Exact reference to hardcopy publication: Kosterin, O. E. 2004. Some Odonata collected in Aldan Ulus of Sakha (Yakutia) Republic in Late June 2002. Notulae Odonatologicae 6 (3): 27-31.

SOME ODONATA COLLECTED IN ALDAN ULUS OF SAKHA (YAKUTIA) REPUBLIC IN LATE JUNE 2002.

O. E. KOSTERIN

Institute of Cytology & Genetics SB RAS, Lavrentiev ave. 10, Novosibirsk 630090 RUSSIA

e-mail: kosterin@bionet.nsc.ru

Abstract – 13 species were collected in S Yakutia at the towns of Aldan and Tommot. Most of them were confined to peat-moss bogs with open larch stand (loc. ‘mari’) on terraces of the major Aldan River, while the main area of the Aldan Upland seems to be almost devoid of Odonata. The record of the only rheophilic species found, Nihonogomphus ruptus (although not its northernmost record), and of a northern boreal species Somatochlora sahlbergi are new for Yakutia. A list of 32 species presently known for Yakutia is given.

Yakutia (presently the official name of this land is "Sakha (Yakutia) Republic" is a vast (3,103,200 km2) and scarcely populated (about 1 million) region situated in NE Asia and characterized by a severe continental climate (the absolute annual amplitude of temperature reaching 101.8^oC at Verkhoyansk (SUSLOV, 1954)). Most of its territory, except for high mountains of its NE part, is covered by open taiga of low-growing larch (Larix gmelinii) with admixture of pine (Pinus silvestris) and birch (Betula pendula s. l.). The forests exist there in spite of extremely low precipitation (mostly in late summer, annual precipitation ranging from 90 to 300 mm), which is compensated by a low evaporation. The summer is quite short (80-110 days without frost) but sunny and hot (at Yakutsk the average temperature of July is 19^oC,the maximum tempereature registered 38^oC), so many animal species extend more northerly in Yakutia than in West Siberia (SUSLOV, 1954). Rather a high latitude provides a very long daytime in June and July and hence a rapid passing of all phenological phases in the beginning of the summer; the best time to collect almost all insects there is June. These conditions are scarcely suitable for most dragonfly species, so few of them occur in Yakutia. There is no checklist published, but thanks to the activity by BELYSHEV (1973), the founder of Siberian odonatology who worked in Yakutia himself, its odonatofauna has been documented rather completely but hitherto included as few as 30 known species. Most data originate from the plain of Central Yakutia, with its numerous lakes, but there is also information from transpolar regions and from mountainous NE Yakutia (BELYSHEV, 1973) while moderate mountains of S Yakutia remained unexplored. After Belyshev, there was only two works concerning the odonatofauna of Yakutia. FUKUI (1992) reported 17 species for the environs of Yakutsk including Aeshna serrata Hagen, 1856 and Coenagrion ecornutum (Selys, 1872) recorded for the first time for Yakutia. POPOVA et al. (2001) in a note in a local ecological journal reported a finding of "Calopteryx virgo" from SW Yakutia (at the sequence of the subordinate rivers Melyuk - Kil’lemtine - Vakunaika, the Chona River basin, and at the Biryuk River, a left tributary of the Lena; both sites between 61 ^o and 62^o N). In fact, this appeared to be Calopteryx japonica Selys, 1869, that was elucidated upon my request by one of the authors of that paper, Dr. N. Vinokurov (pers. comm.)

On June 18-30, 2002 I managed to visit the Aldan Ulus [District] of Yakutia, namely, the environs of towns Aldan and Tommot (the landscape photographs available at http://pisum.bionet.nsc.ru/kosterin/yakutia), and collected there 12 odonate species. (Note Aldan town is NOT situated on the Aldan River; ‘aldan’ in Yakutian meaning ‘gold’).

