Зоологический журнал

ADAPTIVE STRATEGIES OF BROWN FROGS (AMPHIBIA, ANURA,

Berman D.I., Bulakhova N.A., Meshcheryakova E.N.

Adaptive strategies of the common frog, Siberian wood frog and Dybovsky's frog (Rana temporaria, R. amurensis, R. dybowskii) in relation to winter temperature was studied. They all tolerate only small negative temperatures in a state of supercooling and die during the next freezing. A threshold of long-term (10 days) tolerated temperatures appears to be similar in all species: only -1.5°C. Solely R. amurensis survive without loss a short period (3 days) at -2.5°C, whereas 50-60% individuals of the other two species perish. But a 10-day long exposure to that temperature is fatal to 90% of sampled Siberian wood frogs as well. The low cold-hardiness of the species in question shows that none of them (including R. amurensis which penetrates most deeply into the Subarctic and Arctic) can overwinter beyond water bodies in areas with grounds that freeze solid. Egg cold-hardiness of all of these species varies little and is low. The clutches that remain freezing outside water for several hours even at negative temperatures close to zero lose 100% embryos. Clutches submerged in water can be completely ice-included, but since even small (about 200 mL) clutches fail to freeze solid at -3°С in two days, some embryos retain viability. The uniform cold-hardiness values obtained for the species under study reflect similar overwintering conditions in water bodies in cold regions, but fail to explain the differences in frog distribution ranges. All frog species that require overwintering in water can be concluded to have low cold-hardiness, whereas those that hibernate on land are cold-resistant to varying degrees.

A NEW AND A LITTLE-KNOWN SPECIES OF THE ORIBATID MITE GENUS

Ermilov S.G.

A new oribatid mite species of the genus Benoibates (Oribatida, Oripodidae) is described from the Antigua Island. Benoibates antiguaensis sp. n. differs from B. muscicola Baranek 1981 by the shorter adanal and noto-gastral setae, and the spiniform anal setae. Benoibates crinitus (Berlese 1910) is redescribed from the U.S.A., based on topotypes.

A NEW SPECIES AND GENUS OF PSAMMOPHILIC PROSERIATA (TURBELLARIA, OTOPLANIDAE) FROM LAKE BAIKAL AND ITS PHYLOGENETIC RELATIONS AS REVEALED BY 18S rRNA SEQUENCE DATA

Lukhnev A.G., Koroleva A.G., Kirilchik S.V., Timoshkin O.A.

An illustrated description of Boreusyrtis maksimovae gen. et sp. n., representative of a new genus of Otoplanidae turbellarians (Proseriata) from Lake Baikal, is given. The worm shows a peculiar pattern of the ciliated epithelium of the rostral body end, the special morphology of the pharynx and copulative apparatus, and the distinguished topography of the sexual organs. A comparative morphological analysis of the Baikal otoplanid and related forms has allowed us to perform their partial taxonomic revision, resulting in the erection of Boreusyrtis Lukhnev et Timoshkin gen. n. Pseudosyrtis neiswestnovae Riemann 1965, from Elba River, closely related to our new species, is also transferred to the new genus, comb. n. A molecular analysis, based on 18S rRNA gene sequence data, has also been performed, and a phylogenetic tree constructed.

BODY AND MOLAR DIMENSIONS IN THE MOLE VOLE

Kropacheva Y.E., Cheprakov M.I., Sineva N.V., Evdokimov N.G., Kuzmina E.A., Smirnov N.G.

Body size and molar (m/1) characters were measured and examined in mole vole specimens obtained from a laboratory colony (n = 35), those captured in nature (Orenburg Region, n = 34; Chelyabinsk Region, n = 42), as well as two fossil series sampled from two Holocene-dated horizons in the Alekseevskaya Cave (n = 51; n = 66). Absolute ages were estimated by molar root length values measured from tooth neck to root ends. These estimates correlated well with age intervals distinguished in the study of animals tagged in natural communities. Specimens from the Alexeevskaya Cave showed individual ages from several months to four years; most of them belonged to one-year animals, while a lesser portion to yearlings. Laboratory animals demonstrated higher molar crown values due to slower teeth grinding, and also longer crown measures. Body dimensions of the Holocene-dated mole voles seem to be virtually the same as in modern animals, based on no differences in molar sizes revealed. However, body sizes and m/1 measurements of material taken from the lab and in nature showed low correlations.

DISTRIBUTION AND ORIGIN OF TWO FORMS OF THE MARSH FROG

Lyapkov S.M., Ermakov O.A., Titov S.V.

