Distribution of millipedes along an altitudinal gradient in the south of Lake Teletskoye, Altai Mts, Russia (Diplopoda)

Abstract The distribution of millipedes along an altitudinal gradient in the south of Lake Teletskoye, Altai, Russia based on new samples from the Kyga Profile sites, as well as on partly published and freshly revised material (Mikhaljova et al. 2007, 2008, 2014, Nefedieva and Nefediev 2008, Nefediev and Nefedieva 2013, Nefedieva et al. 2014), is established. The millipede diversity is estimated to be at least 15 species and subspecies from 10 genera, 6 families and three orders. The bulk of species diversity is confined both to low- and mid-mountain chern taiga forests and high-mountain shrub tundras, whereas the highest numbers, reaching up to 130 ind./m², is shown in subalpine Pinus sibirica sparse growths. Based on clustering studied localities on species diversity similarity two groups of sites are defined: low-mountain sites and subalpine sparse growths of Pinus sibirica ones.


Introduction
This paper continues ecological researches on the Altai millipede fauna in the south of Lake Teletskoye, Russian Altai . Some faunistic records of Sibiriulus altaicus Gulička, 1972 and specimens of the family Diplomaragnidae from the study localities have been made earlier (Mikhaljova et al. 2007. A brief historical account of Altai millipede fauna research can be obtained from the publication of Mikhaljova et al. (2008) and Nefediev and Nefedieva (2013).
Since 1998 the Altai State Nature Biosphere Reserve and a buffer zone around Lake Teletskoye are inscribed as one of three separate areas of UNESCO World Natural Heritage Site under the name of «Golden Mountains of Altai». Lake Teletskoye, being the deepest and the largest body of freshwater in southwest Siberia, exerts a great warming influence on local climate, in its southern part especially. Situated at a height of 435 m above sea level, the lake lies between the mountain ridges of Altyntu and Korbu, and the Chulyshman river highlands in the south.
The aim of our present paper is to explore the distribution of millipedes along an altitudinal gradient in the south of the Teletskoye Lake in the Kyga Biogeocenosis Profile.