The territory around Aldan town which I mostly examined belongs to a gentle Aldan Upland, being a plateau without expressed mountain ranges but supporting groups of mountains protruding above tree line (here at about 800 m above sea level) up to 1300-1600 m above sea level. In the middle of the Upland, more or less around Aldan town, more southerly looking spruce (Picea obovata) forests appear with participation of Siberian stone pine (Pinus sibirica), fir (Abies sibirica), aspen (Populus tremula), silver birch (Betula pendula s. l.) and stone birch (Betula lanata). These forests reflect a certain local climatic optimum and somewhat resemble the dark-needle taiga of South Siberia, being isolated from them in the south by the large upland of Stanovoi Range, covered with larch taiga. There are numerous small rivers and rivulets, fast and cold, flowing among gentle mountais of the Aldan Upland. Depressions of many of their valleys as a rule accumulate cold air and provide a microclimate too harsh for tree stands to exist, so these rivers wander over treeless bogs and damp meadows without steady beds. Moreover, most of the rivers have been destroyed by mechanical gold dragging. There are no lakes, except for some bog pools, artificial reservoirs and pools accumulated in old pits. I examined a large pond on the Orto-Sala river within the town, constructed after gold dragging had taken place and nowadays surrounded by grass and bush vegetation, and a smaller pond on the Tamarak River 5 km N of Aldan, surrounded with rich grasses.

For 8 days of intense dragonfly collecting around Aldan town, I collected only one odonate individual, a male of Coenagrion lunulatum (Charpentier, 1840) at the forest edge on a hill just north of the town (125^o22’30’’ E 58^o36’30’’, ~720 m above sea level) on June 19, 2002. At both ponds examined not a single dragonfly was found, although there were lots of Trichoptera and Plecoptera in the surrounding vegetation.

The Aldan Upland is bordered on the west and north by the great Aldan river, a main tributary of the Lena River. At Tommot town the river is still in its upper reaches but is already large and powerful. It has clean cold water (although the fish population is said to have been depleted dramatically, thanks to the gold dragging on its tributaries) and shingle banks. On either of its banks there occur wide terraces occupied by specific NE Asian communities called ‘mari’: open stands of depressed larch on peat-moss bogs with dense Ledum palustre in the understorey and with numerous pools narrowly rimmed with some sedge. There are also larger oxbow lakes, surrounded by willows, birches, hairy alder ( Alnus hirsuta) and bushes of dwarf alder (Duschekia fruticosa) These terraces are bordered by limestone mountains with larch/pine forests. Where the mountains come closer to the river banks, there appear stripes of spruce forests. Observations were made during June 23-25 on the Aldan River left bank 7-9 km upstream of Tommot town: 126^o11’ E 59^o00’40’’ N, about 280 m above sea level; all collections were made on June 24, except for N. ruptus collected on June 25 and Lestes sponsa collected on June 25 in a somewhat different locality: within Tommot town.

L e s t i d a e:

- Lestes sponsa Hansemann, 1823– 1 ♀ collected within Tommot town on June 25

C e n a g r i o n i d a e:

- Coenagrion johannsoni (Wallengren, 1894) – 1 ♂ plus several tandems observed visually on small pools on a large peat-moss bog.

- Coenagrion hastulatum (Charpentier, 1825) – 1 ♂, together with the previous species.

- Enallagma cyathigerum antiquum Bartenev, 1956 – 10 ♂ 4 ♀ on cotton plus about 30 specimens of both sexes in alcohol. These damselflies occured on peat-moss bogs, were common in sedge along larger oxbow lakes and extremely abundant in grass on edges of birch/spruce forest approaching the Aldan River bank. Most of the specimens had the black lateral stripes on the abdomen, variable in expression, in some reduced to short streaks. These stripes are characteristic for the taxon antiquum Bartenev, 1956 ranging in NE Asia. Males of this taxon (including all males collected in the Aldan River valley) have the appendages superiores as in the nominotypical cyathigerum Charpentier, 1840 (with the yellow ‘lip’ protruding behind, not inwards and below as in the Central Asian / South Siberian subspecies E. c. risi Schmidt, 1961). Hence, antiquum may represent no more than a climatic modification of the nominotypical subspecies. Here it is treated as a subspecies preliminarily. Two oldest available species group names proposed for this taxon were published in the same collected paper edition (BARTENEV, 1956; BELYSHEV, 1956): antiquum Bartenev, 1956 and continentale Belyshev, 1956. According to the new International Code for Zoological Nomenclature (1999), Art. 24.1, of two names simultaneously proposed and later considered as synonymic, automatically valid is that was proposed a higher rank taxon. Therefore, Bartenev's name has priority although proposed in a wrong subfamily (as "Agrion antiquum") and although the taxon itself is at most a subspecies. The whole long taxonomic history of this confusing taxon will be considered elsewhere.

A e s h n i d a e:

- Aeshna caerulea Stroem, 1783 – 1 ♂ plus other individuals observed flying above pools over a large peat moss (quite common) and flushed from trunks of larches and pines on the bog and on the southern slope of a bordering mountain (several individuals). During the evening, few individuals were observed along forest edges facing the Aldan River bank flying and landing high on tree branches.

