The eyespots of the oncomiracidium of Euzetrema knoepffleri (Monogenea): ultrastructure and evolution during the life-cycle (author's transl)]

Euzetrema knoepffleri (Monogenea, Monopisthocotylea) is a parasite of the urinary bladder of Euproctus montanus (Amphibia, Urodela). The eyespots of the oncomiracidium of E. knoepffleri are rhabdomeric; each anterior pigmented cell has one rhabdomere, each posterior pigmented cell has two rhabdomeres. This pattern is quite similar to that of the eyespot of another Monopisthocotylea, Entobdella soleae but the lack of cristalline lens in E. knoepffleri appears as a new feature of the Monopisthocotylea. The symmetry of the pigmented structures seems to be effectively connected with the swimming mode of the larva. Moreover, the ultrastructural differences between the two species Euzetrema knoepffleri and Entobdella soleae may be in relation with their different behaviour concerning light. After the fixation of the larva on its host, the comparative study of the evolution of the eyespots, shows the disappearance of the cristalline lens in Entobdella, and the loss of rhabdomeric structures in Euzetrema. These differences seem related with the nature of the microbiotope of the adult: Entobdella soleae is a skin parasite, Euzetrema knoepffleri a reno-vesical one.     

A DISEASE OF SCABIOSA CAUCASICA CAUSED BY THE NEMATODE APHELENCHOIDES BLASTOPHTHORUS N.SP.

Scabiosa caucasica has been found affected by a new species of Aphelenchoides , herein described and named A. blastophthorus. The symptoms of disease are destruction of the inflorescences and distortion of the leaves with reduction of the laminae. Similar symptoms were produced in scabious by experimental infestation. The nematode can infest teazle ( Dipsacus fullonum ), but has not been found naturally occurring on any host but scabious.     

Paranoplocephala maseri n. sp. (Cestoda,Anoplocephalidae), a parasite of sagebrush voles Lemmiscus curtatus (Rodentia) in the USA

Paranoplocephala maseri n. sp. is described from Lemmiscus curtatus (Cope) in the USA. The new species is related to Paranoplocephala omphalodes (Hermann, 1783), P. caucasica (Kirschenblat, 1938), P. kirbyi Voge 1948, P. microti (Hansen, 1947) and P. macrocephala (Douthitt, 1915) sensu Genov et al. (1996). P. maseri n. sp. differs from P. omphalodes in the position of the genital pores, testes and cirrus-sac; from P. caucasica, in which there is an unarmed cirrus, in both the distribution and larger number of testes; from P. kirbyi in the distribution of the testes, the position of the genital pores and egg dimensions; from P. microti in the distribution and smaller number of testes, the smaller egg dimensions and the position of the genital pores; and from P. macrocephala in the position of genital pores and cirrus-sac.     

A fine line between sex and unisexuality: the phylogenetic constraints on parthenogenesis in lacertid lizards

A phylogeny of Caucasian rock lizards (genus Darevskia , formerly Lacerta ) was reconstructed using mitochondrial DNA sequence and allozyme data. All 15 bisexual species grouped into three major clades: the caucasica, saxicola and rudis clades. Unisexual Darevskia originate from inter-clade hybridization, never from within clades. Only two clades, the caucasica clade and the rudis clade, were involved in forming unisexuals; the saxicola clade was never involved. Furthermore, the hybridization is directional in that the caucasica clade contributed only maternal parents and the rudis clade only paternal parents. The formation of unisexual species is best explained by sexually directional phylogenetic constraints. We hypothesize that the causative agents are likely to be genes linked with the sex chromosomes within the parental sexual species.     

An electrophoretic study of the systematic relationships of some closely related goby species (Pisces, Gobiidae)

An electrophoretic study of genetic variation at 31 loci in each of nine closely related gobiid species was carried out in order to assess their systematic relationships. The species used were: Pomatoschistus canestrinii, P. lozanoi, P. marmoratus, P. microps, P. minutus, P. norvegkus, P. pictus, Knipowitschia caucasica, Neogobius melanostomus. Genetic distances ( D ) and identities ( I ) were calculated by Nei's method for all 36 pairwise comparisons and dendrograms were constructed.
The results show that the very similar and cross-fertile species pair, P. lozanoi and P. minutus , have the highest I value; P. norvegkus has high I values with both species. Pomatoschistus marmoratus and P. microps also display high genetic similarity with each other. The remaining Pomatoschistus species and Knipowitschia caucasica are broadly and moderately equidistant from each other and from the five species refferred to above, while Neogobius melanostomus is considerably more distant from all other species.
These findings essentially agree with the pattern of relationships established using classical taxonomic approaches. However, the observation that Knipowitschia caucasica is as similar to Pomatoschistus spp. as the latter are to each other suggests that the generic distinction of Knipowitschia could usefully be reconsidered.     

