Contents of Proceedings of the Zoological Institute

Volume 313 (4), 2009

Date of publication — December 25, 2009

Additions to the Early Cretaceous dinosaur fauna of Transbaikalia, Eastern Russia

Eight dinosaur taxa are currently known from the Early Cretaceous (Barremian-Aptian) Murtoi Formation in the Lake Gusinoe Depression of western Transbaikalia: the theropod Richardoestesia sp.* and indeterminate therizinosauroid, ornithomimosaur and dromaeosaurid material; a titanosauriforme sauropod (cf. Euhelopus), and cf. Mongolosaurus sp.; and an indeterminate ornithopod* and the ceratopsian Psittacosaurus sp. (taxa marked with an asterisk were not reported previously). In the more easterly Chikoi-Khilok Depression the Early Cretaceous (Aptian) Khilok Formation has produced fragmentary remains of four dinosaur taxa: the theropod ‘Prodeinodon’ sp. and an indeterminate dromaeosaurid, an indeterminate titanosauriform (cf. Nemegtosaurus) and an indeterminate ornithopod. The most notable differences between the two faunas are the absence of large carnivorous theropods in the Murtoi Formation and the different composition of the sauropod and, perhaps, the ornithopod faunas in each basin.

A new mite genus Caenolestomyobia gen. nov. (Acariformes: Myobiidae) from marsupials of the genus Caenolestes (Paucituberculata: Caenolestidae)

A new mite genus Caenolestomyobia gen. nov. (Myobiidae: Archemyobiinae) with two new species, C. lukoschusi sp. nov. (type species) ex Caenolestes fuliginosus (Paucituberculata: Caenolestidae) from Ecuador and C. faini sp. nov. ex Caenolestes caniventer from Peru, are described. The new genus differs from other two genera of the subfamily, Archemyobia and Dromicimyobia by the structure of the internal attaching organ of genua I. Additionally, in Caenolestomyobia, setae f2 and h2 are delayed to adults, and in males, setae c2 are located on the genital shield. The new genus differs also from Archemyobia by the presence of lateral notches on the gnathosoma and by the absence of the second claw on tarsi III and IV. It differs from Dromicimyobia by the absence of setae 3b, 3c, 4b, and 4c in males. Species of the new genus differs from each other by the following characters. In males of C. faini sp. nov., setae e1 are 2.1–2.3 times longer than c2, the apices of setae c2 almost reach the level of seta e2 bases; in tritonymphs, setae f1 are shorter than e2, their length ratio is 1: 1.2–1.7. In males of C. lukoschusi sp. nov., setae e1 only 1.1 times longer than c2, the apices of setae c2 far distant from the level of seta e2 bases; in tritonymphs, setae f1 are longer than e2, their length ratio is 1.1–1.4: 1.

Production of late age stages in Oithona similis (Copepoda: Cyclopoida) in Kola Bay (Barents Sea)

The seasonal dynamic of production parameters in copepodites IV–V and adults of the common planktonic crustacean Oithona similis was investigated in Kola Bay of the Barents Sea during 2004–2005. The mean annual abundance was 1565±132 ind m–2. The mean body size increased since December reaching the maximum in May. The maximum egg production rate (1.703 egg female–1 day–1) and specific egg production rate (0.0381 day–1) were recorded in July 2005. Annual integrated production depended on the methods for calculation and varied from 3294 to 9064, averaging 5557±257 ?gC m–2 year–1. The production rates of congeneric species in temperate seas were higher significantly probably due to increased water temperature and favorable food conditions.

Changes of biological communities in the Eastern Gulf of Finland during the last century

