New data about distribution of lower Amur grayling <Emphasis Type="Italic">Thymallus tugarinae</Emphasis> and Baikal-Lena grayling <Emphasis Type="Italic">Thymallus</Emphasis> sp. (Thymallidae) in the basins of the upper Amur River and Zeya River

New findings of lower Amur grayling (Lower Amur grayling) Thymallus tugarinae and Baikal-Lena grayling Th. sp. (Th. baicalolenensis) in the basins of the upper Amur River and Zeya River are reported for 2010?2014. Lower Amur grayling has been registered in the tributaries of Argun River and in the middle stream of Ingoda River. Baikal-Lena grayling has been found for the first time in the headstream of Ingoda River. New data about the distribution of this species in the basin of upper stream of Zeya River are reported; particularly, Baikal-Lena grayling has been found in Okonon Lake; this is the first finding of a representative of Thymallidae family in the alpine lakes of the watershed area of Amur River. In the basins of upper Amur River and Zeya River, the summer ranges of upper Amur grayling Th. grubii grubii and lower Amur grayling overlap to some extent; on the other hand, the ranges of Baikal-Lena grayling and lower Amur grayling are disjoint. During the summer period, upper Amur grayling and Baikal-Lena grayling together inhabit the basin of upper stream of Zeya River, but only Baikal-Lena grayling has been found in the headstream of Zeya River. In the basin of upper Amur River (the headstream of Ingoda River), the joint range of these species is still unknown; the sympatric zone is located in Dzhermoltai River (the basin of Onon River).     

Finding of Amur sculpin <Emphasis Type="Italic">Mesocottus haitej</Emphasis> and <Emphasis Type="Italic">Cottus szanaga</Emphasis> (Cottidae) in Tugur River basin (Khabarovsk krai,Russia)

The first official finding of the Amur sculpin Mesocottus haitej and Cottus szanaga is reported for the basin of Tugur River (Shantarsky zoogeographical region). Previously, these species were known for this region from the literature only.     

Distribution of Masu Salmon <Emphasis Type="Italic">Oncorhynchus masou</Emphasis> (Salmonidae) in Amur River Basin

The presented data on the distribution of the masu salmon Oncorhynchus masou in the Amur River Basin are collected in 1976–2015. In the analyzed region the species’ spawning range includes the lower part of the Amur River basin from the rivers flowing into the Amur estuary to the basins of the Anyui and Amgun’ Rivers in their middle courses. The information on the catch of a masu salmon specimen in the Khor River Basin (approximately 1300 km from the Amur River mouth) in 2015 is presented. It is assumed that the total Amur population does not exceed several thousand of adult anadromous fish.     

Findings of the leaf beetles <Emphasis Type="Italic">Chrysolina tundralis</Emphasis> and <Emphasis Type="Italic">Chrysolina roddi</Emphasis> (Coleoptera,Chrysomelidae) in the middle part of European Russia

Two species of leaf beetles, Chrysolina tundralis and Ch. roddi, were found in the “Galich’ya Gora” Nature Reserve (the middle part of European Russia), 1200 and 700 km, respectively, from the main part of the ranges of these species. Adults and larvae of Ch. tundralis feed on Lamium purpureum, those of Ch. roddi feed on Seseli intermedia there. Diagnostic characters of the adults of both species are reported.     

New species of grayling <Emphasis Type="Italic">Thymallus tugarinae</Emphasis> sp. nova (Thymallidae) from the Amur River Basin

Data on a new species, low Amur grayling Thymallus tugarinae sp. nova, inhabiting tributaries of the lower and middle current of the Amur River, are presented. This species has been earlier equated with the Amur grayling T. grubii, described by Dybowski (1869) from the rivers Onon and Ingoda (the Upper Amur Basin). The new species differs from other representatives of the genus in the body coloration, the pattern on the upper fin, and certain morphological characters. On most of the Amur Basin, the grayling from the Lower Amur is sympatric with T. grubii and in its tributary Bureya River, also with the Bureya grayling T. burejensis. Individuals with intermediate traits are unknown, pointing to reproductive isolation. These data are supported by the results of molecular-genetic analysis (Froufe et al., 2003, 2005; Knizhin et al., 2004).     