小麦族披碱草属、鹅观草属和猬草属模式种的C带研究

采用改良的Giemsa C带技术,分析了小麦族披碱草属、鹅观草属和猬草属模式种的染色体C带带型。Elymus sibiricus、Roegneria caucasica和Hysrix patula的染色体在Giemsa C带带型上存在明显的差异,显示了这3个属模式种的物种特异性。3个模式种的Giemsa C带核型表明,C带带纹主要分布在染色体的末端和着丝粒附近,而中间带相对较少。对E.sibiricus、R.caucasica和H.patula的St、H、Y染色体组C带带型与其它物种的St、H、Y染色体组C带带型的差异进行了讨论。     

Molecular mechanisms of adaptation to hyperthermia in higher organisms. III. Induction of heat-shock proteins in two Leishmania species

The heat-shock proteins (hsp) induction in two species of Leishmania have been investigated. The species studied are parasites of two species of lizards (Lymnodactylus caspins and Agama caucasica) differing by temperature of correspondent ecological niche. Our results show that Leishmania species restricted to high-temperature host (Agama) is capable to synthesize its proteins at extreme temperatures (38, 40 degrees C) with greater intensity. Moreover, the species of Leishmania studied differed by heat-shock proteins pattern, the intensive synthesis of hsp88 and hsp48 being the characteristic features of Leishmania species, restricted to the high-temperature host.     

利用RAPD分析披碱草属、鹅观草属和猬草属模式种的亲缘关系

利用随机扩增多态性DNA（RAPD）技术对小麦族披碱草属、鹅观草属和猬草属3个属的模式种进行了基因组DNA多态性分析。42个引物产物的290条谱带中,257条（88.62%)表现出多态性,说明披碱草属、鹅观草属和猬草属3个属的模式种间具有丰富的遗传多样性。利用290个RAPD标记,计算材料间Nei氏遗传相似性系和遗传距离,在NTSYS程序中利用UPGMA进行聚类。结果表明,Elymus sibiricus种不同居群间的遗传差异较小,遗传距离在0.097-0.180之间。E.sibiricus,Roegneria caucasica和Hystrix patula的种间遗传差异明显,遗传距离在0.458-0.605之间。H.patula与E.sibiricus的亲缘关系较近。R.caucasica与E.sibiricus的亲缘关系较远。     

Phylogenetic reconstructions in the genus Capra (Bovidae, Artiodactyla) based on the mitochondrial DNA analysis

Mitochondrial genome fragments were examined in all species of the genus Capra (Bovidae, Artiodactyla). Phylogenetic analysis was carried out using 59 cytochrome b gene sequences (392 bp), and 22 sequences of the mtDNA variable fragment (402 bp). In the control region, two unique deletions were revealed. One of the deletions was found only in Capra cilindricornis (17 bp), while another one grouped C. caucasica with C. aegagrus (1 bp). The group of Caucasian wild goats splits into two clades, and furthermore, the sequences of C. caucasica demonstrate remarkable similarity to the sequences of C. aegagrus, while C. cylindricus seems to have evolved independently for a long period of time. It was demonstrated that C. pyrenaica and C. ibex were extremely close to one another. Capra sibirica formed an outer group relative to the other species, and according to our data, was the most ancient species of the genus. On the contrary, genetic distance separating C. falconeri (the most independent species of the genus related to its morphology) from the other species is small.     

Evaluation of the acarofauna of the domiciliary ecosystem in Juiz de Fora, State of Minas Gerais, Brazil.

