New moss records from the Republic of Tuva

Summary . Eight new species for the Republic of Tuva were revealed in the author’s herbarium collection: Cal liergon richardsonii (Mitt.) Kindb., Coscinodon cribrosus (Hedw.) Spruce, Hymenostylium recurvirostrum (Hedw.) Dixon, Isopterygiopsis pulchella (Hedw.) Iwats., Loeskypnum badium (Hartm.) H. K. G. Paul, Plagiobryum demissum (Hook.) Lindb., Pseudocalliergon turgescens (T. Jensen) Loeske, Tayloria lingulata (Dicks.) Lindb. Herbarium labels are quoted, and the distribution features of the species are discussed. The same for the three species which previously were known in the Republic of Tuva by single specimens – Fissidens osmundoides Hedw., Pseudocalliergon trifarium (F. Weber et D. Mohr) Loeske, Indusiella thianschanica Broth. et Müll. Hal. The last species is in the Red Data Book of the Russian Federation


Introduction
The Republic of Tuva is one of the largest republics in Russia. It extends from north to south between 53°43′N and 49°47′N and borders Mongolia to the South. It is between 88°47′E and 99°16′E in longitude and borders the Republic of Altai in the West and the Republic of Buryatia in the East. The territory is geomorphologically heterogeneous: vast intermountain basins combine with ridges and plateaus. The highest point is Mongun-Taiga Mts -3976 m a. s. l. The Republic of Tuva is characterized by an increased continental climate compared with the adjoining regions of Siberia. South Tuva Mountains are the watershed between the river basin of the Arctic Ocean and the drainless region of Central Asia. This watershed is the southern limit for the Siberian taiga landscapes and the northern one for the desert-steppe landscapes of Mongolia. In phytogeography terms, the mountain range of southern Tuva marks the border of the Boreal and ancient Mediterranean floristic sub-kingdoms of the Holarctic (Takhtajan, 1986).
It is surprising, but today the Republic of Tuva is one of the biggest bryological "white spot" of Russia. For this vast and heterogeneous territory, there is the only one list of local bryoflora, for the Todzha Valley (Otnyukova, 2003). Additionally, for some species it is possible to find information about their locations in the territory (Bardunov, 1972(Bardunov, , 1974. To fill the gap some keyplots were investigated recently and about 50 species were revealed as new for the territory immediately, among them so interesting as Amblyodon dealbatus (Hedw.) P. Beauv., Catoscopium nigritum (Hedw.) Brid., Tortella spitsbergensis (Bizot et Thér.) O. Werner, Köckinger et Ros and others (Pisarenko, 2013(Pisarenko, , 2018Pisarenko, Artemov, 2019); and also species from the Red Data Book of the Russian Federation -Aongstroemia julacea (Hook.) Mitt. (Bardunov, 2008), Hilpertia velenovskyi (Schiffn.) R. H. Zander. (Czernyadjeva et al., 2008). The paper continues the list of new findings.