The formation of the first populations of the marsh frog (the Pelophylax ridibundus complex) near Petropavlovsk-Kamchatski and in the Paratunka river valley must have been the result of human introduction in the late 1980's. At present, more than 20 localities of this species are recorded in Kamchatka. For a more precise definition of the taxonomic status of P. ridibundus sensu lato, samples from 5 populations (altogether, 30 individuals) from southeastern and central Kamchatka are analyzed using molecular methods. In all frogs, the mitochondrial DNA type specific for the "eastern" form (= the Anatolian P. cf. bedriagae), but not for the "western" form (= the Central European P. ridibundus ), is revealed. However, the results of nuclear DNA analysis of marsh frogs from Kamchatka reveal alleles specific for both of the forms, "eastern" and "western", with a frequency ratio of about 2 : 1. The results of sequencing the mitochondrial ND2 gene and nuclear SAI-1 gene suggest that "ancestor" individuals might have been introduced to Kamchatka from the Volga-Don in-terfluve or Ciscaucasia. The absence of both haplotype and nucleotide diversity in the samples studied suggests a single successful introduction that involved a low number of frogs stemming from a single locality.

INNERVATION OF UNPAIRED BRANCHIAL APPENDAGES IN THE ANNELIDS

Tzetlin A.B., Zhadan A.E., Vortsepneva E.V.

Innervation of unpaired branchial appendages is studied using confocal laser scanning microscopy in two annelid species: Terebellides cf. stroemii (Trichobranchidae) and Cossura pygodactylata (Cossuridae). The bran- chial filament is shown to be innervated by one unpaired segmental nerve coming from the ventral nerve cord at the level of chaetiger 2 in C. pygodactylata. This nerve goes transversally along the body wall and comes to the base of the branchial filament from the side. This allowed us to conclude that (1) the branchial filament is unpaired in structure, neither representing merged paired branchiae nor related in its origin with prostomial appendages, nor with peristomial ones; and (2) the branchial filament is the result of a shift of one of the paired segmental branchiae with parallel reduction of the second branchia in this pair. The branchial organ of T. cf. stroemii is innervated by paired segmental nerves from the first and second chaetigers. The segmental nerves are connected by longitudinal nerves going on lateral sides of the body closer to the dorsum. One nerve on each side proceeds to the anterior part of the branchial stalk and another nerve to the posterior part. All these nerves are linked by transversal connections. The anterior stalk nerves come into the anterior branchial lobes, while the posterior nerves to the posterior lobes. In the branchial lobes, the main nerves give rise to thinner ones which go to each of the branchial lamellae. The present study confirms a paired nature of the branchial organ of Terebellides and its origin from two pairs of segmental branchiae.

(KISER 1948) (CLADOCERA, CHYDORIDAE) FROM THE PRIMORSKY TERRITORY: THE FIRST RECORD OF THE GENUS FROM RUSSIA

Garibian P.G.

For a long time did the Far East remain among the least explored regions of Russia. Recent studies, however, demonstrate a special fauna of Cladocera in this region. Nicsmirnovius eximius found in samples from Lake Khanka (Primorskiy Territory) is the first record of the genus from Russia. Further records of taxa from a southern thermophilic complex can be suggested there in the future.

ON THE IDENTITY OF GREY VOLES (CRICETIDAE, RODENTIA) FROM THE BOLSHOI SHANTAR ISLAND, SEA OF OKHOTSK, WITH GROMOV''S VOLE

Dokuchaev N.E., Sheremetyeva I.N.

The identity of grey voles from the Bolshoi Shantar Island with Gromov's vole from the mainland is confirmed using molecular data. The increased diversity of East Asian voles in the "Shantar corner" of the Sea of Okhotsk might be accounted for by counter range expansions of the "southern" and "northern" vole forms in different periods of the Late Pleistocene and Holocene. Their modern marginal populations in the territories studied can therefore be regarded as being relict in character.

PLASTICITY OF THE POLYP''S RESPONSE TO ENVIRONMENTAL CUES REGULATES THE LIFE CYCLE OF

Sukhoputova A.V., Kraus Y.A.

Populations of the scyphozoan jellyfish, Aurelia aurita are widely distributed throughout the world while each local population is adapted to a particular pattern of seasonal change in environmental conditions. It is thus reasonable to suggest that phenotypic plasticity plays important roles in the polyp's response to environmental change. We aimed at studying the influence of habitat-specific conditions on the sensitivity of A. aurita polyps to environmental cues acting as signals for polyp-to-jellyfish transformation, the so-called strobila-tion. We showed that the contribution of phenotypic plasticity to the polyp's response to environmental change was surprisingly high. When two laboratory cultures of Aurelia polyps originating from different geographic regions were reared under the same conditions for about a year, they demonstrated very similar shifts in their responses to environmental cues. Moreover, long-term changes in the rearing temperature affected the sensitivity of the polyps to a temperature drop which is well known as a natural inducer of strobilation.

POSTJUVENILE MOULT IN THE COMMON CROSSBILL

Noskov G.A., Rymkevich T.A., Smirnov E.N.

