-based quantiles), a total of 74/39 grid cells are identified as Hotspots (centres of endemism supported by at least one index), and 30/18 grid cells are identified as Priority Hotspots (centres of endemism supported by all three indices). All hotspots are inside the Irano-Anatolian biodiversity hotspot and inside previously identified areas of endemism. Although the 10%/5%-quantile-based Priority Hotspots cover only 5%/3% of the Iranian surface area, they contain 59%/47% of the endemic plant species of Iran. Yet, Priority Conservation Gaps (Priority Hotspots not covered by nature reserves) amount to 47%/50% compared to 59%/54% for Conservation Gaps (Hotspots not covered by nature reserves). Evidently, there is a major discrepancy in the Irano-Anatolian biodiversity hotspot between an area being a centre of unique plant diversity and the protection status of this area. Considering the growing pressure on these areas due to, for instance, global climate change or increasing anthropogenic land use, establishment of new nature reserves in both the Conservation Gaps and especially the Priority Conservation Gaps as well as the increased efficacy of the already established nature reserves in the identified hotspots is necessary.

Iran lies within three major phytogeographical regions including the Euro-Siberian, Irano-Turanian and Saharo-Sindian regions. There are many microclimates and ecological niches in different parts of the country especially along the transitional and ecotone zones. The Mediterranean xeric oceanic (Mxo) microbioclimate is a noteworthy climatic condition which covers the lowland areas of the Mediterranean basin and surprisingly occurs also in three small patches in Iran, including the Sefid-Rud valley, southern foothills of Khabr Mountain and several valleys of western Jebal-e Barez Mountain range. The latter region is the subject of the present study. Unexpected occurrences of several Mediterranean species such as Cercis siliquastrum, Myrtus communis, Linaria iranica and Melissa officinalis are confirmed from this region and their distributions are briefly discussed in relation to climatic conditions., Doostmohammadi Moslem, Bordbar Firouzeh, Mirtadzadini Mansour. Floristic composition correlates with bioclimatic condition. Occurrence of several Mediterranean elements in southeast of Iran. In: Ecologia mediterranea, tome 46 n°2, 2020. pp. 27-34.

Pteropyrum is a small genus of Polygonaceae with four species from the arid regions of Iran and adjacent countries. Pteropyrum spp. are not precisely delimitated and are difficult to identify because of their high plasticity in morphological characters. Pteropyrum (C3) has a close affinity to Calligonum (C4) and is therefore a suitable case for C4 evolutionary studies. We investigated the morphology and micromorphology (including pollen morphology) of Pteropyrum and elucidated the phylogenetic relationships with Atraphaxis and Calligonum using nuclear ITS sequences. Characteristics of the photosynthetic tissues such as volume and number of layers of primary carbon assimilation tissues (PCA) and photosynthetic carbon reduction tissue (PCR) were studied. In addition, the leaf and cotyledon anatomical characters of Pteropyrum (C3), Atraphaxis (C3) and Calligonum (C4), and their δ 13C values were compared to look for evolutionary changes in assimilating organs. The molecular phylogenetic tree identifies two strongly supported clades in Pteropyrum and its close relationship with Calligonum, confirming previous studies. Some morphologically similar species belong to different clades, which is probably due to convergent evolution and homoplasy. Leaf anatomical studies show that Atraphaxis has a multilayered mesophyll tissue, whereas Calligonum has one-layered mesophyll cells. The volume and layer number of mesophyll tissue cells decreases, whereas water storage tissue area significantly increases from Atraphaxis to Pteropyrum and Calligonum. This phenomenon confirms previous studies in other lineages with C4 salsoloid anatomy that have evolved through increasing of water storage tissue and succulence of assimilating organs. In the taxonomic part of the paper, a key to identification of accepted taxa of Pteropyrum, description of species and distribution maps are presented based on numerous herbarium specimens and our own rich collections from the field. Four new species are described based on a combination of morphology of seedlings and mature plants, pollen morphology and molecular data. A subspecific classification is suggested to show morpho-geographical variation of Pteropyrum aucheri s.l.

The Zagros is the largest mountain range of the Iranian Plateau stretching from northeast Iraq to south Iran. It has high mountain peaks reaching the subnival zone in different parts though mostly in the central and southern Zagros. The climate is continental and the precipitation regime is Mediterranean with cold and wet winters and warm and dry summers. Our database lists 3642 vascular plant species from this mountain range. The Zagros is totally located inside of the Irano-Turanian biogeographical region and the Irano-Anatolian biodiversity hotspot. More than 70% of the species are Irano-Turanian elements but widespread species occurring in two or several biogeographical regions are also many. This mountain range is identified as an area of endemism and 21% of the entire flora are Zagros elements. The major vegetation types of the Zagros are oak woodlands, Amygdalus-Pistacia shrublands, montane steppe shrublands, wetlands, chasmophytic habitats, subalpine, alpine and subnival zones. Anthropogenic activities are threatening the unique flora and vegetation types of this mountain range and a strong conservation policy is recommended.

The Yazd–Kerman massifs include the poorly known highlands of central and southern Iran reaching to 4465 m a.s.l. at the highest peak. This area belongs to the Irano–Turanian phytogeographical region and 68% of the flora belongs to this floristic region. Total flora of the area is composed of 1308 vascular plant species of which 8% are endemics. The richest genera in terms of endemic species are Astragalus (21 species), Acantholimon (13), Cousinia (8), Echinops (8) and Nepeta (7). Hemicryptophytes (36%) and therophytes (32%) are the most dominant life forms. Several vegetation types are distinguishable in various habitats including halophytic vegetation, Stipa-Artemisia steppes, psammophytic vegetation, shrublands and woodlands, Rheum ribes vegetation, wetland communities, rocky cliff vegetation, subalpine umbelliferous communities and alpine–subnival communities. The protected areas hardly correlate with the biodiversity hotspots in the region and therefore many species are threatened.

Paracaryum lalezarense is described as a new species endemic to the Lalezar Mountains in southeastern Iran. The new species is characterized by its moderately incurved nutlet wings, glochidiate nutlet wing margins, smooth and shiny nutlet disks and rather small flowers (corolla 3.5–4 mm long) with corolla tube as long as limb. It is restricted to high alpine and nival elevations (4,000–4,260 m) that is an infrequent phenomenon amongst other species of the genus Paracaryum. Description, photographs of living plants and distribution map of the new species are provided and taxonomic relationships with its closest possible allied species and its conservation status are briefly discussed.

Lactuca pumila, so far known only from a single gathering from E Afghanistan, is shown to occur also in the SE Zagros range, Kerman province, southeastern Iran. The new locality extends the range of the species about 1000 km south-westward and this disjunction further highlights the floristic link between the SE Zagros and the Hindu Kush as well as Central Asian mountains. Fruiting plants, so far not known of the species, confirm it as a member of the L. rosularis group, which includes four closely related species of rosette herbs confined to rock crevices in the montane to alpine zone of the Iranian–Afghan highlands. The relationships of the two disjunctly distributed populations and of the species is corroborated by a molecular phylogenetic analysis. A key to the species of the L. rosularis group, a full description, photographs of life plants, SEM images of achenes and a distribution map of L. pumila are provided, and the generic classification is discussed.