Global Spread of the Eel Parasite Gyrodactylus Anguillae (Monogenea)

Gyrodactylus anguillae is known from four continents, and intraspecific variation in the morphology of specimens from each continent is negligible. However, morphological characters alone may not always be adequate for recognizing populations that have been isolated geographically over evolutionary time. We were unable to obtain specimens from Northeast Asia, but G. anguillae collected from North America, Europe and Australia had identical ribosomal DNA sequences (ITS1-5.8SrRNA-ITS2 region). This lack of even minor genetic variation in populations from three remote continents leads us to conclude that they share a contemporary common ancestor. This is one of at least five pests of eels to have invaded new continents as a result of the eel trade in the last four decades; these other known eel pests include Pseudodactylogyrus spp. (Monogenea) and Anguillicola spp. (Nematoda). Their dispersal has probably been secondarily augmented by longshore migration of infected eels, and perhaps also by transportation in ballast waters. The only other known gyrodactylid from eel gills, G. nipponensis from Japanese eel, is not closely related to G. anguillae, because the ITS1 region of the former is short (370 bases) and that of the latter long (685 bases). G. anguillae probably originated in Europe, because it was recorded there over 40 years ago, before the development of the international eel trade. We predict that the worm has a high potential to invade eel populations in East Africa, Southeast Asia, and New Zealand.     

Redescription of Ilyocryptus tuberculatus Brehm, 1913 (Anomopoda,Branchiopoda)

The morphology of Ilyocryptus tuberculatus Brehm, 1913 is redescribed, based on material from the Niger basin, Africa. The species name was given by Brehm erroneously, because under an optical microscope he mistook internal structures (the columns between the outer and inner walls of the valves) for the tubercules on the valve surface. But this species is undoubtedly valid, and `incorrect' species names must be conserved. Differences between I. tuberculatus and the most similar I. agilis (probably absent from the majority of African waters), I. spinifer (common in Africa), and some other species are discussed. Currently, I. tuberculatus is known for the Central African Republic, Mali and Niger.     

Validation of the occurrence of the American eel Anguilla rostrata (Le Sueur, 1817) in free-draining European inland waters

The screening of 2,735 eels from European waters and aquaculture farms was conducted using mitochondrial Cytochrome b and 16S rRNA gene fragments amplified by polymerase chain reaction. Reaction products were either sequenced directly or subjected to analysis using restriction fragment length polymorphism which resulted in species-specific restriction patterns. Beside the expected European eel, Anguilla anguilla (Linnaeus, 1758), the American eel, Anguilla rostrata (Le Sueur, 1817), was also identified in samples from both aquaculture (N = 40 out of 1,025) and from natural waters (N = 44 out of 1,710). The life stages of American eels identified from several German waters draining to either the Baltic Sea and the North Sea ranged from elver to silver eels. This indicates that stocking with glass eels or elvers must have occurred several times most likely in the period from 1998 to 2002. The application of a fast and precise method for species identification and genetic monitoring of eels delivered for stocking is therefore essential for maintaining the autochthonous species composition in future. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Genetic structure of the rare and endangered moss <Emphasis Type="Italic">Campylopus oerstedianus</Emphasis> (Dicranaceae) in Europe

The genetic structure, diversity and phylogeography of the moss species Campylopus oerstedianus in Europe was studied, based on the ITS region of the nrDNA of nine selected European populations. Although this species is only known in sterile stage, long-distance dispersal and gene flow among populations seem to be present within Europe. High levels of genetic differentiation between the investigated Greek population and the western European populations indicate a long lasting isolation. The populations from France and Switzerland root together and supposedly have a common origin. From the French populations, the one from the Pyrenees is the most basal one and the populations in the Massif Central and the Vosges Mts can be derived from it. This indicates relatively recent dispersal of the species from the Mediterranean to the north, in spite of the lack of sporophytes and the fact that the type of the dispersed propagules and their vectors are not obvious.     