Natural hybridization between two Japanese medaka species (<Emphasis Type="Italic">Oryzias latipes</Emphasis> and <Emphasis Type="Italic">Oryzias sakaizumii</Emphasis>) observed in the Yura River basin,Kyoto, Japan

To determine the actual state of hybridization between two Japanese medaka species (Oryzias latipes and Oryzias sakaizumii) in their natural environment, we used nuclear DNA markers at 10 loci to analyze 215 individuals from eight wild populations in the middle reaches of the Yura River basin in Japan, where the two species are sympatric. Despite large genetic differentiation between the two species, reproductive isolation between them could not be confirmed. We also discussed the formation of the current distribution patterns of the two species and their hybridization zone in the Yura River basin.     

Phylogenetic and taxonomic assessment of the endangered Cumberland bean, <Emphasis Type="Italic">Villosa trabalis</Emphasis> and purple bean, <Emphasis Type="Italic">Villosa perpurpurea</Emphasis> (Bivalvia: Unionidae)

Inadequate understanding of the phylogeography, taxonomy, and historical distribution of two critically imperiled freshwater mussels, Cumberland bean, Villosa trabalis, and purple bean, Villosa perpurpurea, has hindered management and recovery actions related to population restoration within their extant ranges. For more than 100 years, the purple-to-pink nacre of V. perpurpurea and white nacre of V. trabalis have been the only defining phenotypic characteristics used to distinguish each species. Genetic samples were analyzed from 140 individuals collected from 10 streams located in Virginia, Tennessee, and Kentucky, representing all known extant populations of each species. A 784-bp section of the mitochondrial DNA ND1 region was sequenced to assess the phylogeography and taxonomic validity of these taxa. Results of our phylogenetic analyses showed 100 % Bayesian posterior support for two distinct clades, one occurring in the Cumberland River basin and the other in the Tennessee River basin, separated by a mean genetic distance of 4 %. Mean genetic distances between haplotypes within each clade was <1 %. Among individuals from the Cumberland River basin, the nacre of shells was white to bluish-white, but in the Tennessee River basin, nacre graded from white to pink to dark purple; thus, nacre color is a variable and inconsistent character in nominal V. trabalis and V. perpurpurea occurring in the Tennessee River basin. Our data suggest that these morphologically similar species do not co-occur, as was previously believed. Instead, we conclude that the two species most likely share a common ancestor, but became isolated within each basin and experienced allopatric speciation. Updates to nomenclature, taxonomic placement, and recovery plans for the investigated species are needed.     

Environmental risk assessment of the egg parasitoid <Emphasis Type="Italic">Anaphes inexpectatus</Emphasis> for classical biological control of the <Emphasis Type="Italic">Eucalyptus</Emphasis> snout beetle, <Emphasis Type="Italic">Gonipterus platensis</Emphasis>

Classical biological control is a valuable tool against invasive pests, but concerns about non-target effects requires risk assessment studies. Potential non-target effects of Anaphes inexpectatus Huber and Prinsloo (Hymenoptera: Mymaridae) were assessed for a classical biological control programme against the Eucalyptus snout beetle, Gonipterus platensis (Marelli) (Coleoptera: Curculionidae). No-choice tests were conducted with 17 non-target species to assess host specificity, including 11 curculionids. In behavioural observations, A. inexpectatus showed no interest in any of the non-target species, but two weevil species were parasitised within five days of exposure, although at significantly lower rates than G. platensis. In choice tests, only one non-target, Hypera postica (Gyllenhal) (Coleoptera: Curculionidae), was parasitised, at a rate of 0.6%, while 50.0% of G. platensis eggs were parasitised. Based on the host specificity test results and the potential host fauna found in the target area, the likelihood of non-target effects resulting from the release of A. inexpectatus is considered to be negligible.     

Maintaining morphological specificity and genetic introgression in populations of the great tit <Emphasis Type="Italic">Parus major</Emphasis> and the Japanese tit <Emphasis Type="Italic">P. minor</Emphasis> in the middle Amur region

The ranges of the great tit Parus major and the Japanese tit P. minor overlap in the middle Amur region, where hybridization of these two species occur. These species have contacted for nearly a century on the western slope of the Malyi Khingan Ridge (the central part of the sympatry zone), but the great tit has colonized territories to the east of the ridge only in the last two decades. The percentage of the P. minor’s allele of intron 2 of the mioglobin gene has significantly increased from 8.9% in the west to 27.8% in the east in phenotypically major’s populations. Thus, the percentage of foreign mtDNA in P. major populations did not change significantly from west (6.2%, n = 120) to east (3.2%, n = 61). Simultaneous use of two genetic markers (one nuclear and the other mitochondrial) supports our conclusion on strong introgression in the populations of both species, which nevertheless maintain their morphological specificity in the contact zone.     