Changes in biological diversity of the Neva Estuary (eastern Gulf of Finland), which is one of the largest Baltic estuaries, were assessed by means of BSRP SGEH priority indicators. They include macrophytobenthos, macrozoobenthos, alien species, ichthyofauna, avifauna, mammals and a portion of the territory covered by the protected areas. The most prominent biodiversity changes were observed in the upper freshwater Neva Bay, and moderate changes, in the lower brackish part of the estuary. Eutrophication, alien species and dredging activities are the major threats to biodiversity of the estuary. At present, alien species contribute about 8 per cent of species richness, however, 60-90 per cent of the biomass of bottom animals. Filamentous algae blooms affect biodiversity of zoobenthos in the shallow coastal zone. The climate-mediated fluctuations in near-bottom oxygen conditions are responsible for deterioration of zoobenthos in the open waters of the estuary. The decline of the benthic aboriginal crustaceans led to impairment of food conditions for fish and to a sharp reduction of their populations, which, in turn, was partly responsible for the population decline of ringed seals. Milder winters have also contributed to the decline in the numbers of this species. Dredging activities related to construction of new lands and ports are the main factor affecting fish, submerged macrophytes and waterfowl in Neva Bay. A considerable part of fish spawning grounds and waterfowl habitats in Neva Bay has been lost during the last decades. The long-term measures for conservation and improving of biodiversity should take into account periodicity of climatic changes and planned development of the region.

New species and new records of rare ctenostome bryozoans of the genus Alcyonidium in the Russian Arctic Seas

New species of ctenostome bryozoan Alcyonidium pseudodisciforme sp. nov. is described. Subspecies Alcyonidium gelatinosum pachydermatum Denisenko, 1996 is raised to a species range and redescribed as A. pachidermatum Denisenko, 1996. New records of A. radicellatum Kluge, 1946 and A. proboscideum Kluge, 1962 are added to the list of bryozoan fauna of the Russian Arctic sector.

To the fauna of free-living freshwater nematodes of South-East Asia

The article provides data on freeliving freshwater nematodes, recently collected in Singapore, Thailand, Malaysia and Taiwan. Brief descriptions of most notable species are given. Diagnoses of the genus Mactinolaimus and species Ironus gagarini Tsalolikhin, 1987 are emendated.

A review of the genus Paranisitra Chopard (Orthoptera: Gryllidae: Eneopterinae)

The genus Paranisitra is redescribed. Its species are reviewed. Two new species of the genus are described from the Philippines (P. maculata sp. nov.) and the eastern part of Indonesia (P. diluta sp. nov.).

A new species of the genus Plectoptera Saussure and redescription of Eushelfordia pica Walker (Dictyoptera: Blattellidae) from Peru

A new species of the genus Plectoptera, P. vladimiri sp. nov. is described from Peru. The male of the type species of the genus Eushelfordia, E. pica, is redescribed and the male genitalia are examined for the first time. The taxonomic position of the genus Eushelfordia is discussed.

Keyword's index and author's index

Keyword's index and author's index.

Volume 313 (3), 2009

Date of publication — September 25, 2009



Cercomeromorph hypothesis and modern state in phylogenety of parasitic flatworms for a 100 anniversary of the Academician B.E. Bychowsky)

The alteration of approaches, methods and hypotheses in phylogeny of Platyhelminthes, mainly Neodermata, has been considered. It has been shown that the principal conflict in modern flatworm phylogeny is monophyly of Neodermata, supported by both molecular and comparative morphological data, which collides with current viewpoint on the origin and evolution of Trematoda.

Ecological features of permanent ectoparasites

There are more than 9000 species of permanent ectoparasites of terrestrial vertebrates among insects and acarines. Permanent ectoparasites spend entire life time or only part of their life cycle on and inside the skin, hairs and feathers of their hosts. Such ectoparasites feed on blood, lymph, products of dermal glands and particles of skin, hairs and feathers. Permanent ectoparasites can be characterized by the following features: often consumption of small amounts of food, small to moderate fecundity, short period of development of one generation, short life span and incapability to starvation for a long period of time. They infest new host individuals through the direct contact between hosts or by the phoretic way.

On causes and mechanisms of appearance of mini polymerous Hymenolepididae (Cyclophyllidea, Cestoda), parasites of shrews