Common Crossbills are known to start breeding for the first time before they have completely moulted to adult plumage. These breeding crossbills may retain a considerable proportion ofjuvenile (streaked) feathers, and bear two or even three generations of feathers. The questions therefore arise: what is the reason for such high variation in plumage condition; how much is it related to a bird's timing of birth; what is the timing of a moult; and how does it influence the subsequent phases of the annual cycle? The study is based on the results of in vivo examinations of the birds captured at the Ladoga Ornithological Station and in St. Petersburg suburbs (1482 birds), as well as the results of experimenting with juveniles captured from the wild (48) and with pulli (6) of laboratory-bred crossbills. According to trapping data, the moult season lasts from the end of the first ten days of August until mid-November, whereas the majority of birds start moulting for 1.5 months between August 15 and October 1. The timing of postjuvenal moult proves to be far more constant than that of hatching, where variation may be up to 7.5 months. Experiments with a photoperiodic control of the postju-venile moult demonstrate that species-specific features in the Common Crossbill are a quite definite age at which the moult begins (50 days at min and 120-180 days at max) and a rather narrow postjuvenal moult interval with a short day length (14.5-13 h to 10-9 h of daylight) within which the moult is controlled by a PP-response. This synchronization of the moult onset is a direct consequence of the very high maximum age and the very short day length at the upper threshold of the photoperiodic interval: as long as there is more than 14.5 h of daylight, no moult would begin until an age of 4-6 months. The individuals that moult within the PP-interval thresholds replace plumage at a high rate. After the day length gets below the lower threshold of the PP-interval, an inhibiting role of the photoperiodic response is activated, terminating the moult in the birds that started moulting too late, while their plumage mainly retain juvenile generation feathers. The annual cycle of seasonal events in the Common Crossbill has some distinctive features, although resting on the common structure of avian annual cycles. One of such features is that sexual activity begins under short daylight conditions if a bird finds itself in an area with abundantly fruiting spruce or larch trees. Another feature of the species' annual cycle is multiple migration activity. The third distinctive feature is a strictly autumnal postjuvenal moult season, with short daylights. It is in this period that an individual's annual cycle gets synchronized with the phenological conditions in the environment and in the population.

(SCHULTZE 1851) AND

Rogozin A.G.

Two species of Turbellaria (Neorhabdocoela Typhloplanidae) new to the fauna of the Urals were found in Lake Bolshoe Miassovo, southern Ural Mountains: Olisthanella obtusa (Schultze 1851) and Opistomum arsenii Nasonov 1917. Both of these species are redescribed and illustrated, and new data on their biology and distribution presented. Both are recorded east of the Volga River for the first time

SP. N. (NEMATODA, MONONCHIDA) FROM SOILS IN THE ROSTOV REGION

Shmatko V.Y., Tabolin S.B.

An illustrated description is given of a new nematode species, Clarkus bulyshevae sp. n., from soil samples taken on the Vodnyi Island, Lake Manych-Gudilo, Rostov Region. Clarkus bulyshevae sp.n. is close to C. pulcherimus Andrdssy 1985, C. elongatus Jairajpuri & Khan 1977, C. sheri (Mulvey 1967) Jairajpuri 1970, C. macropapillatus (Mulvey 1967) Jairajpuri 1970, C. sveltus (Altherr 1968) Jairajpuri & Khan 1982, and C. dorsalis Yeates 1992, but differs by the position of the vulva and the tail length to anal width ratio. The male of Clarkus bulyshevae sp. n is easily distinguished from other species of the genus Clarkus by the presence of 28 supplements at the caudal end of the body.

A TYPIFICATION OF URBAN HABITATS, ANT COMPLEXES OF MOSCOW CITY TAKEN AS AN EXAMPLE

ПУТЯТИНА Т.С., ПЕРФИЛЬЕВА К.С., ЗАКАЛЮКИНА Ю.В.

Проведена типизация городских биотопов. При этом городская среда рассмотрена как мозаичное пространство и учтены такие основополагающие параметры, как происхождение биотопа (почвы), флористический состав и структура растительного сообщества, площадь биотопа. Выделено 11 типов биотопов: газоны, агроценозы, ксерофитные и мезофитные луга, бурьяны, бульвары, мелкие деградирующие парки, небольшие угнетенные искусственные парки, ландшафтные парки, лесопарки, техноценоз. Прежде всего, такая классификация удобна для изучения муравьев. В работе описана базовая структура сообществ муравьев большинства типов городских биотопов. Выявлен основной набор видов муравьев Москвы, ранжированный по встречаемости: Lasius niger (87%), Муг-mica rugulosa (44%), М. rubra (33%), Formica cunicularia (11%), M. ruginodis (10%) и др. Согласно результатам исследований, на территориях с древостоем уборка листвы с помощью грабель оказывает негативное воздействие на сообщество муравьев: снижаются численность, биомасса и видовое разнообразие. Выявлено наиболее устойчивое в условиях Москвы двувидовое сообщество муравьев, которое мы назвали "городским сообществом". Оно состоит из L. niger и М. rugulosa, причем первый вид по численности всегда превосходит второй.

