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1.
Two new species of oribatid mites of the genus Lasiobelba (Oribatida, Oppiidae), Lasiobelba (Lasiobelba) daamsae sp. n. and Lasiobelba (Antennoppia) nepalica sp. n., are described from eastern Nepal. Lasiobelba (L.) daamsae sp. n. is most similar to L. (L.) remota Aoki, 1959 and L. (L.) gibbosa (Mahunka, 1985), however, it differs from both by the anterior part of pedotecta I specifically curved, rostrum pointed and exobothridial setae not shorter than bothridial setae. Lasiobelba (Antennoppia) nepalica sp. n. is most similar to L. (A.) granulata (Mahunka, 1986), however, it differs from the latter by the larger body size, exobothridial setae longer than rostral setae and bothridial setae not longer than interlamellar setae. An identification key to known species of Lasiobelba is given.  相似文献   

2.
Aspergilli express fusion proteins of an animal haem peroxidase domain with fatty acid dioxygenase (DOX) activity (∼ 600 amino acids) and a functional or non-functional hydroperoxide isomerase/cytochrome P450 domain (∼ 500 amino acids with EXXR and GPHXCLG motifs). 5,8-Linoleate diol synthases (LDS; ppoA) and 10R-DOX (ppoC) of Aspergillusnidulans and A. fumigatus belong to this group. Our objective was to determine the oxylipins formed from linoleic acid by A. clavatus and their mechanism of biosynthesis. A. clavatus oxidized linoleic acid to (8R)-hydroperoxylinoleic acid (8R-HPODE), (10R)-hydroperoxy-8(E),12(Z)-octadecadienoic acid (10R-HPODE), and to (5S,8R)-dihydroxy- and (8R,11S)-dihydroxylinoleic acids (DiHODE) as major products. This occurred by abstraction of the pro-S hydrogen at C-8 and antarafacial dioxygenation at C-8 or at C-10 with double bond migration. 8R-HPODE was then isomerized to 5S,8R-DiHODE and to 8R,11S-DiHODE by abstraction of the pro-S hydrogens at C-5 and C-11 of 8R-HPODE, respectively, followed by suprafacial oxygenation. The genome of A. clavatus codes for two enzymes, which can be aligned with > 65% amino acid identity to 10R-DOX and 5,8-LDS, respectively. The 5,8-LDS homologue likely forms and isomerizes 8R-HPODE to 5S,8R-DiHODE. A third gene (ppoB) codes for a protein which carries a serine residue at the cysteine position of the P450 motif. This Cys to Ser replacement is known to abolish P450 2B4 catalysis and the hydroperoxide isomerase activity of 5,8-LDS, suggesting that ppoB of A. clavatus may not be involved in the biosynthesis of 8R,11S-DiHODE.  相似文献   

3.
The main aim of the survey was to describe the diversity and richness of Chilopoda in the selected area of the Bug River valley. The study sites were located in two regions differing in the shape of the valley, the presence of thermophilous habitats and the size of riparian forests. Pitfall traps were used as a sampling method. As a result, 444 specimens belonging to 12 centipede species of two orders – Geophilomorpha (four species) and Lithobiomorpha (eight species) were caught. Lithobius (Monotarsobius) curtipes C.L.Koch, 1847, Pachymerium ferrugineum (C.L.Koch, 1835), Lamyctes (Lamyctes) emarginatus (Newport, 1844) and Lithobius (Monotarsobius) dudichi Loksa, 1947 were the most common and the most numerous species. Of particular note is Lithobius dudichi found in Poland for the first time and previously known based on a single specimen. Two to 10 Chilopoda species were found in each habitat under investigation. The greatest species richness was found in thermophilous thickets (10 species), sandy grasslands (eight), xerothermic grasslands (eight) and mesic meadows (six). The fewest number of species (two) was found in rushes at oxbows and in wet meadows. We found differences in the species composition and the number of Chilopoda between the lower (102 specimens, six species) and the middle (324 specimens, 11 species) section of the river valley. Our results confirm the need to protect xerothermic habitats, unique almost throughout entire Central Europe, which due to their distribution and their small area covered are fairly easily subject to the process of destruction.  相似文献   

