Rare species of psammophyte flora in transboundary areas of Southern Siberia and Mongolia

Abstract

Data on distribution of 3 rare species which occur in sandy arrays of cross-border territories of Southern Siberia and Mongolia are provided: Iris psammocola, Iris loczyi (Iridaceae) and Vicia tsydenii (Fabaceae), a brief characteristic of their cenopopulation is given.The originality of the plant communities which occur in sandy arrays allows a number of authors to distinguish them as special florocenotype-psammophyton (Psammophyton) [1]. The structure of vegetative cover of sandy arrays considerably depends on the relief and degree of the substrate coherence [2]. In the south of the Tuva Republic in the reserved area "Ubsu-Nur Depression" the cluster of "Tsuger-Els" was investigated. It represents a sandy mane extended from the northwest to the southeast along the left riverbank of the Tes-Hem. To the northwest of mane there is big fresh lake Tore-Hol. Within the cluster a wavy undulating land prevails. The total area of Tsuger-Els sands covers about 60 km². Similar arrays proceed also in the territory of Mongolia -the Altan-Els sands entering the largest array Borig-Del. The cluster belongs to Ubsunursky plain desert-steppe province [3]. In 2005 in the territory of Tsuge-Els cluster a new species for the flora of Russia -Iris psammocola Y.T. Zhao was found [4]. The species has obconical rhizome, flowers on short peduncles which are inside the curtain is characteristic of this species, is on 2 pedicel lanceolate webbed spata are available for each flower, the perianth tube is thin funnelshaped, many times exceeds the ovary at length, the flowers are sulfur-yellow. In 2013 in the neighborhood of lake Tore-Hol we also found this species: "Republic of Tuva, Erzinsky district, lake Tore-Hol neighborhood, Tsuger-Els sands, N 50˚09.231 'E 95˚12.751', H=1200 m, 6.06.2013. The plants occur in different plant aggregations of small structure and the rarefied herbage, at the same time the projective covering makes about 20% in cenopopulation: Thymus mongolicus (Ronn.) Ronn. -sp., Carex sabulosa Turcz. ex Kunth -sol., Agropyron desertorum (Fisch. ex Link) Schult.sp., Thesium tuvense Krasnob. -sol., I. psammocola -sol.; in some about 30%: Alissum lenense Adams -sol., Th. mongolicus -sol., Artemisia sp. -sol., Oxytropis tragacanthoides * Corresponding author: norbo@ngs.ru

New Approach to the Systematics of the Section Psammiris (Iris, Iridaceae): What Does Chloroplast DNA Sequence Tell Us?

“…The northernmost wild locality of I. potaninii known to us has been recorded from the upper Barguzin Depression in the Republic of Buryatia, Russia (54°27′16.5″ N 110°27′08.8″ E; see , accessed on 20 December 2022). As reported in [ 56 ], its range covers southern Mongolia from the Gobi-Altai Mountains, Bayankhongor Aimag (e.g., HAL0040724 and HAL0048583; see [ 103 ]), and the Gurvan Saikhan Mountains, Ömnögovi Province [ 118 ], to western Inner Mongolia and the Ningxia Hui Autonomous Region, China. It often grows in dry rocky, gravelly, or sandy places and on steppe slopes, dunes, and along perennial streams at elevations of 550–2800 m.…”

“…arenaria Doronkin, described from Kyakhtinsky District, southern Republic of Buryatia, Russia [ 11 ], was synonymized with I. psammocola [ 55 ]. Subsequently, I. psammocola was reported from the Altan-Els sand dune region of the Borig-Del-Els sandy areas, the Mongolian part of the Uvs Lake Basin [ 56 ]. It was asserted that I. psammocola occurs only on sandy arrays and has a disjunctive distribution range in Central Asia [ 55 , 56 ].…”

“…Subsequently, I. psammocola was reported from the Altan-Els sand dune region of the Borig-Del-Els sandy areas, the Mongolian part of the Uvs Lake Basin [ 56 ]. It was asserted that I. psammocola occurs only on sandy arrays and has a disjunctive distribution range in Central Asia [ 55 , 56 ]. It is a relative of I. potaninii and has a chromosome number of 2 n = 22 [ 55 ].…”