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1.
A new microsporidium, Liebermannia patagonica n. gen., n. sp., is described from midgut and gastric caecum epithelial cells of Tristira magellanica, an apterous grasshopper species of southern Patagonia, Argentina. L.patagonica is diplokaryotic, apansporoblastic, homosporous, and polysporoblastic. Transitional (from merogony to sporogony) stages and sporonts of L. patagonica were surrounded by host rough endoplasmic reticulum. The ovocylindrical spores measured 2.9 +/- 0.09 x 1.2 +/- 0.04 microm (fresh, n = 50), and they had an isofilar polar filament of only three coils and a cluster of tubules instead of a classical posterior vacuole. Prevalence was high (up to 80.6%) at the type locality for the four years sampled . Maximum likelihood , neighbor joining, maximum parismony analyses of the small submit rDNA all placed L.patagonica(Accession No. DQ 239917) in one with Orthosomella operophterae. 相似文献
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The complete nucleotide sequence of the mitochondrial genome (mitogenome) of Gomphocerus tibetanus Uvarov, 1935 (Orthoptera: Acrididae: Gomphocerinae) was determined. It is 15,571 bp in length and contains 74.8% A + T. All Gomphocerus tibetanus protein-coding sequences start with a typical ATN codon. The usual termination codons (TAA and TAG) were found from 13 PCGs except COI and COII which took incomplete codon T as termination codons. All tRNA genes could be folded into the typical cloverleaf secondary structure, except tRNASer(AGN) lacking of dihydrouridine (D) arm. The sizes of the large and small ribosomal RNA genes are 1313 and 822 bp, respectively. The A + T content of the A + T-rich region is 82.3%. A preliminary analysis on characteristics of Gomphocerinae mitogenome was made by comparision among three Gomphocerinae mitogenomes and Locusta migratoria. 相似文献
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G.D. Stentiford K.S. Bateman J. Moss K.S. Reece 《International journal for parasitology》2010,40(12):1433-1446
In this study we describe, the first microsporidian parasite from nephropid lobsters. Metanephrops challengeri were captured from an important marine fishery situated off the south coast of New Zealand. Infected lobsters displayed an unusual external appearance and were lethargic. Histology was used to demonstrate replacement of skeletal and other muscles by merogonic and sporogonic stages of the parasite, while transmission electron microscopy revealed the presence of diplokaryotic meronts, sporonts, sporoblasts and spore stages, all in direct contact with the host sarcoplasm. Analysis of the ssrDNA gene sequence from the lobster microsporidian suggested a close affinity with Thelohania butleri, a morphologically dissimilar microsporidian from marine shrimps. Whilst morphological features of the lobster parasite are consistent with members of the family Nosematidae, molecular data place the parasite closer to members of the family Thelohanidae. Due to the contradiction between morphological and molecular taxonomic data, we propose the erection of a new genus in which the lobster parasite is the type species (Myospora metanephrops). Furthermore, we recommend the erection of a new family (Myosporidae) and a new order (Crustaceacida) to contain this genus. The taxonomic framework presented could be further applied to the re-classification of existing members of the Phylum Microsporidia. 相似文献
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The visual behavior of adult Melanoplus sanguinipesF. (Orthoptera: Acrididae) was investigated by placing individuals in the center of an arena and recording their orientation responses to visual targets at the perimeter of the arena. Targets that reflected more 540- to 570-nm light were approached more frequently; however, when reflectance in the 540 -to 570-nm region was combined with reflectance in the 400- to 520-nm region, orientation responses were reduced significantly. This suggests that spectral discrimination in M. sanguinipesinvolves at least two classes of photoreceptors, which respond to different regions of the wavelength spectrum. In addition, grasshoppers oriented to vertical, but not horizontal, contrasting stripes. However, when vertical stripes were added to targets reflecting 520- to 650-nm light, responses to verticals on these targets were not enhanced relative to verticals presented against a target background of 400- to 520-nm + 520- to 650-nm light. Thus, spectral discrimination and vertical stripe fixation appear to be two distinct visual behaviors, controlled by outputs from two classes of photoreceptors and a single class of photoreceptors, respectively, and may be used in different physiological or ecological contexts. 相似文献
6.