Geographic differentiation in wing shape inDrosophila melanogaster

Genetic variation of a suite of 12 morphometric wing characters was examined in 16 natural populations ofDrosophila melanogaster from Eastern Europe and Central Asia using principal component analysis. The posterior wing compartment was found to differ in shape between the Eastern European and Central Asian populations. This result is in agreement with data on wing shape variation from exposure to high and low temperatures under laboratory conditions.     

Genetic analysis reveals two distinct Sacramento splittail (<Emphasis Type="Italic">Pogonichthys macrolepidotus</Emphasis>) populations

The Sacramento splittail is an endemic cyprinid fish of the San Francisco estuary and its tributaries, which is a highly manipulated, constantly changing ecosystem. Splittail is the only extant member of its genus and is listed as a federal and California Species of Special Concern due to uncertainties regarding long-term abundance trends. Determining population structure for splittail is important because unique populations may contain different adaptive genetic variation, which can allow one population to persist through future environmental or demographic stochasticity while others become extirpated. To assess splittail population structure, 13 microsatellite markers were used to genotype 489 young-of-year splittail from five major rivers draining into the estuary: Cosumnes, Napa, Petaluma, Sacramento, and San Joaquin Rivers. Two genetically distinct populations were found to exist within our study region; one largely comprised of splittail collected from the Petaluma and Napa Rivers and the second comprised of splittail collected from tributaries in Californiaȁ9s Central Valley: Cosumnes, Sacramento, and San Joaquin Rivers. These results were replicated in two consecutive years with both distance and model-based algorithms. The genetic distinction between these two populations appears correlated with salinity differences between migratory regions and spawning grounds. Splittail from the Petaluma River exhibited a significantly higher degree of differentiation from the Central Valley population than did Napa River splittail. Our results suggest on-going monitoring programs are probably highly biased towards sampling splittail from the Central Valley population. Understanding population dynamics of splittail could be improved if monitoring programs were expanded to include all splittail populations.     

Taxonomic status of three nominal species of Indo-Pacific symphurine tonguefishes (Symphurus: Cynoglossidae: Pleuronectiformes)

The taxonomic status of three rarely captured, nominal species of Indo-Pacific symphurine tonguefishes,Symphurus trifasciatus (Alcock, 1894),S. microrhynchus (Weber, 1913), andS. holothuriae Chabanaud, 1948, is resolved.Symphurus microrhynchus, previously known only from three specimens, is redescribed based on 12 specimens.Symphurus holothuriae, previously reported only from the holotype, is a junior subjective synonym ofS. microrhynchus. Symphurus trifasciatus is redescribed based on six specimens, including the lectotype designated in this study.Symphurus microrhynchus is distinguished from congeners by a combination of meristic features, head and opercle shape, dorsalfin position, and features of its pigmentation. The species occurs in relatively shallow tropical waters from Zanzibar through French Polynesia (the only reported occurrence of a shallow-waterSymphurus from a locality on the Pacific Plate), including Indonesia, Papua New Guinea, Vietnam, and northwestern Australia.Symphurus trifasciatus, known from deep waters along both coasts of the Indian subcontinent and adjacent waters, has an overall similarity in body shape and meristic features reminiscent of those inS. microrhynchus, but differs notably in having a longer and wider head, a distinctive opercle shape, number of scale rows on the head, and pigmentation pattern.     

Redescription of Diaphanosoma dubium Manuilova, 1964 (Branchiopoda: Ctenopoda: Sididae), and description of a new,related species

The poorly known D. dubium Manuilova is redescribed on extensive material from more than 80 populations from the Russian Far East, Central Asia, Mongolia, China, Japan, Vietnam, the Philippines, Thailand, Malaysia, Bangladesh, India and Sri Lanka. Its morphological variability and geographical distribution are analysed and supplemented by notes on biology. The conspecificity of morphologically different distant populations is discussed. In the northern part of its range, D. dubium was long confused with D. brachyurum or D. leuchtenbergianum, and in the south with D. modigliani. It seems that the recent appearance of D. dubium in fish ponds of Uzbekistan and Kazakhstan was an introduction, together with Far Eastern fish. D. pseudodubium sp.nov., close to but markedly different, is described from two lakes in the lower Amur river system. D. dubium, D. pseudodubium, D. tropicum and D. modigliani s. str. form a group of related species, widely distributed in Eastern and Southern Asia.     