The direction of the morphological transformations in the phylogenesis of Hymenolepididae from shrews depends on the nature of dissemination of hexacanths in the external environment. The organization of strobila and proglottids in Neoskrjabinolepis Spassky, 1948 and Lineolepis Spassky, 1958 which have hexacanths going out into the external environment inside the segment-oophor is determined by the group dissemination of hexacanths. At the group dissemination of hexacanths the probability of infection for intermediate hosts depends on their number in the external environment rather than on the fertility of individual proglottids. The nonselective group elimination of free-living larvaе in the external environment results in a higher rate of strobilation, number of proglottids in the strobila and low fertility of proglottids in Neoskrjabinolepis and Lineolepis. However the polymerous strobila of Neoskrjabinolepis and Lineolepis is formed under the obligate high density of infrapopulations in the intestine of small-sized hosts. In turn the selection for miniaturization of the polymerous strobila predetermines heterochronic reorganizations of these cestodes. The acceleration of morphogenesis of the genitals is the evolutionary mechanism of juvenilization of mature proglottids of Neoskrjabinolepis and Lineolepis which leads to a significant decrease in their size and change in their form. The heterochronic reorganizations in the genitals of the strobila are in turn accompanied by coordinated changes in the form and size of gonads in mature proglottids. A considerable fall in fertility (the number of hexacanths) of proglottids in Neoskrjabinolepis and Lineolepis is caused by these changes too.

Ways of the parasitism origin in the phytonematode orders Tylenchida and Aphelenchida

The following principal features of the plant parasitic nematode evolution are listed and illustrated. Phytonematodes have been originated from saprotrophic nematodes (bacterio- and mycotrophic ones), firstly plant hosts and later insect vectors were consequently included in their life cycle. The speciation factors were changing depending on the stage of evolution of the host–parasite relationships. In the primitive plant parasitic nematode taxa the species divergence is associated with the soil-climatic conditions; in the most advanced taxa of the sedentary phytonema todes the co-evolution with their plant host taxa took place; in the nematode taxa associated with insect vectors the insect families served as the speciation factors for nematodes. At the key steps of the host-parasite relations evolution, similar adaptations appeared independently in different phylogenetic lines. In transition to endoparasitic feeding, the stylet enforced and the lobe of the enlarged pharyngeal glands was formed. As the adaptations to the migratory endoparasitism in plant tissues, posterior part of the female body shortened and the posterior genital system branch located there, reduced in the postembryogenesis. In the sedentary endoparasitic nematodes the topic and trophic relations with plant hosts were developing independently (incoherently) in different phylogenetic lines. But all sedentary phytonematodes have common features: the specialized infective juvenile stages were differentiated in the life cycle; the diameter of adult female body, occupied with a hypertrophied genital system with mature eggs containing infective juveniles, has been increased significantly. In insect-vectored nematode taxa the special dispersal entomophilic stages were differentiated in the life cycles by two different phylogenetic lines: in one line the transmission juvenile stages (dauerlarvae) were formed, in the second line – the inseminated but not egg-producing transmission females were arisen. The parallelisms in development of similar adaptations indicate the general principles and tendencies of the plant parasitic nematode evolution.

Systematics, geographic distribution and evolutionary pathways of fleas

The geographic distribution and host-parasite relations of fleas and their hosts, mammals and birds, were analyzed by means of the analytic system PARHOST1. The parasite-host relations were considered using various recent phylogenetic hypotheses for fleas. The formerly proposed taxonomic and phylogenetic systems of the order Siphonaptera based on the molecular data from 4 loci (Whiting et al. 2008) is critically analyzed. The results based on that molecular study once more showed problems in the constructing of the classifications of fleas, and conclusions drawn out from these results are rather provisional. In general, fleas are characterized by the nest-and barrow type of parasitism, in which the distribution of species is determined by adaptations both to the warm-blooded host and to microbiotopic conditions in the nest. These characteristic properties of flea’s ecology determined a complicate pattern of host associations between particular flea taxa with host taxa. The majority of higher taxa of the order Siphonaptera are characterized by a wide range of host taxa. The diversity of features in fleas derived from the common morphological basis that significantly embarrasses the recognition of peculiar features caused by the coevolution of flea and host (mammalians and birds).

Transposable elements as a potential vectors for horizontal gene transfer in host-parasite system

Horizontal gene transfer is one of the principle ways that maintain the genetic diversity in prokaryotes. However the genetic transfer between eukaryotes is assumptive. In light of this hypothesis DNA transposable elements are the likely candidates for the eukaryotic horizontally transmitted genetic elements. The directed horizontal transfer may only occur in the case of physical contact of organisms involved in this process. This sort of interaction takes place in host–parasite systems. Nowadays the hypothesis of horizontal gene transfer is based on the sequence similarity, sporadic distribution and conjectural ways of transposons transduction. However, all highly homologous elements found are inactive due to mutations within their ORFs. The percent of identity does not represent the origin of transposable element and therefore cannot testify to its transduction. Most of the transposable elements are inactive. Nevertheless the active copies may function as active mutators giving rise to genetic diversity under the ecological stress. In spite of the absence of direct proofs of horizontal gene transfer there are indirect data indicating that this process might occur many times in the course of eukaryotic evolution.