A new genus and species of microsporidia, Andreanna caspii n. gen., n. sp. is described from the mosquito, Ochlerotatus caspius (Pallas) based on ultrastructural morphology, developmental characteristics, and comparative sequence analyses of the small subunit (SSU) ribosomal DNA (rDNA). Parasite development is confined to fat body tissue and infected larvae appear swollen with dull white masses within the thorax and abdomen. Meronts have diplokaryotic nuclei and are delineated by a simple plasmalemma contiguous with the host cell cytoplasm. Merogony occurs by synchronous binary division followed by cytokinesis. Diplokaryotic sporonts undergo meiosis and synchronous nuclear division forming sporogonial plasmodia with two, four and eight nuclei enclosed within a persistent sporophorous vesicle. Cytokinesis of sporogonial plasmodia results in the formation of eight uninucleate spores. The episporontal space of early sporonts is filled with a homogeneous accumulation of electron dense granular inclusions and ovoid vesicles of various dimensions, transforming into an interwoven matrix during the initial phase of sporogenesis. Spores are oval, uninucleate and measure 4.8 ± 0.3 × 3.1 ± 0.4 μm (fixed). The spore wall is 260 μm thick with an irregular exospore consisting of two layers (150-170 μm) and a thinner endospore (90-100 μm). The anchoring disk is well developed and is contiguous with a lamellar polaroplast that occupies the anterior third of the spore and possess more narrow lamellae on the posterior end. The polar filament is gradually tapered and arranged in a single row consisting of six coils ranging from 180 to 150 μm in diameter. The posterior vacuole (posterosome) is moderately sized and filled with a matrix of moderate electron density. Phylogenetic analysis of SSU rDNA from A. caspii and 30 other species of microsporidia including 11 genera parasitic in mosquitoes using maximum parsimony, neighbor joining and maximum likelihood methods showed A. caspii to be a sister group to the clade containing all of the Amblyospora species, including Culicospora, Edhazardia and Intrapredatorus, as well as Culicosporella and Hyalinocysta thus providing strong support for establishment of Andreanna as a separate genus. 相似文献
7.
Umbers KD 《Journal of insect physiology》2011,57(9):1198-1204
Rapid, reversible colour change is unusual in animals, but is a feature of male chameleon grasshoppers (Kosciuscola tristis). Understanding what triggers this colour change is paramount to developing hypotheses explaining its evolutionary significance. In a series of manipulative experiments the author quantified the effects of temperature, and time of day, as well as internal body temperature, on the colour of male K. tristis. The results suggest that male chameleon grasshoppers change colour primarily in response to temperature and that the rate of colour change varies considerably, with the change from black to turquoise occurring up to 10 times faster than the reverse. Body temperature changed quickly (within 10 min) in response to changes in ambient temperature, but colour change did not match this speed and thus colour is decoupled from internal temperature. This indicates that male colour change is driven primarily by ambient temperature but that their colour does not necessarily reflect current internal temperature. I propose several functional hypotheses for male colour change in K. tristis. 相似文献
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Hylis M Pilarska DK Oborník M Vávra J Solter LF Weiser J Linde A McManus ML 《Journal of invertebrate pathology》2006,91(2):105-114
A new microsporidian parasite Nosema chrysorrhoeae n. sp., isolated in Bulgaria from the browntail moth (Euproctis chrysorrhoea L.), is described. Its life cycle includes two sequential developmental cycles that are similar to the general developmental cycles of the Nosema-like microsporidia and are indistinguishable from those of two Nosema spp. from Lymantria dispar. The primary cycle takes place in the midgut tissues and produces binucleate primary spores. The secondary developmental cycle takes place exclusively in the silk glands and produces binucleate environmental spores. N. chrysorrhoeae is specific to the browntail moth. Phylogenetic analysis based on the ssu rRNA gene sequence places N. chrysorrhoeae in the Nosema/Vairimorpha clade, with the microsporidia from lymantriid and hymenopteran hosts. Partial sequences of the lsu rRNA gene and ITS of related species Nosema kovacevici (Purrini K., Weiser J., 1975. Natürliche Feinde des Goldafters, Euproctis chrysorrhoea L., im Gebiet von Kosovo, FSR Jugoslawien. Anzeiger fuer Sch?dlingskunde, Pflanzen-Umweltschutz, 48, 11-12), Nosema serbica Weiser, 1963 and Nosema sp. from Lymantria monacha was obtained and compared with N. chrysorrhoeae. The molecular data indicate the necessity of future taxonomic reevaluation of the genera Nosema and Vairimorpha. 相似文献
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Chih-Yuan Wang Wei-Fong Huang Chu-Fang Lo Chung-Hsiung Wang 《Journal of invertebrate pathology》2009,100(2):68-78