4.
Paridris in the New World is revised (Hymenoptera: Platygastridae). Fifteen species are described, of which 13 are new. Paridris aenea (Ashmead)(Mexico (Tamaulipas) and West Indies south to Bolivia and southern Brazil (Rio de Janeiro state)), Paridris armata Talamas, sp. n. (Venezuela), Paridris convexa Talamas, sp. n. (Costa Rica, Panama), Paridris dnophos Talamas, sp. n. (Mexico (Vera Cruz) south to Bolivia and central Brazil (Goiás)), Paridris gongylos Talamas & Masner, sp. n. (United States: Appalachian Mountains of Virginia, Tennessee, South Carolina), Paridris gorn Talamas & Masner, sp. n. (United States: Ohio south to Alabama, Georgia), Paridris invicta Talamas & Masner, sp. n. (Brazil: São Paulo), Paridris isabelicae Talamas & Masner, sp. n. (Cuba, Dominican Republic), Paridris lemete Talamas & Masner, sp. n. (Puerto Rico), Paridris minor Talamas, sp. n. (Cuba), Paridris nayakorum Talamas, sp. n. (Costa Rica), Paridris pallipes (Ashmead)(southeastern Canada, United States south to Costa Rica, also Brazil (São Paulo), Paridris psydrax Talamas & Masner, sp. n. (Argentina, Mexico, Paraguay, United States, Venezuela), Paridris saurotos Talamas, sp. n. (Jamaica), Paridris soucouyant Talamas & Masner, sp. n. (Colombia, Trinidad and Tobago, Venezuela). Paridris brevipennis Fouts, Paridris laeviceps (Ashmead), and Paridris nigricornis (Fouts) are treated as junior synonyms of Paridris pallipes; Paridris opaca is transferred to Probaryconus. Lectotypes are designated for Idris aenea Ashmead and Caloteleia aenea Ashmead.  相似文献   

5.
Ladislav Bocak 《ZooKeys》2012,(241):55-66
The Javanese fauna of the species group Cautires obsoletus is revised. Altogether, eight Javanese species were classified in the group; five of them are proposed to be junior subjective synonyms: Cautires fruhstorferi Dudkova & Bocak, 2010, a replacement name of Bulenides lineatus Pic, 1921, Cautires javanicus Bourgeois, 1883, Cautires inhumeralis (Pic, 1921), Cautires nigromaculatus (Pic, 1925), and Cautires pudicus (Kleine, 1931) (all synonymized to Cautires obsoletus Waterhouse, 1879). Three Javanese species are redescribed: Cautires apicalis (Pic, 1925), Cautires obsoletus (Waterhouse, 1878), and Cautires singularithorax (Pic, 1925). Cautires apicalis (Pic, 1925) is removed from the synonymy of Cautires corporaali (Pic, 1921) and reinstated as a valid name. Three new species are proposed: Cautires walteri sp. n., Cautires taoi sp. n., and Cautires sukosarensis sp. n. All species are keyed and principal diagnostic characters are illustrated. The distribution and relationships to Cautires fauna of other Great Sundas islands are briefly discussed.  相似文献   