Material and methods
Material was collected by the first and the second authors of this article in August 2005 using hand sampling from the litter and standard technique of soil sampling (Ghilarov 1987): 8 soil samples per each studied numbered site, sample area ¼ m 2 , depth 10 cm. The total amount of studied millipedes is 968 specimens.
The Kyga Biogeocenosis Profile was laid in 1959-1961 in the territory of watershed of the Kyga and Bayas rivers in the south of the Teletskoye Lake near the cordon of Chiri, Ulagan District, Republic of Altai, Siberia, Russia. The profile encompasses 22 numbered sites at different altitudes, and comprising relic Pinus sibirica forests from the Tertiary period. Its length is about 12 km, and its altitude ranges from 443 to 2267 m a.s.l. It is begun at the mouth of the Kyga river and ends on the top of the Malaya Koliushta mountain. The vertical vegetation zonation here is characterized by the presence of forest and high-mountain belts. There are widespread dark coniferous forests with Betula pendula and Populus tremula, also called as chern taiga, and sparse growths of P. sibirica in the former belt, whereas alpine meadows do not occur almost at all in the latter. Above the timberline at a height of 2100 m above sea level, all hilltops are occupied by shrub, moss-lichen and rocky tundras.
All sites we collected are listed and described below according to the following standard: site number (bold): GPS (WGS84) position, altitude, habitat, sampling date, sampling methods. The cluster analysis was performed using Statistica 10 (StatSoft 2011). The material treated herein has been deposited mainly in the collection of the Altai State University, Barnaul, Russia (ASU), and partly shared also with the collection of the Institute of Biology and Soil Science, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia (IBSS), as indicated in the text. The species names include the literature references concerning Asian Russia only.
Material examined. 1 male (IBSS), site 9; 3 males (ASU), site 16; 1 male (ASU), site 18. Distribution. This species is characterized by disjunctive area. The first distribution area is in the south of Siberia (Republic of Altai, Republic of Khakassia, southern part of Krasnoyarsk Province, Republic of Tyva) and the second one spreads in the Russian Far East (Maritime Province, southern part of Khabarovsk Province, Amur Area, Jewish Autonomous Area) and North-Eastern China.
Remarks. This species is characterized by euryoky, dwelling in Siberia in herbaceous meadows, small-leaved, mixed and dark coniferous forests, and subalpine meadows and montane tundras, up to 2500 m a.s.l. (Mikhaljova and Nefediev 2003). In the Kyga Biogeocenosis Profile the species is very rare (0.5-1.5 ind./m 2 ), collected from the mid-mountain dark coniferous forest, and also from subgoltsy sparse growths of P. sibirica and mountain tundra with dwarf bushes of B. rotundifolia and S. glauca, with the maximum altitude registered is about 2194 m a.s.l.
Remarks. In the Kyga Biogeocenosis Profile this species dwells in low-and midmountain chern taiga forests, and also subalpine sparse growths of P. sibirica, with the maximum altitude registered is about 1903 m a.s.l.
Material examined. 1 male (ASU), site 1; 1 female (ASU), site 8a. Distribution. The species appears to be quite widespread in the south of Siberia, Russia: Kemerovo Area, Republic of Khakassia, Altai Province, Republic of Altai, southern part of Krasnoyarsk Province, Republic of Tyva, Chita Area. Also it has been recorded in Eastern Kazakhstan and Kyrgyzstan.
Remarks. The species inhabits forest litter of small-leaved, mixed and dark coniferous forests, under bark of logs and trees, and in mosses and mushrooms. The maximum altitude registered is about 1700 m a.s.l. (Mikhaljova and Golovatch 2001). In the Kyga Biogeocenosis Profile the species is very rare collected from low-and mid-mountain chern taiga forest, with the maximum abundance registered is about 1 ind./m 2 . Remarks. It is very likely these females and juveniles appear to belong to S. altaicus or P. amurensis.
Remarks. The species lives in dark coniferous forests up to 1350 m a.s.l. (Mikhaljova and Golovatch 2001). In the Kyga Biogeocenosis Profile the animal prefers midmountain dark coniferous forests at 1100-1414 m a.s.l., when it is very rare, and the numbers range from 0.5 to 1 ind./m 2 . The above material appears to belong to topotypes, and this is the first record of the female specimen in this species.
The numbers of diplopods range from 14.5 to 65 ind./m² in subzones of low-and mid-mountain chern taiga forests, and from 5.5 to 8 ind./m² in high-mountain shrub tundras (Table 1). Despite of the lowest species diversity in subalpine sparse growths of P. sibirica, millipedes show the maximum numbers, reaching up to 130 ind./m² in the old fire-site (site 11), evidently caused by the abundance of plant debris of dwarf vegetation of Betula rotundifolia and Salix glauca that appear to be more suitable for feeding of millipedes than pine litter.
Clustering of investigated sites in the Kyga Biogeocenosis Profile on species diversity allows to grouping at least two obvious sets of sites ( Figure 1). The first group unites low-mountain chern taiga forests (sites from 2 to 7), with altitudes range from 494 to 960 m a.s.l. The second group includes subalpine sparse growths of P. sibirica localities (sites from 10a to 15), and also the highest locality of chern taiga forest (site 10) and a transition locality from subalpine sparse growths to shrub mountain tundra (site 16), with altitudes range from 1468 to 2028 m a.s.l. Some localities of midmountain chern taiga forests and mountain tundras are less similar both to each other and to other groups.
The very interesting situation is observed with two congeners of Julus as regards to altitude distribution, showing competitive relationships to each other. Thus, J. g. ghilarovi is mainly recorded in low-mountain and in the beginning of mid-mountain chern taiga forests, while it almost disappears in subalpine sparse growths of P. sibirica, but it emerges again in rocky mountain tundra on the top of the investigated biogeocenosis profile. At the same time, J. insolitus populates mainly subalpine sparse growths of P. sibirica and lifts up to shrub mountain tundra at 2194 m a.s.l. Taking into account that J. insolitus is very abundant here, we assume it wins the competition and Table 1. Millipede abundance (ind./m 2 ) and hand sampling (+) in the Kyga Biogeocenosis Profile sites investigated. displaces J. g. ghilarovi from subalpine P. sibirica sparse growths. The record of female specimens of J. insolitus is the first one in this species. Both members of Kirkayakidae, K. pallidus and T. montanum, are reported in chern mid-mountain taiga at the highest altitudes for the first time. Also this is the first record of the female specimen in the former species.