Generation of the reactive oxygen species during immune reactions of arthropods

Topics considered in this review include generation of reactive oxygen species (ROS), their features and sources in arthropods and the role of ROS in development of immune response against parasites. The cellular and humoral immune reactions of hosts are enhanced under parasite penetration. The main cellular defense refers to hemocytemediated immune responses like phagocytosis of small particles as well as isolation and destroying large particles by encapsulation. These processes are accompanied by melanin formation as results of phenoloxidase activity and melanogenesis. In this review the melanogenesis is examined as one of the reasons of increased generation of ROS which have a high reaction activity and ability to destroy parasites.

Strategies of search behaviuor in trematode Cercariae

On the base of analysis of original and literature data four basic strategies were distinguished in host-search behaviour of trematode cercariae. There are active search (1), passive waiting (2), active waiting (3) and prey mimetism (4). Many of the Xiphidiocercaria, cercariae of some Echinostomatidae, Psilostomatidae, Acanthocolpidae and Lepocreadiidae as well as cercariae of Fasciolidae, Haploporidae, Notocotylidae, Pronocephalidae, Gladorchiidae and some Haplosplanchnidae encysting on surface of underwater substrates follow the first strategy. These cercariae demonstrate a continuous swimming and photo-, geo- and sometimes chemoreactivity. The second strategy is characteristic for cercariae of Microcerca group with ambuscade behaviour. These cercariae exhibit pronounced oscilloreactions whereas other orienting reactions are feebly marked or even absent. Cercariae of Bucephalidae and Hemiuroidea which float passively in the water column also follow the strategy of passive waiting. The strategy of active waiting is characteristic of cercariae (Furcocercaria, Pleurolophocerca, Parapleurolophocerca, etc.) with an intermittent type of locomotion, where periods of active movement alternate regularly with periods of repose. These cercariae demonstrate a wide range of orienting reactions. The pray mimetism strategy exhibit cercariae of some trematodes (Azygiidae, Bivesiculidae, some Echinostomatidae, Heterophyidae, Lepocreadiidae, Gyliauchinidae, etc.) infecting their hosts passively per os. The active searching cercariae (strategy 1) usually infect sedentary animals or mobile ones but during periods of their minimal locomotory activity. The cercariae exploiting strategies 2–4 predominantly infect mobile animals. It was emphasized that the model of foraging strategies produced by Schoener (1971) and Huey and Pianka (1981) for free-living animals could be applied to analysis of cercarial hostsearch behaviour.

Patterns in the dynamics and distribution of parasite abundance in small mammals

Abundance distribution patterns of the cestode Ditestolepis diaphana (Colodkowsky, 1906) in the common shrew Sorex araneus L., 1758 and the nematode Heligmosomum mixtum (Schulz, 1952) in the bank vole Myodes glareolus (Schreber 1780) populations were investigated. We prove that in most cases parasite abundances are modeled by negative binomial distribution (NBD). The patterns revealed for the parasite species studied evidence relations in the host–parasite system to be quite steady. An attempt was made to interpret NBD parameters describing variations of mean abundance and variance of the parasite abundances, which are apparently due to differences in host susceptibility.

Parasitic system reflects population structure of a parasite: conception and terms

Population and community consequences of host–parasite interactions are considered. The special attention is given to the various aspects of population level of host-parasite interactions and to approaches to analysis of structure of parasitic systems (systems of populations of the various hosts united in community by interaction with population of a parasite). In the structure of parasitic systems it is allocated two essential architectonic components. The first is a consequence of the differentiated life cycle of a parasite and subdivision of its population onto phase groups (a metastructure of a parasitic system). The second is a consequence of environmental subdivision of parasites (parastructure of a parasitic system). As a whole the parasitic system is considered as a system of para- and metaelements. Importance of population and community levels consideration of the host-parasite interactions is underlined. The special attention is given to working out of a convenient and consistent terms framework for these purposes. The approach developed in the work can be considered as a methodological basis for the analysis of the hierarchical systems formed on the basis of any other type of mutual relations of organisms (others, than interaction of a host– parasite).