6.
Hybridization is particularly likely to occur in initial and young polyploid complexes, and interspecies hybridization between diverged species usually leads to a complicated reticulate evolution. The Ranunculus cantoniensis complex and its allied species include R. chinensis (2x), R. silerifolius var. silerifolius (2x), R. cantoniensis (4x), R. trigonus (2x), R. shuichengensis (2x), R. diffusus (4x), R. repens (4x), R. vaginatus (5x) and R. sieboldii (6x, 8x). Many morphological intermediates can be found between the members of this complex, and the relationship among members is complicated. By analyzing internal transcribed spacers and nrDNA FISH (fluorescence in situ hybridization) signals, we unraveled the phylogenetic and genetic constitution of the various taxonomic units of this complex. Haplotypes were highly separated by median-joining network analysis and at least four haplogroups emerged in which there were 11 primary haplotypes; six out of ten taxa shared haplotype 1, suggesting that haplotype 1, a variation of the primary haplotype R. chinensis, served as the pivotal genome in the complex. The pollen characteristics and electrophoretic patterns of R. vaginatus (5x) showed it to be an intermediate between R. diffusus (4x) and R. sieboldii (6x). The distribution of R. vaginatus (5x) was located at the junction of the distributions of R. diffusus (4x) and R. sieboldii (6x). Ranunculus vaginatus (5x) shared haplotypes 7 and 8 with R. diffusus (4x), and haplotypes 8 and 9 with R. sieboldii (6x). This proved that R. vaginatus (5x) emerged from hybridization between R. diffusus (4x) and R. sieboldii (6x). The results of FISH also support a hybrid origin of R. vaginatus (5x). The findings of this study clearly show that there are only eight taxa in this polyploid complex including R. chinensis (2x), R. silerifolius var. silerifolius (2x), R. trigonus (2x), R. silerifolius var. dolicanthus(2x), R. cantoniensis (4x), R. diffusus (2x), R. vaginatus (5x) and R. sieboldii (6x, 8x). These taxa associated with each other by hybridizing with the pivotal genome. Ranunculus cantoniensis (4x) and R. vaginatus (5x) arose from hybridization events between diverged species in the polyploid complex, leading to a complicated reticulate evolution.  相似文献   

7.
Biological characteristics of two strains of the entomopathogenic nematode, Heterorhabditis floridensis (332 isolated in Florida and K22 isolated in Georgia) were described. The identity of the nematode’s symbiotic bacteria was elucidated and found to be Photorhabdus luminescens subsp. luminescens. Beneficial traits pertinent to biocontrol (environmental tolerance and virulence) were characterized. The range of temperature tolerance in the H. floridensis strains was broad and showed a high level of heat tolerance. The H. floridensis strains caused higher mortality or infection in G. mellonella at 30°C and 35°C compared with S. riobrave (355), a strain widely known to be heat tolerant, and the H. floridensis strains were also capable of infecting at 17°C whereas S. riobrave (355) was not. However, at higher temperatures (37°C and 39°C), though H. floridensis readily infected G. mellonella, S. riobrave strains caused higher levels of mortality. Desiccation tolerance in H. floridensis was similar to Heterorhabditis indica (Hom1) and S. riobrave (355) and superior to S. feltiae (SN). H. bacteriophora (Oswego) and S. carpocapsae (All) exhibited higher desiccation tolerance than the H. floridensis strains. The virulence of H. floridensis to four insect pests (Aethina tumida, Conotrachelus nenuphar, Diaprepes abbreviatus, and Tenebrio molitor) was determined relative to seven other nematodes: H. bacteriophora (Oswego), H. indica (Hom1), S. carpocapsae (All), S. feltiae (SN), S. glaseri (4-8 and Vs strains), and S. riobrave (355). Virulence to A. tumida was similar among the H. floridensis strains and other nematodes except S. glaseri (Vs), S. feltiae, and S. riobrave failed to cause higher mortality than the control. Only H. bacteriophora, H. indica, S. feltiae, S. riobrave, and S. glaseri (4-8) caused higher mortality than the control in C. nenuphar. All nematodes were pathogenic to D. abbreviatus though S. glaseri (4-8) and S. riobrave (355) were the most virulent. S. carpocapsae was the most virulent to T. molitor. In summary, the H. floridensis strains possess a wide niche breadth in temperature tolerance and have virulence and desiccation levels that are similar to a number of other entomopathogenic nematodes. The strains may be useful for biocontrol purposes in environments where temperature extremes occur within short durations.  相似文献   

8.
The taxonomy of the extinct European subgenus Drepanosorex (Mammalia, Soricidae) has traditionally been problematic, but it seems to comprise five valid species from the Pleistocene: Sorex (Drepanosorex) praearaneus, S. (D.) savini, S. (D.) margaritodon, S. (D.) austriacus and S. (D.) rupestris. The first record of Sorex (Drepanosorex) margaritodon in Western Europe comes from the Lower Red Unit (levels TE7–14) of Sima del Elefante (Sierra de Atapuerca, Burgos, Spain), which is dated to ca. 1.1–1.5 Ma. Detailed morphological comparisons and morphometric analyses have allowed us to assign the items from Sima del Elefante indisputably to this taxon. Sorex (D.) margaritodon is now firmly dated to the Early Pleistocene of Central Europe and the north of the Iberian Peninsula, which makes it a very useful biochronological tool in the continental context. Sorex (D.) margaritodon and S. (D.) savini could have evolved in Central Europe from the more primitive S. (D.) praearaneus, which could also be the potential ancestor of the Caucasian Sorex (D.) rupestris. Sorex (D.) margaritodon, the Drepanosorex species with the westernmost distribution in Europe, may be regarded as the most probable ancestor of S. (D.) austriacus.  相似文献   