НОВЫЙ ВИД ФОРОНИДЫ PHORONIS SAVINKINI SP. N. ИЗ ЮЖНО-КИТАЙСКОГО МОРЯ И АНАЛИЗ ТАКСОНОМИЧЕСКОГО РАЗНООБРАЗИЯ PHORONIDA

ТЕМЕРЕВА Е.Н., НЕКЛЮДОВ Б.В.

Форониды - тип морских беспозвоночных животных, имеющих всесветное распространение. В настоящее время мировая фауна форонид насчитывает всего 14 видов, однако, их число, по-видимому, гораздо больше, о чем свидетельствуют результаты исследований последних лет. Изучены морфология и микроскопическая анатомия нового для науки вида форонид - Phoronis savinkini sp. n., собранного в Тонкинском заливе Южно-Китайского моря. Форониды образовывали плотное поселение на глубине 2 м, на скальном грунте, покрытом мягким осадком. Воротничок в основании щупалец отсутствует, что позволяет отнести исследуемый вид к роду Phoronis. Лофофор спиральный с одним оборотом, число щупалец 154(160). У всех исследованных экземпляров специализированные половые железы в кроне щупалец отсутствуют. Продольная мускулатура кустистого типа, максимальное число лент продольной мускулатуры 49. Метанефридии с сильно изогнутым выделительным каналом, имеются две ресничные воронки: маленькая - анальная и большая - оральная. Имеются 2 гигантских нервных волокна диаметром 2-5 мкм. Сравнительный анализ морфологических признаков, используемых в таксономии форонид, показал, что морфология форонид из Южно-Китайского моря наиболее сходна с морфологией Phoronis hippocrepia Wright 1856, для которого описаны две морфы - одна обитает в твердых грунтах, другая - на мягких субстратах. Однако между двумя видами имеются существенные морфологические различия в строении лофофора и выделительных органов. Кроме того, у Phoronis savinkini sp. n. отсутствует забота о потомстве, характерная для Pho-ronis hippocrepia. Кладистический анализ таксономического разнообразия форонид позволяет сделать вывод, что разделение форонид на сверлящих и роющих, которое раньше рассматривалось лишь как экологический нюанс, является важным таксономическим критерием. Роющие и сверлящие форониды разошлись, вероятно, давно, и их основными различиями можно считать тип мускулатуры и число ветвей канала нефридия. Показана монофилия рода Phoronopsis и парафилия рода Phoronis. Выдвинуто предположение, что вид Phoronis ovalis является вторично упрощенным. Предложено выделение отдельной клады, включающей виды Phoronis pallida и Phoronis embryolabi.The Phoronida is a phylum of marine invertebrates with worldwide distribution. At present there are 14 species of phoronids in the world fauna, but this number may increase, based on the latest research. In the present study, the morphology and microscopical anatomy of a new phoronid species, Phoronis savinkini sp. n., from the Gulf of Tonkin in the South China Sea are studied. The new phoronid species forms highly dense populations on a rocky ground covered with soft sediment at a depth of 2 m. As an epidermal collar at the base of the tentacles is absent, we refer this species to the genus Phoronis. The lophophore is a one-coil spiral in shape. There are 154 (160) tentacles. Special reproductive glands in the lophophoral cavity are absent. Longitudinal muscle bundles are of the bushy type. The maximum number of bundles is 49. Each metanephrid-ium has a strongly curved excretory canal and two funnels: anal (small) and oral (large). There are two giant nerves of 2-5 micrometers in diameter. A comparative analysis of the morphological characters used in phoronid taxonomy shows that the morphology of the new phoronid species from the South China Sea seems to be the most similar to that of Phoronis hippocrepia Wright 1856, which has two morphs, one burrowing in a hard ground, the other living in soft substrates. However, there are significant morphological differences between the two species: a fundamentally different type of lophophore organization, a different type of excretory organs' organization (including the structure of the nephridial funnels), and the absence of reproductive glands in the crown of tentacles in the new species. A cladistics analysis of phoronid taxonomic diversity shows that the ecological division of phoronids into two groups (burrowing and living in soft substrates) is meaningful taxonomically as well. Burrowing and digging phoronids might have diverged long ago. The muscle type and the number of branches of the nephridial canal can be considered as the main differences between the two groups. In the present paper, the monophyly of the genus Phoronopsis and the paraphyly of the genus Phoronis are shown. Secondary simplification of Phoronis ovalis is assumed. A separate clade that includes Phoronis pallida and Phoronis embryolabi is suggested.