A laboratory study of host use by the cuckoo catfish <Emphasis Type="Italic">Synodontis multipunctatus</Emphasis>

The only known non-avian vertebrate obligate brood parasite is the cuckoo catfish (Synodontis multipunctatus), a Lake Tanganyikan endemic. The cuckoo catfish parasitizes Tanganyikan mouthbrooding cichlids, and under captive conditions, will also parasitize cichlids from other Rift Valley lakes. Here we examine the frequency of parasitism by the cuckoo catfish of Ctenochromis horei from Lake Tanganyika and three species from Lake Malawi and the greater Lake Victorian system in a laboratory setting. C. horei was parasitized significantly less (17%) than the allopatric species Haplochromis latifasciatus, Haplochromis nubilus, and Metriaclima estherae (combined parasitism rate of 28%). The lower rates of parasitism in C. horei may be due to differences in the mating ritual, oviposition (e.g., long periods of pseudo-spawning before actual oviposition), and behavioral adaptations (e.g., increased aggression towards the cuckoo catfish). The number of catfish eggs per parasitized brood was similar between C. horei, H. latifasciatus, H. nubilus, and M. estherae. Our results are comparable to findings from the field for C. horei parasitism frequency and number of cuckoo catfish per brood. We also analyzed the parasitism rate of the albino morph of Metriaclima zebra, a domestic strain. Parasitism rates and number of catfish per brood were the highest in the albino morphotype suggesting that the higher levels of parasitism may be related to lower aggressive behavior, lower visual acuity, or captive influence. Cuckoo catfish and mouthbrooding cichlids provide a model system for testing brood parasitism in a laboratory setting.     

Distribution,abundance, and size structure of Amur kaluga <Emphasis Type="Italic">Acipenser dauricus</Emphasis> and Amur sturgeon <Emphasis Type="Italic">A. schrenckii</Emphasis> in the Lower Amur and Amur Estuary

Distribution, population structure, and abundance of Amur kaluga Acipenser dauricus and Amur sturgeon A. schrenckii in the Lower Amur and Amur Estuary have been considered based on the materials of two surveys performed in 2011. Both species occur along almost the entire length of the Lower Amur and in major part of the Amur Estuary. The density of their aggregations has significantly decreased in most regions of the river if compared to the 1960s. In the Amur Estuary, A. dauricus and A. schrenckii are most abundant in freshwater and light salted water bodies of its western part. In 2011, the abundance and biomass of A. dauricus and A. schrenckii in the Lower Amur and Amur Estuary was 345000 specimens and 7110 tons and 289000 specimens and 1946 tons, respectively.     

Egg rejection behaviour in the great reed warbler (<Emphasis Type="Italic">Acrocephalus arundinaceus</Emphasis>): the effect of egg type

Egg discrimination in hosts of the common cuckoo Cuculus canorus is frequently studied by experimental parasitism, using model cuckoo eggs. We compared egg rejection behaviour of the great reed warbler Acrocephalus arundinaceus to either model cuckoo eggs made of plastic or painted real host eggs. We simultaneously parasitised host nests by two different egg types to simulate cuckoo parasitism. A previous study revealed very similar, ca. 70%, rejection rates against both of these egg types (beige or bluish background colour maculated with dark brown) when they were used for single parasitism. In the present study we showed 96% average rejection rates against these egg types when they were applied in multiple experimental parasitism, causing a more predictable output for rejection behaviour. Hard plastic eggs and painted real eggs were rejected at similar frequencies, and videotaping revealed that model egg rejection caused extra work for great reed warblers. We revealed a new type of rejection behaviour, when hosts tried to eject hard-shelled model cuckoo eggs: Hosts made little holes in the middle part of these plastic eggs by pecking them several times before ejection, as if seeking the possibility to pierce and hold these eggs in their bills. Painted real eggs were rejected by actually puncturing the eggshell and holding them in the bill during ejection. No instances of grasp ejection were recorded during filming. Most experimental eggs of either type were ejected within 1 day after the introduction of the eggs, indicating that hosts made their rejection decisions quickly. Our observations suggest the lack of plasticity in the mode and timing of ejection behaviour towards experimental cuckoo eggs of different types in great reed warblers.     