9.
To determine selective effectiveness for specific pesticides on biological control species we evaluated the contact toxicity of 16 insecticides, 2 acaricides, 3 fungicides, and 5 biopesticides. Targeted species included 3 predatory mites (Phytoseiulus persimilis Athias-Henriot, Amblyseius swirskii Athias-Henriot, and Neoseiulus californicus McGregor), 5 hymenopteran parasitoids (Diglyphus isaea Walker, Aphidius colemani Viereck, Encarsia formosa Gahan, Eretmocerus eremicus Rose and Zolnerowich and E. mundus Mercet), and 2 hemipteran predators (Orius laevigatus Fieber and Nesidiocoris tenuis Reuter) in laboratory condition. In addition, residual toxicity was evaluated on P. persimilis, E. formosa, and O. laevigatus. For contact toxicity, five insecticides (spinetoram, spinosad, lepimectin, chlorfenapyr, and dinotefuran + spinetoram) showed high toxicity to predatory mites. Most pesticides tested were highly toxic to all hymenopteran species except for D. isaea which showed low susceptibility to 11 pesticides. Bistrifluron + flubendiamide and B. valismortis were less toxic to A. colemani, and only B. valismortis was safe to both E. mundus and E. eremicus. Insect growth regulators (methoxyfenozide and bistrifluron), chlorantraniliprole, and bistrifuron + flubendiamide were not toxic to hemipteran predators. Fungicides and biopesticides were safe to hemipteran predators except for two biopesticides (B. subtilis and P. fluorescens). Most pesticides had low residual toxicity to P. persimilis, with the exception of chlorfenapyr whose toxicity persisted over 7 days. One insecticide (cyantraniliprole), 2 acaricides (spiromesifen and fenpyroximate), 1 fungicide (metrafenone), and 4 biopesticides (B. subtilis, P. polymyxa, P. fluorescens, and B. valismortis) showed a much lower residual toxicity to E. formosa. Eight insecticides, 2 acaricides, 3 fungicides, and 5 biopesticides showed low residual toxicity to O. laevigatus.  相似文献   

10.
The mutagenicity of methyl methanesulfonate (MMS) was studied in a genetically marked two-component heterokaryon of Neurospora crassa. Types of genetic alterations detectable in this system are (I) point mutations in the ad-3A and ad-3B loci; (2) multilocus (chromosome) deletions in the ad-3 region, and (3) recessive lethal mutations in the whole genome. Study of the inactivation kinetics of the heterokaryotic and homokaryotic conidial fractions has made it possible to distinguish between nuclear and cytoplasmic inactivation.Forward mutations in the ad-3 region induced by MMS in the heterokaryotic fraction of conidia were obtained by a direct method with the following results: (I) The overall ad-3 forward mutation frequency increases in proportion to the 1.91 power of the concentration of MMS. (2) The forward mutation frequency of point mutations at the ad-3A and ad-3B loci increases in proportion to the 1.68 power of the concentration. (3) The forward mutation frequency of chromosome deletions in the ad-3 region increases more than exponentially with increasing concentrations of MMS. (4) After treatment for 300 min with 20 mM MMS, 15.5% of the ad-3 mutations are multilocus deletions. Tests for genotype and allelic complementation of the point mutations showed that (I) the ratio between ad-3B and ad-3A mutants was 1.75, (2) 52.1% of the ad-3B mutants showed allelic complementation, with 39.2% non-polarized and 12.9% polarized complementation patterns and 47.9% noncomplementing mutants, and (3) both the ratio between point mutations in the ad-3A and ad-3B loci and the spectrum of complementation patterns among the ad-3B mutants were independent of MMS concentration.  相似文献   