On structural interfacing of trophic and parasite relations of nektonic squid Sthenoteuthis pteropus in the tropical atlantic: coevolutionary aspect

The paper describes the trophic and parasitic relations interfacing of mass abundant orangeback squid Sthenoteuthis pteropus (OS) in the open waters of the Tropical Atlantic. There are described the data on squid’s food, predator and helminth species compositions and theirs ontogenetic, sex and infraspecific variability, and on the place and role of distinct stages of OS life cycle in the trophic and parasite structures of oceanic communities. The predator-prey size relations are 8–20% absolute squid length. Due to this fact the shifts of the main food groups are taken place in squid ontogenesis and, accordingly, there are changes in helminthes species composition and infection rates. The place and role of squids of different ontogenetic stages in the helminths life cycles is also different. These helminthes are transmitted by oceanic trophic webs. Thereupon there are demonstrated the existence of important differences between various life cycle stages, sexes and infraspecific groups of OS in oceanic tropho-parasitic structure. The working hypothesis on mechanism of coevolution of nektonic squids and their helminthes is formulated on the base of «using» by helminthes a quasi-stable trophic web of the vast oceanic pelagic zone.

Spiny-headed worms (Acanthocephala) in the basin of the Sea of Okhotsk: taxonomic and ecological diversity

For the first time the inventory of the taxonomic composition of the spiny-headed worms has been carried out in the basin of the Sea of Okhotsk. It has revealed their high biodiversity. We have registered 100 species and forms of 28 genera of 17 families of 8 orders of 3 classes in composition of the phylum Acanthocephales. Spiny-headed worms of hydrotopic species, both sea and freshwater, totally dominate in the basin of the Sea of Okhotsk. Parasitic systems of the background species of the sea spiny-headed worms are basically composed by the dominant species of intertidal and near-shore sea amphipods, and besides of decapods as intermediate hosts. Structure and biotopic belonging of parasitic systems of the freshwater spiny-headed worms species in the region are determined by the freshwater crustaceans belonging to ostracods of genera Cypria and Candona, amphipods of the genus Gammarus and isopods, namely water slaters of the genus Asellus. Broad transmission of the spiny-headed worms within certain ecosystems and over the basin of the Sea of Okhotsk is realized by their definite and parathenic hosts. Short- and long-distance migrant fishes, birds and mammals are most important among them.

Volume 313 (2), 2009

Date of publication — June 25, 2009

Phylogeny of feather mites of the subfamily Pterodectinae (Acariformes: Proctophyllodidae) and their host associations with passerines (Passeriformes)

A phylogenetic hypothesis of the feather mite subfamily Pterodectinae Park et Atyeo, 1971 (Astigmata: Proctophyllodidae), currently including 165 species in 19 genera, was constructed by means of the maximum parsimony approach. It is shown that the proctophyllodid mites characterized by the epigynum fused to epimerites in females and by the absence of terminal membranous extensions of the opisthosoma in males that were arranged by previous authors into two subfamilies, Pterodectinae and Rhamphocaulinae, constitute a common phylogenetic branch within Proctophyllodidae. It is proposed to threat this whole branch as the subfamily Pterodectinae. The subfamily Pterodectinae in the new sense consists of two branches, which are treated as the tribes Pterodectini trib. nov. and Rhamphocaulini Park et Atyeo, 1971 stat. nov. The generic contents of these tribes are rearranged comparing to those in Pterodectinae and Rhamphocaulinae of previous authors. A preliminary hypothesis about the origin and dispersion of Pterodectinae on passerine hosts is proposed. It is suggested that this subfamily originated on the ancestors of Passeriformes. The origin and subsequent diversification of two major phylogenetic branches (Pterodectini and Rhamphocaulini) was related with two main taxonomic grouping of avian hosts, passerines and hummingbirds (Apodiformes: Trochilidae), respectively; although on the latter hosts they are of secondary origin. The phylogeny, host associations and geographic distribution of pterodectines predominately associated with passerines generally correspond to the phylogeny and historical biogeography of the order Passeriformes. The current distribution of pterodectines among passerines was realized by cospeciation with their hosts, and also by numerous cases of switching to new host taxa, mainly within Passeriformes, but also to bird of other orders. Nanopterodectes nom. nov. is proposed for the pterodectine genus Nanodectes Mironov in Mironov et al. 2008b (Acariformes: Proctophyllodidae), which was preoccupied (Rentz 1985; Orthoptera: Tettigoniidae); the sole species of this genus gets a new name Nanopterodectes formicivorae (Mironov, 2008) comb. nov.