Materials and methods
The work is based on the materials of the author collected in 2013 and 2018-2019. The specimens examined are deposited in the Central Siberian Botanical Garden (NSK), duplicates are in the herbariums of the Altai State University (ALTB) and Moscow State University (MW). The location coordinates are determined using a 12-channel GPS and are given in decimal degrees. The names of moss species are mainly according to the "Check-list of mosses of East Europe and North Asia (Ignatov et al., 2006); names of vascular plants are according to the "Check-list of the flora of Asian Russia" (Konspekt flory ..., 2012). Calliergon richardsonii is obligate swamp species. It is distributed mainly in the arctic and subarctic zones; in the boreal zone it is known from a few localities (Lapshina, 2003;Ignatov, Ignatova, 2004); in south it rarely occurs in the mountains from South Europe (Hodgetts, 2015) to Caucasus (Ignatov, Ignatova, 2004) and Mongolia (Tsegmed, 2010). In Altai-Sayan region the species is rare; there are a few records for Altai (Ignatov, 1994), for Khakassia and for the ranges of the West and East Sayan within the Krasnoyarsk Territory and the Irkutsk Province (Bardunov, 1974). The species prefers xeric habitats and has wide but disjunctive distribution in the Holarctic. In Russia it is known from scattered localities from Kola Peninsula to South Kuril Islands by way of the Caucasus, Transbaikalia, Yakutia and Kamchatka (Ignatov et al., 2017; Herbarium specimens of Russian mosses, URL: http://arctoa.ru/Flora/basa. php). The species is distributed in many regions of Mongolia (Tsegmed, 2010), but in Altai-Sayan region it was reported only from Altai Mts (Ignatov, 1994). The species is widely distributed in most areas of the Holarctic. It occurs mainly in the mountains and grows on wet rocks, more often on limestone. In Siberia it reaches the high Arctic: is known from the Taimyr Peninsula, from the Yakut Arctic, and from the Novosibirsk Islands. But it is more common in the mountains of the southern part of the territoryin the Altai, in the Sayan, in the Baikal region (Herbarium specimens of Russian mosses. URL: http://arctoa.ru/Flora/basa.php). It is not rare in Mongolia (Tsegmed, 2010).
The species takes place in most regions of the Holarctic. It is more common in regions with cold and cool climates; it is widely distributed from the tundra zone to coniferous and broad-leaved forests and in mountains. It grows on rotten log in forests and in breaks of grass turf on the soil in tundra, in crevices of rock outcrops and in niches of stone fields. It is rare or absent in arid areas. In Siberia, it occurs from the high Arctic to the Altai and Sayan and is more common in mountainous regions. In Mongolian mountains it is also not rare (Tsegmed, 2010).
The species is widespread mainly in the Arctic and subarctic regions; to the South it occurs sporadically in the high mountains. It grows in mineralotrophic mires and in wet tundra. In South Siberia it is rather rare, known from a few localities in southeast Altai and in East Sayan (Herbarium specimens of Russian mosses. URL: http://arctoa.ru/Flora/ basa.php). In Mongolia for the species there is the only record from the last century (Abramova, Tsegmed 1983).
This arctic-alpine species is rare in Russia and occurs mostly in Siberia, both in Arctic and high mountains; it grows usually in moss-lichen and dryad tundra on soil and gravelly substrates. Plagiobryum demissum is reported for Republic of Tuva Pseudocalliergon turgescens is rather rare arctoalpine species. It is widely distributed in Arctic and Subarctic regions: in Alaska, Canada, Greenland, Scandinavian Mountains; in Russia -from Kola Peninsula to Chukotka, north to Franz Joseph Land and Vrangel Island (Herbarium specimens of Russian mosses. URL: http://arctoa.ru/Flora/basa.php). Farther south it has scattered localities in mountains. In Altai-Sayan region it is known by some samples from Terektinsky and Kurai Ranges in Altai and from Tunkinskiy, Kitoyskiy and Pogranichnyy Ranges in East Sayan (Bardunov, 1974;Ignatov, 1994). There are reports from Mongolian highlands (Tsegmed, 2010). P. turgescens grows in wet habitats -in hollows of mires, near springs and in water of cold lakes. In the Republic of Tuva it is common and dominates in moss cover of highland swamps. The species is distributed in the Arctic and Subarctic and in the highlands of the Northern Hemisphere temperate zone. In Russia it occurs sporadically in the tundra zone and highlands from the Caucasus to Sakhalin and Kamchatka (Ignatov et al., 2018). In Altai-Sayan region it is known from the Kantegirsky, Severo-Chuisky and Big Sayan ranges and Kuznetsk Alatau (Bardunov, 1974; Herbarium specimens of Russian mosses. URL: http://arctoa. ru/Flora/basa.php). There are no reports from Mongolia. The species grows usually in relatively wet, swampy habitats, sometimes along streams.  (Bardunov, 1974). The locality in Yergak-Targak-Tayga Range is specified as "Sistig-Khem River headwaters" (Bardunov, 1974), so it refers to the Republic of Tuva and located the northeast of the territory. That was the only report of the species for the Republic. There are no records of the species from Mongolia. Pseudocalliergon trifarium is distributed in the Holarctic, mainly in the northern regions and in the highlands. It grows in swamps rich in mineral nutrition, often in places of groundwater outlets with a high content of carbonates. In Siberia it is rare. In the West Siberian plain it penetrates south to the southern part of the Great Vasyugan mire; in Altai-Sayan region it is known from a few scattered localities in Altai, Kuznetsk Alatau and Salair (Ignatov, 1994;Pisarenko, 2014). In Republic of Tuva the species first time was recently reported from Sangilen (Pisarenko, 2013); according to new data it is rather constant component of moss cover in Tuva highland mires.

Indusiella thianschanica
Newly revealed species are different in ecology and area; they belong to different geographical elements. That confirms the thesis of bryological knowledge deficiency for the Republic of Tuva and the need to continue research.