11.
The O. avara group of Oecetis is formally defined to include 4 described species, O. avara (Banks), O. disjuncta (Banks), O. elata Denning & Sykora, and O. metlacenis Bueno-Soria, and 15 new species. Oecetis marquesi Bueno-Soria, previously considered a member of the O. avara group, is treated as incertae sedis to species group, but is also redescribed and treated in the current work. New species described here (with their respective distributions) include: O. acciptrina (Costa Rica, Panama, Ecuador), O. agosta (Mexico), O. angularis (Guatemala to Ecuador), O. apache (SW USA), O. campana (Ecuador), O. constricta (Mexico to Ecuador, Venezuela, and Trinidad), O. houghtoni (North America), O. maritza (Costa Rica), O. mexicana (Mexico to Ecuador), O. patula (Guatemala, Nicaragua), O. protrusa (Mexico to Ecuador), O. sordida (Mexico, USA, Canada), O. tumida (Costa Rica), O. uncata (Costa Rica), and O. verrucula (Mexico to Costa Rica). A key to the species is also provided.  相似文献   

12.
Ichthyofauna of the Mozambique Seamount of the Indian Ocean, judging from the results of YugNIRO from the 1970s to the 1980s numbers about 130 species of bathyal and bathyal-pelagic fish that belong to 44 families. Most species belong to the families Macrouridae (16), Alepocephalidae (14), Ophidiidae (13), Squalidae (8), and Gempylidae (6). Among them, the greatest numbers and prospects of commercial importance, as over other seamounts, have about ten species: Centroscymnus coelolepis (Somniosidae), Etmopterus granulosus (Etmopteridae), Diastobranchus capensis and Synaphobranchus oregoni (Synaphobranchuidae), Alepocephalus australis, A. productus, and Rouleina attrita (Alepocephalidae), Cetonurus globiceps (Macrouridae), and Allocyttus verrucosus (Oreosomatidae); to the number of potential items of fishery one can also assign Hydrolagus africanus (Chimaeridae), Chlamydoselachus anguinus (Chlamydoselachidae), Apristurus indicus (Scyliorhinidae), Halosaurospis microchir (Halosauridae), Bathytyphlops marionae (Ipnopidae), Coelorhinchus acanthiger, and Coryphaenoides striatura (Macrouridae), Antimora rostrata (Moridae), Lamprogrammus niger and Selachophidium guentheri (Ophidiidae), and Holostethus atlanticus (Trachichthyidae). Pelagic deep-water fish (Gonostomatidae, Sternoptychidae, Myctophidae, etc.) apparently do not form aggregations having a commercial importance.  相似文献   

13.
New records of water mites (Acari: Hydrachnidia) from streams in South Korea are presented. Two species are described as new to science: Torrenticola neodentifera sp. n. (Torrenticolidae) and Atractides ermilovi sp. n. (Hygrobatidae). Five species are reported as first records for Korea: Wandesia (Wandesia) reducta Tuzovskij, 1987, Wandesia (Wandesia) cf. rara Tuzovskij, 1990, Sperchon (Sperchon) orientalis Tuzovskij, 1990, Feltria (Feltria) kuluensis Tuzovskij, 1988 and Atractides (Atractides) constrictus (Sokolow, 1934). The latter species is redescribed and elevated to species rank based on new material from the Russian Far East.  相似文献   

14.
Three glucosyltransferase (GTase) genes (gtfB, gtfC and gtfD) were cloned and sequenced from clinically isolated strains of Streptococcus mutans MT8148 (serotype c), MT4239 (c), MT4245 (e), MT4467 (e) and MT4251 (f), respectively. Comparison of the gtf genes revealed that interstrain difference of gtfB and gtfD was limited, while gtfC showed significant interstrain variations. Similar to gtfB and gtfD, gtfC possessed five direct repeats composed of homologous unit in the carboxyl-terminal portion. The repeating unit consisted of 63–65 amino acid residues and is responsible for glucan binding. The gtfC gene from S. mutans MT4245 lacked the fourth unit. Multiple alignment with the gtf sequence of strain GS-5 (c) revealed several changes in these gtf genes due to frameshift mutations. The peptides encoded by the gtfB, gtfC and gtfD genes of GS-5 were 1, 80, and 32 amino acid residues shorter than those of the test strains except strain MT4245.  相似文献   