G o m p h i d a e:

- Nihonogomphus ruptus (Selys, 1857) – 1 ♀ (teneral), 2 exuviae. Exuviae were found, on June 24 and 25, attached to boulders on a shingle bank, about 1 m off the water. In the hot morning of June 25 at about 10 o’clock we flushed, along a bank section about 1 km long, six tenerals that flew off the river and perched high in trees on the bank terrace. Although still soft and not yet coloured, they were very wary, and we managed to collect only one.

C o r d u l i i d a e:

- Cordulia aenea (Linnaeus, 1758) – 4 ♂ (one on cotton, 4 in alcohol) – males were quite abundant along the banks of oxbows.

- Somatochlora graeseri Selys, 1887 – 4 ♂, along with the previous species and about as abundant.

- Somatochlora exuberata Bartenev, 1910 – 1 ♂, among the other corduliids .

- Somatochlora sahlbergi Trybom, 1899 – 1 ♀, among the other corduliids .

L i b e l l u l i d a e:

- Libellula quadrimaculata (Linnaeus, 1758) - 1 individual observed on a peat-moss bog with depressed larches.

- Leucorrhinia dubia orientalis Selys, 1887 – 6 ♂ 6 ♀, some teneral. Common on banks of oxbow lakes where perched on dry branches; often found on willow bushes and grasses on wide shingle bank of the Aldan.

The specimens will be transferred to Siberian Zoological Museum at Institute of Systemartics and Ecology of Animals, Siberian Division of the Russian Academy of Sciences. Alcohol-preserved specimens of E. c. antiquum were sent for DNA analysis to Drs. R. Stoks and H. Dumont (Belgium), and those of C. aenea to Dr. R. Joedicke (Germany).

Thus, according to our present day knowledge, we have in Yakutia 7 Holarctic species: Lestes dryas Kirby, 1890, Enallagma cyathigerum Charpentier, 1840, Aeshna juncea (Linnaeus, 1758), Aeshna caerulea Stroem, 1783, Ae. subarctica Walker, 1908, Somatochlora sahlbergi Trybom, 1889, Sympetrum danae (Sulzer, 1776); 20 transpalaearctic species: Lestes sponsa Hansemann, 1823, Sympecma paedisca (Brauer, 1877), Coenagrion hylas (Trybom, 1889) (an eastern species with one isolate in Europe), C. johannsoni (Wallengren, 1894), C. armatum (Charpentier, 1840), C. glaciale (Selys, 1872), C. hastulatum (Charpentier, 1825), C. lunulatum (Charpentier, 1840), Erythromma najas (Hanssemann, 1823), Aeshna crenata Hagen, 1856, Aeshna serrrata Hagen, 1856, Epitheca bimaculata (Charpentier, 1825), Cordulia aenea (Linnaeus, 1758), Somatochlora arctica (Zetterstedt, 1840), Libellula quadrimaculata (Linnaeus, 1758), Sympetrum flaveolum (Linnaeus, 1758), S. vulgatum (Linnaeus, 1758), Leucorrhinia dubia (Van der Linden, 1825) s. l. (ssp. orientalis Selys, 1887), L. rubicunda (Linnaeus, 1758) s. l. (ssp. intermedia Bartenev, 1910) and 6 East Palaearctic species: Calopteryx japonica Selys, 1869, Coenagrion lanceolatum (Selys, 1872), C. ecornutum (Selys, 1872), Nihonogomphus ruptus (Selys, 1857), Somatochlora exuberata Bartenev, 1911, S. graeseri Selys, 1887; in total 32 species. Highly probable is also a transpalaearctic Somatochlora alpestris (Selys, 1840), known from the Kolyma River near the eastern border of Yakutia (BELYSHEV, 1973)/

It is evident that in the area considered the dragonflies concentrated in the valley of the great river (although only one species dwells in the river as such) and are almost absent elsewhere. It is hard to say what contribution to their scarcity on the upland has been done by gold dragging, but my observations in Magadan Province and Kamchatka furnish evidence that mountain northern taiga landscapes are almost devoid of dragonflies naturally. So, only peat-moss bogs with larch stand provide a shelter for a considerble dragonfly fauna. It is of interest that these ‘mari’ are favourite habitat not only for dragonflies: there I found also some butterfly species, such as Maculinea teleius, Lycaeides idas s. l., Brenthis ino, Coenonympha glycerion, that southerly, in the mountains of South Siberia, are mostly characteristic of meadow steppe. This fact of changes of habitat from steppes to peat moss bogs in the north-eastern range is well known (KORSHUNOV, GORBUNOV, 1995) and is consistent with the Principle of Habitat Shift by BEI-BIENKO (1966). However, the dragonflies found on pools among peat-moss bogs are those that are well-known to dwell in such a habitat, and no species preferring other habitats elsewhere was recorded on peat-moss bogs.