A new microsporidium was isolated from Ocinara lida Moore (Lepidoptera: Bombycidae), a pest of Ficus microcarpa L. f. in Taiwan. The microsporidium produces systemic infections in O. lida larvae; the midgut epithelium, Malpighian tubules, and midgut muscle tissues were the target tissues for this isolate, and atrophied fat body tissues were found in heavily infected larvae. Two types of spores were observed, diplokaroytic spores with 11-13 coils of polar tube, and monokaryotic spores with 12 coils of the polar tube that developed within a sporophorous vesicle to form octospores. Electron-dense granules were abundant in the episporontal space of the sporophorous vesicles, and were similar to those of Vairimorpha invictae isolated from Solenopsis invicta, but different from granules or inclusions of other Vairimorpha species. Based on the phylogenetic analysis of the small subunit ribosomal DNA sequence, this isolate is unique within the Vairimorpha complex. Morphological and genetic characters showed this isolate to be a new species. It is placed in the genus Vairimorpha and is described as Vairimorpha ocinarae n. sp. 相似文献
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Lucie Lantová Milena Svobodová Edgar Rowton Petr Volf 《Journal of invertebrate pathology》2010,105(2):182-189
Two new gregarines in the recently erected genus Psychodiella (formerly Ascogregarina), Psychodiella sergenti n. sp. and Psychodiella tobbi n. sp., are described based on morphology and life cycle observations conducted on larvae and adults of their natural hosts, the sand flies Phlebotomus sergenti and Phlebotomus tobbi, respectively. The phylogenetic analyses inferred from small subunit ribosomal DNA (SSU rDNA) sequences indicate the monophyly of newly described species with Psychodiella chagasi. Ps. sergenti n. sp. and Ps. tobbi n. sp. significantly differ from each other in the life cycle and in the size of life stages. The sexual development of Ps. sergenti n. sp. (syzygy, formation of gametocysts and oocysts) takes place exclusively in blood-fed Ph. sergenti females, while the sexual development of Ps. tobbi n. sp. takes place also in males and unfed females of Ph. tobbi. The susceptibility of Phlebotomus perniciosus, Phlebotomus papatasi, Ph. sergenti, Ph. tobbi, and Phlebotomus arabicus to both gregarines was examined by exposing 1st instar larvae to parasite oocysts. High host specificity was observed, as both gregarines were able to fully develop and complete regularly the life cycle only in their natural hosts. Both gregarines are considered as serious pathogens in laboratory-reared colonies of Old World sand flies. 相似文献
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The microsporidium Heterovesicula cowani, discovered in 1985, was initially identified as Vairimorpha sp. because it produces two types of spores: Nosema-like diplokaryotic spores and Thelohania-like mononuclear meiospores. However, light and electron microscopy studies revealed characters that did not fit any known microsporidian genera, and a new monotypic genus Heterovesicula was erected. The goal of this study was to test the validity of the genus Heterovesicula by molecular characterization of H. cowani and to assess its phylogenetic relationships to other microsporidia from insects. DNA from spores stored at −32 °C since 1992 was isolated and PCR-amplified with V1-1492 primers to obtain a partial small subunit ribosomal RNA gene sequence of 1165 bp, which was submitted to GenBank (Accession No. EU275200). Neighbor joining, maximum parsimony and maximum likelihood analyses performed against 18 microsporidia sequences, placed H. cowani as a sister taxon to the Nosema–Vairimorpha clade. The consensus of these analyses suggests that the Heterovesicula–Nosema–Vairimorpha group forms a dichotomy with the Encephalitozoon spp. branch. Other microsporidia parasitizing Orthoptera fell into two unrelated (or distantly related) lineages of terrestrial microsporidia: the Liebermannia spp. branch forms a dichotomy with Orthosomella operophterae within the Endoreticulatus–Orthosomella–Liebermannia group; and the Paranosema spp. branch clusters together with the Tubulinosema–Systenostrema lineage. The minimum pairwise distance in Kimura-2-Parameter analysis among 18 analyzed sequences was 0.37, which supports well the generic status for Heterovesicula. The obtained phylogenetic trees suggest that H. cowani is related to the Vairimorpha necatrix group, but not to other insect microsporidia producing octospores. 相似文献
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Philippe Borsa Jean-Dominique Durand Kang-Ning Shen Irma S. Arlyza Dedy D. Solihin Patrick Berrebi 《Comptes rendus biologies》2013,336(2):82-92
It has been previously established that the Leopard Whipray, Himantura leoparda, consists of two genetically isolated, cryptic species, provisionally designated as ‘Cluster 1’ and ‘Cluster 4’ (Arlyza et al., Mol. Phylogenet. Evol. 65 (2013) [1]). Here, we show that the two cryptic species differ by the spotting patterns on the dorsal surface of adults: Cluster-4 individuals tend to have larger-ocellated spots, which also more often have a continuous contour than Cluster-1 individuals. We show that H. leoparda's holotype has the typical larger-ocellated spot pattern, designating Cluster 4 as the actual H. leoparda. The other species (Cluster 1) is described as Himantura tutul sp. nov. on the basis of the nucleotide sequence of a 655-base pair fragment of its cytochrome-oxidase I gene (GenBank accession No. JX263335). Nucleotide synapomorphies at this locus clearly distinguish H. tutul sp. nov. from all three other valid species in the H. uarnak species complex, namely H. leoparda, H. uarnak, and H. undulata. H. tutul sp. nov. has a wide distribution in the Indo-West Pacific, from the shores of eastern Africa to the Indo-Malay archipelago. H. leoparda under its new definition has a similarly wide Indo-West Pacific distribution. 相似文献