15.
We carried out a quantitative assessment of the consumption of herbaceous plants by Opatrum sabulosum (Linnaeus, 1761) – a highly significant agricultural pest species. We researched the feeding preferences of this pest species with respect to 33 uncultivated and 22 cultivated plant species. This species of darkling beetle feeds on many uncultivated plant species, including those with hairy leaves and bitter milky sap, such as Scabiosa ucrainca (5.21 mg/specimen/24 hours), Euphorbia virgata (3.45), Solanum nigrum (3.32), Centauria scabiosa (2.47), Lamium album (2.41), Aristolochia clematitis (1.76), Chenopodium album (1.73), Arctium lappa (1.51), Asperula odorata (1.20). A high rate of leaf consumption is also characteristic for cultivated species, for example, Perilla nankinensis (5.05 mg/specimen/24 hours), Lycopersicon esculentum (3.75), Tropaeolum majus (3.29), Nicotiana tabacum (2.66), Rumex acetosa (1.96), Beta vulgaris (1.27). Opatrum sabulosum is capable of feeding on plants which are poisonous to cattle. This species of darkling beetle consumes 95.5% of the cultivated and 48.5% of the uncultivated herbaceous plants researched.  相似文献   

16.
Species of the shore-fly genus Gymnoclasiopa Hendel from the New World are revised, including Gymnoclasiopa grecorum sp. n. (Alaska. Juneau: Gastineau Channel, Thane Road (S Juneau; 58°16.9''N, 134°22.4''W)) and Gymnoclasiopa matanuska sp. n. (Alaska. Matanuska-Susitna: Palmer (Matanuska River; 61°36.5''N, 149°04.1''W)). We also clarify the status of previously described species, including those now discovered to have Holarctic distributions and/or for which sexual dimorphism was not appreciated and the species was described twice, including Gymnoclasiopa montana (Cresson) as a syn. n. of Gymnoclasiopa bohemanni (Becker). Two species, Gymnoclasiopa bella (Mathis), comb. n., and Gymnoclasiopa chiapas (Mathis), comb. n., are transferred from Ditrichophora to Gymnoclasiopa, and Gymnoclasiopa cana Cresson stat. rev. and Ditrichophora canifrons Cresson, stat. rev. are returned to Ditrichophora, the genus in which Cresson originally described them. A neotype is designated for Gymnoclasiopa tacoma to stabilize the nomenclature of this species. The two excluded species, Ditrichophora cana and Ditrichophora canifrons, are diagnosed and distributional data are also provided. For all known New World species of Gymnoclasiopa, structures of the male terminalia are described for the first time and are fully illustrated. Detailed locality data and distribution maps are also included. To provide context and also to facilitate identification, diagnoses are included for the tribe Discocerinini and genus in addition to a key to the genera and species occurring in the New World.  相似文献   

17.
Seven different monoclonal antibodies (MAbs) specific to only Vibrio cholerae were produced using a combination of five representative serotypes of V. cholerae for immunization. The first three MAbs (VC-93, VC-82 and VC-223) were specific to the V. cholerae serogroup O1 with different avidity for the serotypes O1 Inaba and O1 Ogawa. The fourth and the fifth MAbs were specific to V. cholerae O139 (VC-812) or O141 (VC-191) serogroups, respectively. The sixth MAb (VC-26) bound to all three serogroups of V. cholerae. The seventh MAb (VC-63) bound to all twenty five isolates of V. cholerae used in this study. None of the seven MAbs showed cross-reactivity with other Vibrio spp. or closely-related V. cholerae species, V. mimicus or other gram-negative bacteria. The eighth MAbs (VC-201) specific to almost all Vibrio spp. was also obtained. In dot blotting, these MAbs can be used to detect a diluted pure culture of V. cholerae in solution with a sensitivity range of from 105 to 107 CFU ml− 1. However, the detection capability could be improved equivalent to that of PCR technique after preincubation of samples in alkaline peptone water (APW). Thus, these MAbs constitute convenient immunological tools that can be used for simple, rapid and simultaneous direct detection and differentiation of the individual serotypes of V. cholerae in complex samples, such as food and infected animals, without the requirement for bacterial isolation or biochemical characterization.  相似文献   