The area considered in this paper seems to be empoverished in diversity of Odonata even as compared to the more northerly situated (about 62 ^oN) region of Yakutsk, where most of the previous records have been done. That flat region with numerous depressions of recent and extinct lakes, with meadows and steppoids, and cut through by the wide valley of the great Lena River, provides more diverse habitats for dragonflies and damselflies.

No Sympetrum were found, but we should expect at least S. danae which could appear in July. It is of interest that I collected a specimen of C. hastulatum but not C. lanceolatum. In the SE Siberian and the Far East, the former is very scarce while the latter is common (MALIKOVA, 1995), but perhaps in NE Siberia the relation may be opposite. The number of corduliids collected somewhat reflect the relative abundance of their species.

The record of S. sahlbergi is new for Yakutia but to be expected , for it was reported from the Kolyma River at Verkhnii Seimchan not far from Yakutian eastern borders (BELYSHEV et al., 1978). The second new record for Yakutia is the gomphid Nihonogomphus ruptus. However, this is not the northernmost record of N. ruptus, for it was found, as well as Calopteryx japonica, even at 60^oN on the Podkamennaya Tunguska River (formerly the Evenk National Region of Krasnoyarskii Krai Province) (BELYSHEV, 1973; MALIKOVA, 1995).

Acknowledgements – I express my gratitude to Prof. Tomoo Fujioka (Tokyo) for a financial support of the trip, to Dr. N. N. Vinokurov (Yakutsk) for providing information about Calopteryx in Yakutia, and to Natalya Priidak (Novosibirsk) for help in the field and collecting the exuviae of N. ruptus.

Note added in proof - In collections provided by N. N. Vinokurov I recently also found both species firstly reported for Yakutia by FUKUI (1992): C. ecornutum: 2 f, Namtsy, Lena valley, 75 km N of Yakutsk, 18 and 19.07.03, Vinokurov; A serrata: 1 m, Tabokhoi, Vilyui valley, 30 km W of Suntar, 10.08.97, Stepanov.

References – - BARTENEV, A. N., 1956; Proc. Komarov Far Eastern Branch AN SSR, Zoological series, 3(VI): 202-238; - BEI-BIENKO, G. Ya., 1966, Zurnal obshchei biologii, 27: 51-90; - BELYSHEV, B. F., 1956; Proc. Komarov Far Eastern Branch AN SSR, Zoological series, 3(VI): 181-199; - BELYSHEV, B. F., 1973, The Dragonflies of Siberia (Odonata), Vol. 1, parts 1-2, Nauka, Novosibirsk; - BELYSHEV, B. F., BESSOLITSINA, E. P., KOSTINA, N. S., POLYAKOVA, P. E., 1978, In: Chlenistonogie Sibiri (Prov. Biol. Inst., issue 34), Nauka, Novosibirsk, p. 39-46; - FUKUI, M., 1992, Tombo 35: 11-22; - International Code of Zoological Nomenclature, Fourth Edition, 1999, International Trust for Zoological Nomenclature, London; - KORSHUNOV, Yu., GORBUNOV, P. 1995. Dnevnye babochki Aziatskoi chasti Rossii. Spravochnik, Uralian State University Press, Ekaterinburg; - MALIKOVA, E. I., 1995, Strekozy (Odonata, Insecta) Dal’nego Vostoka Rossii, Ph. D. Thesis, Institute of Systematics and Ecology of Animals, Novosibirsk; - POPOVA, L., V., VINOKUROV, N. N., AVERENSKII, A. I. 2001; Severnoe siyanie, No. 14:. 12; SUSLOV, S. P., 1999, Fizicheskaya geografiya SSSR. Aziatskaya chast’. 2^nd edition, Gosudarstvennoe uchebno-pedagogicheskoe iszatel’stvo ministerstca prosveshcheniya SSSR, Moscow.