From August 1999 to January 2000, samples of house dust were collected from 160 domiciles in the city of Juiz de Fora, State of Minas Gerais, Brazil. In 36 of these domiciles kitchen samples were obtained. Prevalence rate was 77.5%, varying according to the geographical sector. There were found 2,278 specimens of mites, with 1,530 (67.2%) in the adult stage and 748 (32.8%) in immature forms. The main species found were Dermatophagoides pteronyssinus, D. farinae, Euroglyphus maynei, Blomia tropicalis and Tyrophagus putrescentiae. In a minor incidence we found Lepidoglyphus destructor, Suidasia pontificiae, Chortoglyphus arcuatus, Cheyletus malaccensis, C. fortis, Ker bakeri, Cheletonella vespertilionis, C. caucasica and others. C. vespertilionis and C. caucasica were identified for the first time in the domiciliary ecosystem and in Brazil. The abundance rate and the infestation intensity were analyzed. There was a varied correlation between climatic conditions and positive domiciles and number of mites. The difference between the number of positive domiciles in the urban area and in the expanding urban area was significant and so was the difference between samples from the domiciles compared to those from the kitchens.     

Toward the phylogeny of Caucasian rock lizards: implications from mitochondrial DNA gene sequences (Reptilia: Lacertidae)

A maximum parsimony phylogeny of 14 Caucasian species of rock lizards, genus Ijicerta , subgenus Archaeolacerta , was constructed from mitochondrial cytochrome b and ATPase 6 partial gene sequences. Congruence analyses were carried out between the two genes. A synthesis of the data sets reveals three well supported monophyletic groups: (1) the caucasica group including ( Lacerta derjugini (( Lalpina, L. clarkorum ) ( L. caucasica, L. daghestanica ))); (2) the rudis group including ( L. parvula ( L. portschinskii ( L. vakntini, L. rudis ))); and (3) the saxicola group including ( L. mixta ( L. nairensis ( L. saxicola, L. raddeijj ). Despite the diagnosis of three groups, the placement of L. praticola as a basal taxon is uncertain, as are the relationships among the three groups. The mitochondrial DNA sequence data suggested prior hybridization between L. mixta and L. alpina and possibly between L. saxicola and L. nairensis. Lacerta raddei was resolved as a paraphyletic species on the mtDNA tree; this may result from either hybridization or random gene sorting.     

Comparative karyological study of lizards of family Agamidae. II. Karyotypes of 5 species of the genus Agama]

Chromosome complements of the following species were described: Agama sanguinolenta Pallas, 1813; A. caucasica Eichwald, 1813; A. erythrogastra Nikolsky, 1896; A. lehmanni Nikolsky, 1896; and A. hymalayana Steindachner, 1867. Agama sanguinolenta has 46 chromosomes, all of them being telocentric. The remaining 4 species show 2-n equal to 36:6 pairs of meta- or submetacentric macrochromosomes and 24 microchromosomes. Sex chromosomes have not been found. Possilbe evolutionary interpretation of a profound karyologic divergence in the genus Agama and karyotypic relationships of Agamidae with Iguanidae of the New World, are discussed.     

The ability of flea species on the common vole from mountainous Dagestan to transmit and preserve the causative agent of plague

The infection ability and terms of preservation of plague microbe in fleas of common vole from Dagestan high-mountain plague focus (Frontopsylla causasica, Megabothris turbidus, Ctenophthalmus intermedius and Amphipsylla rossica) was studied experimentally. Block formation and transmission of the infection by F. caucasica and M. turbidus was observed. The transmission of plague microbe by Ct. intermedius fleas was first carried out. These species of fleas preserve the infection for a long time. Experiments with fleas of A. rossica yielded negative results.     

Reproductive strategies and early development of three freshwater gobies

Three species of gobiid fish inhabit the freshwater Lake Trichonis of western Greece. Two of these species, Economidichthys pygmaeus and E. trichonis are endemic, and the third is the widespread Knipowitschia caucasica . There are habitat separations between the three species, E. pygmaeus and E. trichonis prefer vegetated areas, the first being fully demersal at all stages of development and the second being semi-demersal. Knipowitschia caucasica prefers sandy bottoms and is distributed in shallower waters. Female E. pygmaeus and E. trichonis spawn in nests prepared by the males in the cavities of broken reeds. The males subsequently guard the eggs until they hatch, with females playing no role in parental care. Economidichthys trichonis is probably the smallest freshwater European species. Its eggs are ovoid, measuring about 0.64 × 0.58 mm, from which tiny, unpigmented and incompletely developed pelagic larvae hatch out after an incubation period lasting less than 1 day at a water temperature of 19.5° C. The eggs of E. pygmaeus are cylindrical and larger, measuring about 2.38 × 0.89 mm, from which relatively large, strongly pigmented and ontogenetically more advanced larvae hatch out after a longer incubation period. Both species reproduce only once in their lifetime, at the age of 1 year, and die shortly after spawning, but the breeding season involves several spawnings by each individual fish. These biological, developmental and reproductive characteristics are discussed in relation to current theories on evolution of life-historics.     