18.
The genus Sathrophyllia Stål, 1874 from Pakistan is reviewed with four species recorded. The diagnostic characters are given and two new species Sathrophyllia saeedi sp. n. and Sathrophyllia irshadi sp. n. are described. In addition to that Sathrophyllia nr. rugosa (Linnaeus, 1758) and Sathrophyllia femorata (Fabricius, 1787) are re-described. Further information on the distribution and ecology of the species is given and a key to studied species of Sathrophyllia is presented. Sathrophyllia femorata (Fabricius, 1787) and Sathrophyllia rugosa (Linnaeus, 1758) are recorded from Rawalakot (KPK) and Tharparker (Sindh), Pakistan for first the time.  相似文献   

19.
The genus Hisonotus was resurrected as a member of the tribe Otothyrini (actually subfamily Otothyrinae). However, phylogenetic studies based on morphological and molecular data showed that Hisonotus is not monophyletic and independent lineages can be identified, such as the group composed of the species Hisonotus insperatus, Hisonotus luteofrenatus, Hisonotus oliveirai, Hisonotus paresi and Hisonotus piracanjuba, a lineage unrelated to that containing the type species of the genus Hisonotus (Hisonotus notatus). Herein, based in molecular and morphological data, a new genus is described to accommodate the lineage mentioned above, into which are also added three new species. This new genus can be distinguished from other genera of Otothyrinae by the following combination of characters: (1) a pair of rostral plates at the tip of the snout; (2) two large pre-nasal plates just posterior to the rostral plates; (3) a supra-opercular plate that receives the laterosensory canal from the compound pterotic before the preopercle; (4) a well developed membrane at anal opening in females; and (5) a V-shaped spinelet. A key to species of Curculionichthys is provided.  相似文献   

20.
Leukotoxin (Ltx) is a prominent virulence factor produced by Aggregatibacter actinomycetemcomitans, an oral microorganism highly associated with aggressive periodontitis. Ltx compromises host responsiveness by altering the viability of neutrophils, lymphocytes, and macrophages. Previously, we developed a Rhesus (Rh) monkey colonization model designed to determine the effect of virulence gene mutations on colonization of A. actinomycetemcomitans. Unexpectedly, an A. actinomycetemcomitans leukotoxin (ltxA) mutant (RhAa-VS2) failed to colonize in the Rh model. No previous literature suggested that Ltx was associated with A. actinomycetemcomitans binding to tooth surfaces. These results led us to explore the broad effects of the ltxA mutation in vitro. Results indicated that LtxA activity was completely abolished in RhAa-VS2 strain, while complementation significantly (P<0.0001) restored leukotoxicity compared to RhAa-VS2 strain. RT-PCR analysis of ltx gene expression ruled out polar effects. Furthermore, binding of RhAa-VS2 to salivary-coated hydroxyapatite (SHA) was significantly decreased (P<0.0001) compared to wild type RhAa3 strain. Real time RT-PCR analysis of the genes related to SHA binding in RhAa-VS2 showed that genes related to binding were downregulated [rcpA (P = 0.018), rcpB (P = 0.02), tadA (P = 0.002)] as compared to wild type RhAa3. RhAa-VS2 also exhibited decreased biofilm depth (P = 0.008) and exo-polysaccharide production (P<0.0001). Buccal epithelial cell (BEC) binding of RhAa-VS2 was unaffected. Complementation with ltxA restored binding to SHA (P<0.002) but had no effect on biofilm formation when compared to RhAa3. In conclusion, mutation of ltxA diminished hard tissue binding in vitro, which helps explain the previous in vivo failure of a ltxA knockout to colonize the Rh oral cavity. These results suggest that; 1) one specific gene knockout (in this case ltxA) could affect other seemingly unrelated genes (such as rcpA, rcpB tadA etc), and 2) some caution should be used when interpreting the effect attributed to targeted gene mutations when seen in a competitive in vivo environment.  相似文献   

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