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The locality of Potamogeton berchtoldii Fieber, the new species to the flora of Tajikistan (Middle Asia), together with its ecological conditions are presented. Additionally, the list of herbarium specimens of P. pusillus L. s. stricto gathered in Tajikistan and few specimens of P. berchtoldii collected from the area of adjacent countries are also provided. Taxonomical position of the species within the Potamogeton pusillus aggregation, the main morphological features of both taxa and possibility of finding other localities are discussed.
The aim of this study was to identify cyanobacteria diversity in rock communities from the cold desert ecosystem in Eastern Pamir Mountains (Tajikistan) and assess if the rock type and rock`s porosity can be indicators of microbial diversity in this extreme environment. Seven samples were collected in July 2015 from hillsides (ca 4000–4500 m a.s.l.) of the Eastern Pamir Mountains. Petrographic and scanning microscopy (SEM) allowed for the characterization of the rocks inhabited by endolithic communities as granite, gneiss and limestone with variable porosity. Based on next-generation sequencing (NGS) of amplicon of V3–V4 hypervariable region of 16S rRNA gene, we established that Actinobacteria,Proteobacteria and Cyanobacteria dominated the endolithic communities of microorganisms in the rocks studied, which distinguishes these communities from those described for other cold arid regions. Chroococcidiopsis and Leptolyngbya were dominant genera in the cyanobacterial communities according to culture-dependent analysis, as well as microscopic analyses of endoliths scraps from the rocks. Culture-independent metagenomic analyses revealed that Microcoleus, Acaryochloris, Chroococcidiopsis and Thermosynechococcus reads were the most abundant from all reads and dominated interchangeably in the samples. Endolithic communities of microorganisms in the rocks from the cold desert shrubland of Eastern Pamir Mts. appear to be diverse and different from communities described for other cold deserts.
Furcophyllia is an unusual coral with septa regularly splitting into branching sets called septal brooms. This pattern of septal apparatus is so alien to scleractinians, that, despite a trabecular microstructure of septa resembling that of the Scleractinia, the genus was originally ascribed to a rare group of corals informally referred to as sleractiniamorphs, previously known from the Ordovician and Permian. Genus Furcophyllia emerged together with corals of several groups, after the post−Permian crisis diversification of skeletonized anthozoans, some of them markedly differing in their skeletal features from typical Scleractinia. So far, the genus was represented by middle Carnian Furcophyllia septafindens from the Dolomites, in the Southern Alps. Here, we report Furcophyllia shaitanica sp. nov. from limestone boulders found in the volcano−clastic deposits of the upper Ladinian Šajtan suite of the South Eastern Pamirs. A new species of Furcophyllia signifies that the genus was a faunal element widely distributed in the Tethys.
This paper discusses the floristic structure, distribution and habitat requirements of a new aquatic syntaxon, Stuckenietum amblyphyllae ass. nova. Patches of the Stuckenietum amblyphyllae association occur in the Pamir Alai Mountains in Middle Asia (Tajikistan). The biotope of this community represent high mountain rivers and ponds at the bottom of glacial river valleys situated at elevations between 1900 and 3800 m. Patches of the Stuckenietum amblyphyllae association are characterised by a clear predominance of the typical species, i.e. Stuckenia amblyphylla, which occupies an aerial extent of between near 40 up to 90% of the surface studied. Patches of the community are poor in species, comprising a maximum of five taxa. Among associated species mainly rush, aquatic, meadow and marsh taxa have been noted. The Stuckenietum amblyphyllae community prefers cold, open, alkaline waters with medium flow-rate, ranging in depth from 15 to 75 cm. It is also, but rarely, found in the mountain ponds. Together with the Stuckenia filiformis community it designates in the Pamir Alai Mountains the upper limit of aquatic vegetation.
Dionysia involucrata Zaprjag. (Primulaceae) is known as critically endangered endemic species of Hissar Mountains in Tajikistan. It is reported from few localities mainly in Varzob River valley and its tributaries. The species inhabits steep or overhanging faces of granite rocks in narrow river gorges. During the research all known populations of D. involucrata were examined in respect of the habitat conditions and species composition of vegetation plots. We analyzed the population extent of the species in its range in Tajikistan and the main threats in order to assess its conservation status. The detrended correspondence analysis was performed on a matrix of 65 relevés and 49 species (vascular plants and mosses), to classify the phytocoenosis with domination of D. involucrata according to their floristic composition in relation to other petrophytic vegetation units. Using our field data regarding present extent of occurrence and area of occupancy we conclude that the threat category of D. involucrata should be reassessed from critically endangered to endangered. The species shows decline tendency in extent of occurrence, area of occupancy as well as in number of locations. The vegetation plots with domination of D. involucrata have relatively high level of separateness due to different species composition. We define the new association – Dionysietum involucratae – representing chasmophytic vegetation of submontane and montane zone in Middle Asia (ca. 1000–1600 m a.s.l.). The plots of Dionysietum involucratae were found mainly on granite rocks, on very steep or overhanging faces, on southwestern or southern exposition. The association is rather poor in species with inconsiderable contribution of mosses. Despite the diagnostic species, Campanula incanescens, Carex koshewnikowii and Scutellaria hissarica were the most abundant and frequent taxa within the researched patches of vegetation.
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