Myxobolus filamentum sp. n. was found infecting gill filaments of three of 39 Brycon orthotaenia Günther specimens examined (8%), which were taken from the river São Francisco in Minas Gerais state, Brazil. Plasmodia of the parasite were white and long, measuring 5 mm in lenght. Mature spores of M. filamentum sp. n. were oval from the frontal view and biconvex from the lateral view, measuring 7.5-9.7 µm (9.0 ± 0.3 µm) in length and 5.2-7.3 µm (6.2 ± 0.4 µm) in width. The polar capsules were elongated and equal in size, measuring 3.8-5.5 µm (4.7 ± 0.3 µm) in length and 1.3-2.2 µm (1.7 ± 0.1 µm) in width. The development of the parasite led to compression of the adjacent tissues and inflammatory infiltrate with granulocytic cells. Ultrastructural observation revealed that the plasmodia were delimited by two membranes, which had numerous and extensive pinocytotic channels extending into the wide ectoplasm zone. The plasmodial wall exhibited abundant villi-like projections and a thin layer of granular material prevented direct contact between the plasmodial wall and the host tissue. Phylogenetic analysis, based on 18S rDNA, showed M. filamentum sp. n. as a sister species of Myxobolus oliveirai Milanin, Eiras, Arana, Maia, Alves, Silva, Carriero, Ceccarelli et Adriano, 2010, a parasite of other fish species of the genus Brycon Müller et Troschel from South America., Juliana Naldoni, Suellen A. Zatti, Kassia R.H. Capodifoglio, Tiago Milanin, Antônio A.M. Maia, Marcia R.M. Silva, Edson A. Adriano., and Obsahuje bibliografii
Copepods of the genus Achtheinus Wilson, 1908 (Pandaridae) are parasites of elasmobranchs that attach to their fins, gill slits and around the nostrils. Specimens of Achtheinus pinguis Wilson, 1912 were collected and examined using histology and scanning electron microscopy to determine their way of attachment to the host and the possible effect on the host. They insert their antennae deep into the dermis of the shark's skin, which causes the most damage due to possible tissue compression and/or fibrosis as well as rupture of the connective tissue. Additionally, the presence of the copepod on the skin causes cell erosion of the epidermal cells and thus reduces the number of epidermal layers. The maxillipeds are used to attach to the placoid scales that cover the shark's skin and probably serve to keep the copepod and inserted antennae in position. This is accomplished by the insertion of the placoid scales into the flaccid corpus of the maxillipeds. Observed damage seems to be negligible to the shark apart from the possibility of secondary infection., Susan M. Dippenaar, Anine Jordaan., and Obsahuje bibliografii
The use of species distribution models (SDMs) to predict the spatial occurrence and abundance of species in relation to environmental predictors has been debated in terms of species’ ecology and biogeography. The predictive power of these models is well recognized for vertebrates, but has not yet been tested for invertebrates. In this study, we aim to assess the use of SDMs for predicting local abundances of invertebrates at a macroscale level. A maximum entropy algorithm was used to build SDMs based on occurrence records of 61 species of butterflies and bioclimatic information with a 30 arc second resolution. Predictions of habitat suitability were correlated with butterfly abundance data derived from independently conducted field surveys in order to check for a relationship between the predictions of the model and local abundances. Even though the model accurately described the current distributions of the species in the study area at a macroscale, the observed occurrences of the species (i.e. presence/absence) recorded by the field surveys differed significantly from the model’s predictions for the corresponding grid cells. Moreover, there was no correlation between observed abundance and the model’s predictions for most species of butterflies. We conclude that the spatial abundance of butterflies cannot be predicted from environmental suitability modelled at a resolution as large as in this study. Using the finest scale bioclimatic information currently available (i.e. 30 arc seconds) it is not adequate to predict species abundances as structural and ecological factors as well as climatic patterns acting at a smaller scale are key determinants of the occurrence and abundance of invertebrates. Therefore, future studies have to account for the role of the resolution in environmental predictors when assessments of spatial abundances via SDMs will be conducted., Katharina J. Filz, Thomas Schmitt, Jan O. Engler., and Obsahuje seznam literatury
Species-level problems in the Aphis (Bursaphis) complex are reconsidered based on the partial sequences of the mitochondrial cox1 gene together with morphological and ecological data. This indicates that the American species A. oenotherae is a complex of four species (A. oenotherae, A. holoenotherae, A. costalis and A. neomexicana) and the taxonomic status of the species couples A. varians - A. manitobensis and A. epilobii - A. grossulariae require further clarification. Aphis sp. (USA: California, Oregon) of Blackman & Eastop (2006, p. 415) deserves the status of a species provided there is information on its host association and life cycle. Partial cox1 sequences might be misleading when used as standard DNA barcodes of aphid species of the subgenus Bursaphis. and Rimantas Rakauskas, Jurga Turčinavičienė, Jekaterina Bašilova.