A new species of the genus <Emphasis Type="Italic">Boreophylloceras</Emphasis> Alekseev et Repin, 1998 (Ammonitida) from the Berriasian <Emphasis Type="Italic">kochi</Emphasis> zone of north-central Siberia

Study of the shells of phylloceratids from the kochi Zone (Berriasian) of north-central Siberia (Boyarka River, basin of the Kheta River) allowed their assignment to the genus Boreophylloceras Alekseev et Repin, 1998. A new species B. densicostatum is described.     

Reproduction and development of <Emphasis Type="Italic">Pholis picta</Emphasis> (Perciformes: Pholidae) and <Emphasis Type="Italic">Opisthocentrus zonope</Emphasis> (Stichaeidae)

In the Peter the Great Bay (the Sea of Japan), reproduction and embryonic larval development of Pholis picta and Opisthocentrus zonope are investigated. Both species spawn in November–December at the water temperature decreasing from 7.0 to 0.2°C. Fecundity of Pholis picta is 494–1228 eggs, and of Opisthocentrus zonope—368–1360 eggs. Both species lay eggs in empty shells of Gray mussel. Parent fish permanently stay in the shell but do not actively care for the eggs. Morphological changes in the process of embryogenesis are compared between the related species. Prolarvae and larvae are described for identification, with special attention to pigmentation. The spawning behavior of adult fish and behavior of prolarvae are described.     

Updating the geographical range of Terek barbel <Emphasis Type="Italic">Barbus ciscaucasicus</Emphasis> Kessler, 1877 (Cyprinidae) using the cytochrome <Emphasis Type="Italic">b</Emphasis> molecular marker

An analysis of the mtDNA marker allowed expanding the geographical range of the Terek barbel Barbus ciscaucasicus Kessler. The new findings expand the geographic range to more than 100 km southwards down to the Pirsaat River basin in Azerbaijan. It has been suggested earlier that the Pirsaat River was inhabited by the Kura barbel Barbus cyri De Filippi. The population of the Terek barbel in the Pirsaat River is isolated genetically from the barbels of the main geographic area of this species.     

Redescription of <Emphasis Type="Italic">Cottus sibiricus</Emphasis> and an estimation of differences between this species and <Emphasis Type="Italic">Cottus dzungaricus</Emphasis> (Cottidae)

The type specimens of Cottus sibiricus and C. dzungaricus as well as individuals from the Olkha River (Yenisei River basin) are studied. The diagnostic features of C. sibiricus are established. Comparative morphological and molecular analysis of divergence between C. sibiricus and C. dzungaricus demonstrates that the differences lie within the limits of one polymorphous species. The rank of Dzungarian sculpin is lowered to the subspecies, C. sibiricus dzungaricus.     

Redescription and systematic position of nominal loach species <Emphasis Type="Italic">Nemacheilus compressirostris</Emphasis> and <Emphasis Type="Italic">N. sibiricus</Emphasis> (Nemacheilidae)

Type specimens of nominal species Nemacheilus compressirostris Warpachowsky, 1897, and N. sibiricus Gratzianov, 1907, from the upper Ob River basin were redescribed, and lectotypes for both species were selected. Although some traits were not preserved well enough, it was established that both names should be classified with Barbatula cf. toni, corresponding to the “snub-nosed” morphotype fide Prokofiev (2007). None of the names are suitable for designation of the morph “tigris” fide Gundrizer (1975) and Prokofiev (2007). A comparison table of diagnostic traits of the genus Barbatula from the Asian part of the range was compiled.     

Complexes of <Emphasis Type="Italic">Formica</Emphasis> s. str. nests in the Darwin Nature Reserve and causes of their degradation

Nest complexes of Formica ants were studied in the Darwin Nature Reserve, in Rybinsk Reservoir basin (Vologda and Yaroslavl Provinces). A strong negative influence of wild boars was demonstrated based on the data of 1997–2012. Boars damage ant nests, which may lead to their complete destruction. The adverse influence of boars is intensified in the years with high water levels in the reservoir, when the boars cannot feed in the temporary inundation zone and thus increase their impact on the forest and ant nests. Due to the long succession of highwater years since 2004 and the resulting strong impact of wild boars, the number and size of ant nests drastically decreased, and the abundance and biomass of Formica ants in forest ecosystems were reduced.