Genetic differentiation of metallicolous and non-metallicolous Armeria maritima (Mill.) Willd. taxa (Plumbaginaceae) in Central Europe

This study investigates the genetic differentiation within the Central European Armeria maritima (Mill.) Willd. complex with special reference to the metallicolous populations using AFLP markers. Our sampling comprised all metallicolous (ssp. halleri, hornburgensis, bottendorfensis, eifeliaca, calaminaria), and non-metallicolous taxa (ssp. maritima, elongata, alpina). Geographical and genetic distances between populations were moderately positively correlated. Genetic variability of metallicolous and non-metallicolous populations was not significantly different. Lowland populations were clearly differentiated from the alpine populations. Within the lowland group metallicolous and non-metallicolous populations were not genetically differentiated. All lowland populations show a regional differentiation and close relationships to ssp. elongata. Thus, the metallicolous taxa should not be maintained as subspecies. Likewise, their treatment as varieties of a ssp. halleri s.l. is critical because this taxon cannot be consistently characterized throughout its geographical range and may be an artefact itself. If a taxonomical recognition should be considered necessary it is advisable to treat the microendemics as varieties of ssp. elongata.     

Change of adaptations from entomophily to autogamy inParahebe linifolia (Scrophulariaceae)

Measurements of 16 inflorescence and floral characters from 5 populations ofParahebe linifolia (3 of entomophilous subsp.linifolia; 2 of autogamous subsp.brevistylis) were analysed. Discontinuous variation of three characters associated with the mechanisms of pollination suggests these are under strong selection towards different optima in each subspecies. Variation which is continuous and associated with the type of pollination in 4 characters mostly concerned with display is thought to result from selection for metabolic economies, counteracted strongly in subsp.linifolia, but less so in subsp.brevistylis, by selection for display. Nine more characters vary in a way not known to be associated with the two pollination systems.     

Parastenocaris lorenzae n.sp., and first record of Parastenocaris glacialis Noodt (Copepoda,Harpacticoida) from Italy

Parastenocaris lorenzae n.sp. is described from rhithrostygal of the Sangro river (Abruzzo, Central Italy). Parastenocaris glacialis Noodt, 1952 is for the first time recorded from Italy. The presence of borealpine elements in ground waters of Central Apennines is briefly discussed.Contribution to the knowledge of the groundwater fauna in central Research supported by grants from M.P.I. (40%) and C.N.R. (Gruppo and southern Italy: XLIV. Nazionale di Biologia Naturalistica).     

Rapid hyperthyroidism-induced adaptation of salmonid fish in response to environmental pollution

The streams draining volcanic landscapes are often characterized by a complex series of factors that negatively affect hydrobionts and lead to declines in their populations. However, in a number of cases, a range of rapid adaptive changes ensure the resilience of hydrobiont populations. Here, we present both field and experimental data shedding light on the physiological basis of adaptation to heavy metal contamination in populations of Dolly Varden charr (Salvelinus malma) differing in duration of isolation in volcanic streams. The study reveals that isolated populations have a physiological phenotype that distinguishes them from populations inhabiting clean waters. They are characterized by a hyperthyroid status accompanied by an increased metabolic rate, elevated activity of antioxidant enzymes, decreased ionic conductivity of tissues and reduced stored energy reserves. Our experimental data reveal that hyperthyroidism is an adaptive characteristic enhancing the resistance to heavy metal contamination and shaping the evolution of these populations. The similarity of physiological, developmental and morphological changes in isolated populations suggests a common source and mechanisms underpinning this case of ‘evolutionary rescue’. Thus, populations of S. malma trapped in volcanic streams represent a genuine case of rapid endocrine-driven adaptation to changing environmental stimuli.     