Craniometrical variability in insular populations of brown bear (Ursus arctos, Carnivora) from Hokkaido, Sakhalin and South Kurils

The morphometrical analysis of 84 skulls of adult males of Ursus arctos from islands of the southern part of the Okhotsk Sea has revealed differences between brown bears from Hokkaido and South Kurils (U. a. yesoensis) and bears from Sakhalin, Shantar Islands and adjacent part of Asia (U. a. beringianus). The analysis has revealed craniometrical features of bears from three genetically different groups from Hokkaido and has shown similarity of bears from South Kurils (Iturup I., Kunashir I.) with bears of the eastern genetic group (B) from Hokkaido. The differentiation of bears into groups is mainly caused by the variation of width of the cerebral part and the basis of the skull and of the jaw height. Bears from Sakhalin are close to the continental ones, but have the smaller sizes and narrower skull in the postorbital area. The morphometrical data do not correlate with the supposed time of immigration of different groups of the brown bear to Hokkaido. Most likely, these data are defined by local adaptations of the studied populations. In our work, quantitative (informational) characteristics of the morphological (morphometrical) diversity of skulls of bears of different subspecies, important for comparative studies, are defined for the first time. Skull of U. a. yesoensis is characterized by a low variety in comparison with those of U. a. beringianus and other subspecies. The hypothesis about rather high morphological specialization of U. a. yesoensis, U. a. beringianus and U. a. piscator in comparison with U. a. arctos and U. a. collaris is formulated.

The co-occurence of non-lissamphibian temnospondyls and salamanders in the late Jurassic of the southern Junggar Basin (Xinjiang Autonomous Region, NW China)

So far, the Jurassic co-occurrence of non-lissamphibian temnospondyls and early temnospondyl lissamphibians was known only for the Middle Jurassic Balabansai Svita in the Fergana Depression, Kyrgyzstan and the Peski Quarry near Moscow, Russia. Here we report the co-occurrence of non-lissamphibian temnospondyls and lissamphibians (salamanders) from the Late Jurassic (Oxfordian) Qigu Formation of the Liuhuanggou locality in the southern Junggar Basin, China. This represents a considerable temporal and geographical range extension for the nonlissamphibian temnospondyl-early lissamphibian faunal association.

On the position of the genus Zizyphia Chretien, 1908 in the system of Gelechioidea (Lepidoptera)

The genus Zizyphia hitherto considered in the family Gelechiidae (Lepidoptera) is placed into the family Depressariidae (tribe Orophiini). This conclusion is substantiated by the peculiarities of the shape and venation of the wings, and the structure of the male genitalia studied in this genus for the first time.

Stegosaur remains from the Middle Jurassic of West Siberia

The Middle Jurassic (Bathonian) Itat Formation at Berezovsk Quarry, Krasnoyarsk Territory (West Siberia, Russia) has produced abundant remains of stegosaurs. Numerous isolated teeth are found at various microvertebrate sites, and associated skeletal remains, mostly vertebrae, ribs, and ilio-sacral block fragments were excavated at the Stegosaur Quarry. These remains likely belong to one taxon which is characterized by numerous secondary ridges on one crown side in cheek dentition, six vertebrae in the synsacrum, four sacral and one dorsosacral ribs, lack of dorsal process on the transverse process in anterior caudals, moderately expanded tops of the neural spines in anterior caudals, and large triangular transversely thin dorsal dermal plates. The combination of these and other features is not characteristic for any other known stegosaur taxon and the Berezovsk stegosaur likely represents a new taxon. Among known stegosaurs it is most similar with Stegosaurus from the Late Jurassic and Early Cretaceous of North America and Asia by having numerous secondary ridges on teeth, a right angle between the supraacetabular flange and the anterior iliac process of ilium and in the structure of the dorsal dermal plates. It differs from Stegosaurus by plesiomorphically unexpanded tops of the neural spines and lack of dorsal process on the transverse processes in the anterior caudal vertebrae. The Berezovsk stegosaur is among the oldest stegosaurs in the fossil record.