The whipworms, i.e. parasitic nematodes of the genus Trichuris Roederer, 1761, infect a variety of mammals. Apparently low diversity of primate-infecting species of Trichuris strongly contrasts with the high number of species described in other mammalian hosts. The present study addresses the diversity of whipworms in captive and free-ranging primates and humans by analysing nuclear (18S rRNA, ITS2) and mitochondrial (cox1) DNA. Phylogenetic analyses revealed that primate whipworms form two independent lineages: (i) the Trichuris trichiura (Linnaeus, 1771) clade comprised of genetically almost identical whipworms from human and other primates, which suggests the ability of T. trichiura to infect a broader range of primates; (ii) a clade containing primarily Trichuris suis Schrank, 1788, where isolates from human and various primates formed a sister group to isolates from pigs; the former isolates thus may represent of more species of Trichuris in primates including humans. The analysis of cox1 has shown the polyphyly of the genera Trichuris and Capillaria, Zeder, 1800. High sequence similarity of the T. trichiura isolates from humans and other primates suggests their zoonotic potential, although the extent of transmission between human and other non-human primates remains questionable and requires further study., Jana Doležalová, Miroslav Oborník, Eva Hajdušková, Milan Jirků, Klára J. Petrželková, Petra Bolechová, Cristina Cutillas, Rocio Callejón, Jozef Jaroš, Zuzana Beránková, David Modrý., and Obsahuje bibliografii
1_Many butterfly target species are associated with early successional stages of grasslands. The Blue-spot Hairstreak, Satyrium spini (Denis & Schiffermüller, 1775), is a target species of grasslands. However, it feeds on Common Buckthorn (Rhamnus cathartica), which is associated with late successional stages of grasslands. If S. spini would also be restricted to late seral stages, there might be a management dilemma due to the contrasting requirements of S. spini and other target species. The aim of this study was to determine the oviposition preference of S. spini in calcareous grasslands, and to give management recommendations to promote this species. Therefore, we studied the oviposition microhabitats of S. spini at three representative patches of the Diemel Valley (Central Germany) by comparing environmental conditions on occupied and control host plants. In total we surveyed 1,889 host plants. Altogether we found 148 batches of S.spini on them containing 396 eggs. Most of the eggs were on plants that grew under the warmest conditions. Females preferred to lay eggs on small (< 1.3 m) shrubs of Rh. cathartica fully exposed to the sun growing on steep south- and west-facing slopes., 2_This butterfly showed no difference in its preference for bushes growing in hedges or solitarily. About 80% of the batches of eggs were laid on the upper surface of a twig fork close to the surface of the ground (< 1 m). Our study showed that S. spini is a species characteristic of mid-successional stages of calcareous grasslands. The survival of suitable habitats for S. spini depends on regular management. To achieve this we recommend traditional rough grazing with sheep and goats, which creates open grasslands with small Rhamnus plants. In addition, the shrubs in tall hedges bordering calcareous grasslands should be subjected to cutting on a rotating basis., Franz Löffler, Gregor Stuhldreher, Thomas Fartmann., and Obsahuje seznam literatury
a1_Cities contain only a low representation of natural and semi-natural habitats, existing in fragments surrounded by built-up areas. In 2003-2004, we surveyed butterflies and Zygaenidae moths in 21 reserves and 4 parks within the city of Prague, Czech Republic, situated from the periphery to city centre. A total of 85 species (47% of the Czech fauna of the study groups) was detected, 22 of them being of conservation concern. Ordination analyses of the local assemblages revealed that the richest sites were large, situated far from the city centre, on alkaline bedrocks, south- to southwest oriented, and hosting high numbers of vegetation types and vascular plant species. We then used generalised linear models to fit responses of individual species to the main ordination gradient, corresponding to increasing urbanisation. Out of 60 species that met criteria for the modelling, none responded positively to urbanisation. Twenty displayed negative linear response; these urban avoiders contained a surplus of mesophilous species presumably preferring rural landscapes. Further 29 species (suburban adaptable) responded in domed manners, peaking at the city periphery. Prevailing among them were xerophilous specialists inhabiting large grassland reserves at the Prague outskirts. Finally, eleven urban tolerant species did not respond to urbanisation at all, containing three highly mobile species, three xerothermophilous specialists, and five species utilising shrubs or trees and finding suitable conditions even in urban parks. Suburban adaptable butterflies apparently benefit from such suburban environments as gardens, road or railway verges, collectively increasing the connectivity of remnants of seminatural habitats. The fact that arboreal species persist even in urban parks, whereas common grassland species are absent there, implies that the quality of urban habitats might be increased by a more sensitive management of, a2_urban green spaces, such as leaving aside small temporary fallows or adapting lawns mowing schemes., and Martin Konvicka, Tomas Kadlec.
by O. Nordgaard. The protist plankton and the diatoms in bottom samples / by E. Jørgensen., KČSN - signatura S-E 128, Poškozené desky., and Desky skenovány z jiné signatury. S-E 128
The sex determination cascades in insects are diversified at the top of the cascade, where different primary molecular signals are employed, while at the bottom of the cascades, particularly the doublesex genes, are highly conserved. Here, we identified the doublesex ortholog (Btau-dsx) of Bactrocera tau, a pumpkin fruit fly, and found that Btau-dsx is composed of six exons and five introns with an additional short "m" exon located in the second intron. Btau-dsx is different from its orthologs in most dipteran insects: Its pre-mRNA is sex-specifically spliced to yield three (two male and one female) instead of two transcript variants. The two deduced proteins produced by the male-specific transcripts are a functional (Btau-DSXM1) and a truncated (Btau-DSXM2) protein, while the female-specific transcript produces the functional Btau-DSXF protein. These three proteins contain all conserved domains except Btau-DSXM2 which has no OD2 domain. The female-specific transcript is detected in both fertilized and unfertilized eggs and in both somatic and germ cells of the adult females, while the male-specific transcript is detected only in fertilized eggs and in the abdominal tissues and testes of adult males. The presence of the Btau-dsxM1 transcript in fertilized eggs at the early syncytium stage suggests that in XY embryos, the Y-linked M factor gene may function quite soon after fertilization to alter the splicing pattern of Btau-dsx pre-mRNA from the female-specific to the male-specific mode. Injection of Btau-dsxF dsRNA into recently emerging females can reduce the expression of vitellogenin (Btau-Vg) and causes some defects in the ovaries, indicating that Btau-dsxF works upstream of Btau-Vg., Thanaset Thongsaiklaing, Hataichanok Passara, Mingkwan Nipitwathanaphon, Lertluk Ngersiri., and Obsahuje bibliografii