Use of a PCR method for controlling pure-breeding of honeybees Apis mellifera mellifera L. in the southern Urals

A key problem of honeybee (Apis mellifera mellifera) breeding in the Southern Urals is its cross-breeding with the Caucasian honeybee Apis mellifera caucasica. Mitochondrial DNA (mtDNA) in these subspecies differ in the length of a fragment localized between genes CO-I and CO-II, which can be used as a marker. A pair of 20-mer primers for PCR was chosen by means of computer design in order to determine the fragment size in both of the subspecies. The amplified fragment was shown to have a length of 350 bp in A. m. caucasica and 600 bp in A. m. mellifera. The difference in length results from the different ratio between two main elements P and Q, which comprise a major part of this sequence in these subspecies: a copy of P element and two copies of Q element in A. m. mellifera, and a copy of Q element only in A. m. caucasica. This sharply defined distinction allows us to use PCR for differentiating the subspecies, estimating the heterogeneity in the colonies, and rejecting queens in the selection process because of the maternal inheritance of the studied character. The nucleotide sequence of the amplified mtDNA fragment of A. m. mellifera was determined.     

Pre-pleistocene refugia and differentiation between populations of the caucasian salamander (Mertensiella caucasica)

A 350-bp fragment of the mitochondrial cytochrome-b gene was sequenced in the Caucasian salamander, Mertensiella caucasica, representing 10 populations from across its range along the Black Sea coast. Five haplotypes were discovered among 65 fragments analyzed, differing at 2-50 positions. The highest differentiation between haplotypes was observed in animals from the eastern part of the species' range (Borjomi) compared to those from the remainder of the species' range. Randomly amplified nuclear DNA revealed a pattern of spatial genetic variation similar to that of the mitochondrial genome. M. caucasica, as currently known, represents two evolutionary lineages that evolved independently, perhaps since the lower Pliocene. These lineages represent taxa, possibly to be described as species, distributed in the Borjomi area in central Georgia and in southwestern Georgia and northeastern Turkey. The multivariate analysis of morphological data did not reveal significant differences between the taxa. However, substantial morphological differentiation was observed within both lineages, showing parallel patterns in body proportions and coloration patterns. This variation is possibly associated with extant ecological conditions. Salamanders with reduced pigmentation from southwestern Georgia were not genetically distinguishable from neighboring populations.     

Modern concepts on the relationship between the agents causing plague and pseudotuberculosis

The authors present published data and their own findings on the relationship between Yersinia pestis and Y. pseudotuberculosis and on the origination of Y. pestis from Y. pseudotuberculosis. Study of microbiological and biochemical characteristics, external membrane protein spectra, and stability of chromosomal region of pigmentation brought the authors to a hypothesis that Y. pestis minor subspecies (ssp. caucasica, altaica, hissarica, ulegeica) which are characterized by selective virulence occupy an intermediate position between Y. pseudotuberculosis and basic species of Y. pestis.     

小麦族四个属模式种的醇溶蛋白分析

利用酸性聚丙烯酰胺凝胶电泳 (APAGE)对小麦族披碱草属、鹅观草属、猬草属和仲彬草属 4个属的模式种进行了醇溶蛋白电泳分析 ,结果表明 :(1 ) 4个模式种具有明显的醇溶蛋白遗传多样性 ,其种间醇溶蛋白多态性高达 92 .3 % ;(2 ) Elymus sibiricus和 H ystrix patula具有相似的醇溶蛋白带型 ,而 Roegneria caucasica和Kengyilia gobicola的带型基本相似 ,其醇溶蛋白图谱能够反映一定的系统关系 ;(3 )不同收集地的 E. sibiricus材料间也存在明显的醇溶蛋白遗传差异 ,新疆的 E. sibiricus具有较丰富的醇溶蛋白带纹 ,而甘肃的 E. sibiricus的醇溶蛋白带纹较少。