Postembryonic development of the copulative apparatus in representatives of three genera of the family Planorbidae (Gastropoda: Pulmonata)

Development of the copulative apparatus in the course of postembryogenesis in representatives of the three genera of the family Planorbidae: Anisus vortex, Gyraulus albus, and Choanomphalus amauronius was studied based on the laboratory reared molluscs and on the collection material for the first time. Morphological description of the stylets examined with SEM is given. Problems of the stylet formation in the studied species and genera are considered. The importance of the stylet organization for the planorbid taxonomy is discussed.

Anatomy and ultrastructure of mitgut in the water mite Piona carnea (Koch, 1836) (Acariformes: Hydrachnidia)

Midgut of adult mites Piona carnea (Koch, 1836) was investigated in transmission electron microscope and on semi-thin sections. The midgut ends blindly and is composed of the middle portion (ventriculus) and two paired diverticula running forward and backward as well as of the middle unpaired diverticulum located in the frontal body region. The midgut epithelium is formed of one type of digestive cells throughout the ventriculus and diverticula being, however, in different physiological conditions and located freely in the midgut epithelium. The cells in different physiological conditions may be conventionally characterized as (1) the reserve cells, (2) the cells rich in nutrition vacuoles and (3) the excretory cells. The reserve cells are flat cells forming the midgut wall. They are inactive with respect to the digestive processes. The cells rich in nutrition vacuoles are strongly hypertrophic and contain numerous nutrition vacuoles, reserve nutritive such as glycogen and lipids as well as spherites. The apical cell zone shows intensive endocytotic processes. Digestion is realized by the intracellular type. The excretory cells are the cells, which have already completed the intracellular digestion. They are characterized by the very thin cytoplasmic layer applied to the cell membrane, whereas the remaining cytoplasm is filled with the extremely large clear vacuoles. These cells are mostly devoid of organelles.

To systematics of the genus Stegopterna Enderlein, 1930 (Diptera: Simulidae)

The collection of blackflies (Diptera: Simuliidae) of the Zoological Institute of the Russian Academy of Sciences is revised. Redescriptions of 11 species of the genus Stegopterna Enderlein, known from the territory of the former USSR are given. A new species, S. tundrensis sp. nov. is described. Key to all 18 species of the genus is provided.

Volume 313 (1), 2009

Date of publication — March 25, 2009

New species of red-backed vole (Mammalia: Rodentia: Cricetidae) in fauna of Russia: molecular and morphological evidences

The new species for the fauna of Russia, Hokkaido red-backed vole (Myodes rex), has been identified at the south of Sakhalin Island (Dolinsk District). Its identification was reliably confirmed by molecular and morphological methods. Undoubtedly, this species is much more widespread in islands of the Far East. Some records of M. sikotanensis from Sakhalin including the so-called “microtinus” form, actually, should be reidentified as M. rex. The voles with complex molars from Shikotan Island and probably those from Zelenyi (= Sibotsu) Island also belong to M. rex.

Effect of low-level industrial heating on seasonal cycle transformation in cladocerans

We studied effects of a low-level industrial heating caused by heating-electric power station on changes in seasonal adaptations in cladocerans inhabiting the Kama River Reservoir (the Volga River tributary). The biological significance of low-level industrial heating was analyzed by comparison of two stations: one with natural temperatures and another one affected by cooling water from the Kama Heating-Electric Power Station. We found that even relatively low (less than 2°C) difference in seasonal temperature between these two stations resulted in changes of reproductive mode in the most abundant species of Cladocera (Bosmina longirostris (Muller, 1785), Daphnia longispina Muller, 1785, and Diaphanosoma brachyurum sensu lato). At station with low heating, all species of cladocerans had some negative changes in their seasonal life cycles (sex proportion, resting egg production etc) with following disturbances in their over-wintering adaptations. Our results on early appearance and increasing of male proportion in population structure caused by industrial heating can be used for assessment of negative consequences of low-level industrial heating and global climate changes. With help of modeling, these data can be used for creation a new methods of prognosis both in global and local scales. It was finally resumed that low-level industrial heating, similar in scale to those observed during last decades under climate changes, leads to significant declining in population density and productivity in dominant species of cladocerans.