Spatial patterns in the biology of the chokka squid, Loligo reynaudii on the Agulhas Bank, South Africa

Although migration patterns for various life history stages of the chokka squid (Loligo reynaudii) have been previously presented, there has been limited comparison of spatial variation in biological parameters. Based on data from research surveys; size ranges of juveniles, subadults and adults on the Agulhas Bank were estimated and presented spatially. The bulk of the results appear to largely support the current acceptance of the life cycle with an annual pattern of squid hatching in the east, migrating westwards to offshore feeding grounds on the Central and Western Agulhas Bank and the west coast and subsequent return migration to the eastern inshore areas to spawn. The number of adult animals in deeper water, particularly in autumn in the central study area probably represents squid spawning in deeper waters and over a greater area than is currently targeted by the fishery. The distribution of life history stages and different feeding areas does not rule out the possibility that discrete populations of L. reynaudii with different biological characteristics inhabit the western and eastern regions of the Agulhas Bank. In this hypothesis, some mixing of the populations does occur but generally squid from the western Agulhas Bank may occur in smaller numbers, grow more slowly and mature at a larger size. Spawning occurs on the western portion of the Agulhas Bank, and juveniles grow and mature on the west coast and the central Agulhas Bank. Future research requirements include the elucidation of the age structure of chokka squid both spatially and temporally, and a comparison of the statolith chemistry and genetic characterisation between adults from different spawning areas across the Agulhas Bank.     

Genetic characterization of common carp (Cyprinus carpio) populations from Greece using mitochondrial DNA sequences

Wild common carp from two lakes and two rivers in Greece were genetically characterized with sequencing analysis of two mitochondrial DNA segments: cytochrome b (1119 bp) and D-loop (646 bp). A total of 9 variable singleton sites and 7 unique haplotypes were detected. A common haplotype was found in three out of the four populations examined, which seems to be the ancestral one and represents the European origin of common carp from Greece. This haplotype could be also justified by the introductions reported with individuals belonging to the Central European race, into many natural habitats in Greece. Limited genetic variation — in Evros and Aliakmonas populations — could be due to bottleneck effects and small effective population sizes, whereas the different haplotypes found in Lake Volvi could represent different common carp stocks. Values of sequence divergence among Greek haplotypes ranged from 0.0006 to 0.0023. The Neighbour-Joining (NJ) phylogenetic tree constructed based on the combined sequences, reveals that the populations of common carp from Greece belong to the European group of populations — which is highly divergent from the South East-Asia cluster — and to the subspecies Cyprinus carpio carpio.     

Genetic variation in populations of <Emphasis Type="Italic">Allothrombium pulvinum</Emphasis> (Acari: Trombidiidae) from Northern Iran revealed by mitochondrial <Emphasis Type="Italic">cox</Emphasis>I and nuclear rDNA <Emphasis Type="Italic">ITS</Emphasis>2 sequences

Allothrombium pulvinum Ewing is a common natural enemy of aphids and some other arthropods. So far, there are no studies that have addressed genetic variation of this predatory mite. We investigated genetic variation of A. pulvinum across its whole known range in Iran. A 410 bp portion of the mitochondrial cytochrome c oxidase subunit I gene (coxI) and 797–802 bp portion of the internal transcribed spacer 2 of rDNA (ITS2) were sequenced for 55 individuals from 11 populations, resulting in 12 and 26 haplotypes, respectively. In the coxI region, haplotype and nucleotide diversities varied among populations from 0.00 to 0.90 and from 0.0000 to 0.0110, respectively. In the ITS2 region they varied from 0.20 to 0.91 and from 0.0006 to 0.0023, respectively. For both gene regions the highest haplotype and nucleotide diversities were detected in population Mahmoud Abad from northern Iran. Statistically significant population differentiation (F _ST) was detected in most pair-wise population comparisons. The results of population differentiation for both gene regions were generally congruent indicating that A. pulvinum from Iran consists of genetically different populations. This suggests that A. pulvinum comprises at least two geographically distinct populations or even more than one species. This study is an initial step towards understanding genetic variation of A. pulvinum, a taxon for which little molecular information is available. More intensive sampling and analysis of additional DNA regions are necessary for more detailed classification of this taxon.     