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Criconemella anastomoides, described and illustrated herein, is characterized by the presence of regular anastomosis on the body, two zig zag lateral lines, stylet knobs sloping posteriorly, short stylet, and short body length. 相似文献
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Katherine Taylor 《Mycological Research》2009,113(3):337-353
Eucalyptus gomphocephala (tuart) is a tree native to the southwest coast of Western Australia, where, in some areas, there is a significant decline in the health of tuart. Botryosphaeriaceous taxa have been isolated as endophytes and canker pathogens from numerous hosts in many parts of the world and have been implicated in the decline of E. gomphocephala. In the present study, endophytic fungi were isolated from a wide variety of native woody plant species (Acacia cochlearis, A. rostellifera, Allocasuarina fraseriana, Agonis flexuosa, Banksia grandis, E. gomphocephala, E. marginata and Santalum acuminatum), at two locations in native E. gomphocephala woodland; a site in decline at Yalgorup National Park and a healthy site at Woodman Point Regional Park. Of the 226 isolates obtained, 154 were botryosphaeriaceous taxa, 80 % of which were found to be Neofusicoccum australe, isolated from all hosts at both collection sites. Four new species are described, Dothiorella moneti, Dothiorella santali, Neofusicoccum pennatisporum, and a species belonging to a genus only recently included in the Botryosphaeriaceae, Aplosporella yalgorensis. The other species isolated were Botryosphaeria dothidea on the new hosts A. rostellifera, A. cochlearis and E. marginata and Dichomera eucalypti, on the new host E. marginata. None of the new species formed lesions on excised stems of their host species, E. gomphocephala, or a common plantation species, E. globulus. However, Neofusicoccum australe formed lesions on excised stems of E. globulus and E. gomphocephala. 相似文献
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We report an additional case of long-term persistence of Paranosema locustae in grasshoppers of Argentina. The pathogen was introduced from North America on rangeland at Loncopué, Neuquén province. Microsporidia were not detected in pre-introduction samples whereas infected grasshoppers were found 11 years after introduction. Affected grasshoppers were the melanoplines Dichroplus elongatus, Dichroplus maculipennis, and Scotussa lemniscata, some of them with high spore loads. The case highlights the ability of P. locustae to recycle in local grasshopper communities by parasitizing susceptible species other than the natural hosts. 相似文献
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E. C. Bernard 《Journal of nematology》2005,37(1):115-120
Filenchus flagellicaudatus n. sp. and Lelenchus schmitti n. sp. are described from Pepe''opae bog on Molokai, Hawaii. Filenchus flagellicaudatus n. sp. is distinguished from all other Filenchus spp. by stylet length (10 µm), robust metacorpus, elongated basal bulb, and extraordinarily long, whip-like tail (c = 2.6, c'' = 31.8). Lelenchus schmitti n. sp. differs from other Lelenchus spp. by its shorter body length, weak dorso-ventral compression of the head region, and a more posterior vulva (V = 49-52). The spacious amphid pocket is introduced as a useful character for the differentiation of Lelenchus spp. from other Tylenchidae. 相似文献
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Factors that directly impact horizontal transmission of the microsporidium Amblyospora albifasciati to its intermediate copepod host, Mesocyclops annulatus were examined in laboratory bioassays. Results were evaluated in relation to life history strategies that facilitate persistence of the parasite in natural populations of its definitive mosquito host, Ochlerotatusalbifasciatus. A moderately high quantity of meiospores from mosquito larvae was required to infect adult female copepods; the IC50 was estimated at 3.6 × 104 meiospores/ml. Meiospore infectivity following storage at 25 °C was detected up to 30 days, while meiospores stored at 4 °C remained infectious to copepods for 17 months with virtually no decline in infectivity. Uninfected female M. annulatus are long-lived; no appreciable mortality was observed in field-collected individuals for 26 days, with a few individuals surviving up to 70 days. The pathological impact of A. albifasciati infection on M. annulatus resulted in a 30% reduction in survivorship after 7 days followed by gradual progressive mortality with no infected individuals surviving more than 40 days. This moderate level of pathogenicity allows for a steady continual release of spores into the environment where they may be ingested by mosquito larvae. Infected female copepods survived in sediment under conditions of desiccation up to 30 days, thus demonstrating their capacity to function as a link for maintaining A. albifasciati between mosquito generations following periods of desiccation. The susceptibility of late stage copepodid M. annulatus to meiospores of A. albifasciati and subsequent transstadial transmission of infection to adult females was established. 相似文献