Crickets of the family Mogoplistidae (Orthoptera) from Ascension and Saint Helena islands, Atlantic Ocean

Six species of Mogoplistidae were found in Ascension and Saint Helena islands. All of them are members of the tribe Arachnocephalini. Five of them are new and belonging to a new genus (Discophallus, gen. nov.: D. ascension, sp. nov., D. philipi, sp. nov., D. myrtleae, sp. nov., D. pallidus, sp. nov., D. amplus, sp. nov.). Three of them are from Ascension I. and two, from Boatswainbird I. (a small island situated near the previous one); one species, Cycloptiloides canariensis (Bol.), is presented in Ascension and St. Helena islands. Descriptions of new taxa and a key for species determination are given.

A new genus and species of sap beetles from Bolivia (Coleoptera: Nitidulidae)

The paper deals with description of Bolivitoxus diffusopunctatus, gen. et sp. n. from Bolivia, which belongs to the Pocadius-complex of genera of the tribe Nitidulini (Nitidulidae). Taxon Pseudothalycra Howden, 1962 is considered as a subgenus of the genus Thalycra Erichson, 1843, stat. nov. New conception of the Pocadiuscomplex of genera involving also former Thalycra-complex is proposed.

New species from the order Cyclostomata (Bryozoa) from the northern and middle Kurile Islands

Six new species of cyclostome bryozoans are reported from the shelf of the northern and middle Kurile Islands. These include one new genus Paulina (type species P. taylori, sp. nov.), which is distinguished from Stomatopora Milne-Edwards, 1838 in having a basal gonozooid with a suborbicular shape, ultrastructure of frontal exterior wall with longitudinal stripes of calcification and unique ultrastructural fabric of coarse chevrons. The other five species are represented by Crisiella chirpoiensis, sp. nov., Desmatelesia repens, sp. nov., Desmeplagioecia pastiliformis, sp. nov., Heteropora urupae, sp. nov., and Tubulipora duplicatocrenata, sp. nov.

Mammoth (Mammuthus primigenius) from the Late Pleistocene of Chuvashiya, European Russia

The paper presents a description of a partial skeleton of the woolly mammoth (Mammuthus primigenius) found in 2001 at the Khoma River locality in Chuvashiya, European Russia. This skeleton demonstrates replacement of m2 by m3 in the lower jaw and epiphyses of most bones not fused. Based on morphological data, the skeleton belongs to adult individual died at the age of 28–35 years, probably, a male. The age of the mammoth from Khoma River is estimated at 33640 ± 270 by AMS-radiocarbon dating, which corresponds to the Middle of Valdai interglacial.

Organization of stylets of mollusсs of the genera Gyraulus and Choanomphalus (Pulmonata: Planorbidae)

Morphological characters of stylets of mollusks (Pulmonata: Planorbidae) of two widely distributed species of the genus Gyraulus (G. аlbus, G. borealis) and two species of the genus Choanomphalus (Ch. amauronius, Ch. rossmaessleri) have been studied by Scanning Electron Microscope (SEM) in details and are described herein. The importance of the stylet morphology for the taxonomic descriptions is discussed.

New material and a revision of turtles of the genus Adocus (Adocidae) from the Late Cretaceous of Middle Asia and Kazakhstan

This paper reviews shell material of the turtle genus Adocus (Adocidae) from the Late Cretaceous of Middle Asia and Kazakhstan. Three previously recognized species of Adocus from this area are described in detail based on published and new material. The previously recognized species are A. aksary (Dzharakuduk, Uzbekistan; late Turonian), A. foveatus (Kansai, Tajikistan; early Santonian), and A. kizylkumensis (Khodzhakul, Khodzhakulsay and Sheikhdzheili, Uzbekistan; early Cenomanian). Material of additional forms of Adocus are described, two of these are named as new species: Adocus dzhurtasensis, sp. nov. (Dzhurtas, Kazakhstan; Santonian – early Campanian), Adocus bostobensis, sp. nov. (Akkurgan, Baybishe, Buroinak, and Shakh-Shakh, Kazakhstan; Santonian – early Campanian), and Adocus sp. indet. (Itemir, Uzbekistan; Cenomanian).



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Last modified: February 5, 2019