Selective adaptation to copper of populations ofAgrostis tenuis andFestuca rubra (Poaceae)

Populations ofAgrostis Tenuis andFestuca rubra, tolerant and non-tolerant towards Zn and Pb, were studied in regard to their adaptability by natural selection, towards a third metal (Cu) and the time required for the appearance of such tolerance. It was found that Zn and Pb tolerant and non-tolerant populations are likely to select the character of Cu-tolerance within the course of only one generation. More specifically, Zn and Pb tolerant populations show a better adaptability compared with non-tolerant ones. The amount of tolerance to copper obtained by artificial selection is comparable with that of populations growing naturally on copper mines.     

Biomonitoring Survey of Trace Metal Pollution in Streams of a Catchment Draining a Zinc and Lead Mining Area of Upper Silesia,Poland Using the Amphipod Gammarus fossarum

We have used accumulated metal concentration data to investigate variability in the bioavailabilities of cadmium, copper, lead, zinc and iron to the amphipod Gammarus fossarum inhabiting the Biala Przemsza river system draining an area of lead and zinc mining. The highest bioavailabilities of most of the metals were found in a stream carrying water from mine drainage and flotation processes. Significant amounts of bioavailable cadmium entered via another stream receiving waters from ore processing. The bioavailabilities of copper varied little, indicating the lack of a local point source of entry. All metals other than copper showed seasonal variations with the highest concentrations recorded in October. Comparative data show the Biala Przemsza system to be contaminated with cadmium, lead, zinc and iron. The data presented exemplify metal concentration ranges in G. fossarum inhabiting industrial areas, and can be used as a reference for future surveys involving this species in Central Europe.     

The contact zone between two migration routes of silver fir,Abies alba (Pinaceae), revealed by allozyme studies

Enzyme data from 35 populations or regional samples ofAbies alba were obtained from different regions of Austria and Bavaria. The genetic analysis revealed a clear differentiation between the western and the north/eastern populations. A rather narrow transition zone (the river valleys of Salzach and Traun) with genetically intermediate populations connects these two regions. This west-east differentiation can be interpreted as the result of distinct migration routes from a glacial refuge in Central Italy. The transition zone is assumed to be the contact area of two routes north of the Alps. Each migration route of silver fir parallels the distribution range ofCardamine trifolia (east) andAposeris foetida (west) respectively. It is supposed that these two species were already associated with silver fir during colonization.Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday     

Stygofauna of the Canary Islands, 6 A new Rhipidogammarus (Crustacea,Amphipoda) from Tenerife: first record of the genus outside the Mediterranean region and its biogeographic implications

The discovery of a new species ofRhipidogammarus, Rh. nivariae n. sp., in water supply shafts of Tenerife (Canary Islands), presents an interesting biogeographic problem. Up to now, members of the genus were known exclusively from stygohabitats in the peri-Mediterranean belt. Its sister-genus is found in very shallow waters of the Mediterranean, and on morphological grounds the genus seems to have got adapted only fairly recently to continental hypogean waters. The occurrence of a member ofRhipidogammarus on an oceanic island like Tenerife can be explained by one of the following two scenarios: (1) Tenerife is a fragment of the African plate, or (2) the island's volcanic outcrops arose from a very shallow submarine bank and drifted later into deeper waters.     

The First Finding of the Actinia Synandwakia hozawai in the Sea of Okhotsk

The finding of the actinia Synandwakia hozawai in the coastal waters of northern Sakhalin (Sea of Okhotsk) suggests a wider range of this species, which was previously only known to inhabit the coastal waters of eastern Japan. Data are presented on the morphology of the S. hozawai specimen from the Sea of Okhotsk and the types of its nematocysts.