945 resultados para Reactive species of oxygen


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Opechona austrobacillaris n, sp. is described from Pomatomus saltatrix from marine sites off Western Australia and New South Wales, Australia. It differs from O. bacillaris in its elongate outline, small ventral sucker, longer pseudoesophagus (relative to the oesophagus), relatively shorter ventral sucker to ovary distance and the relatively longer post-testicular region. Lepotrema monile n. sp. is described from Pomacentrus wardi from Heron Island, Queensland. It differs from its congeners in the sphincter around the distal metraterm and the more-or-less oval ovary. Bianium spongiosum n. sp, is described from Ostracion cubicus from Lizard Island, Queensland. It differs from its congeners in lacking lateral flaps in the forebody, but in having large, internal spongiform patches in the lateral forebody. The following species are redescribed from Australian sites: Lepocreadium oyabitcha from Abudefduf whitleyi, Lizard Island; Clavogalea trachinoti from Trachinotus botla, Heron Island and T. coppingeri, New South Wales, Stradbroke Island, Queensland and Heron Island; Myzoxenus insolens from Notolabrus parilus, Western Australia; Bulbocirrus aulostomi from Aulostomus chinensis, Heron Island; Lepocreadioides orientalis [new synonyms: Bicaudum interruptum Bilqees, 1973; Lepocreadioides interruptum (Bilqees, 1973) Madhavi, Narasimhulu & Shameem, 1986; Lepocreadioides discum Wang, 1986; Lepocreadioides sp. of Karyakarte & Yadav (1976)] from Cynoglossus bilineata, Moreton Bay, Queensland; Hypocreadium patellare from Sufflamen chrysopterus, Heron Island; Echeneidocoelium indicum from Echeneis naucrates, Heron Island; Multitestis pyriformis from Epinephelus cyanopodus, Heron Island; Pseudopisthogonoporus vitellosus from Naso brevirostris, Heron Island; and Bianium hispidum from Torquigener whitleyi and T. pleurogramma, southern Queensland. Only M. solens and M. pyriformis have been reported from Australian waters before; both are new host records.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new species of the genus Gluconacetobacter, for which the name Gluconacetobacter sacchari sp. nov. is proposed, was isolated from the leaf sheath of sugar cane and from the pink sugar-cane mealy bug, Saccharicoccus sacchari, found on sugar cane growing in Queensland and northern New South Wales, Australia, The nearest phylogenetic relatives in the alpha-subclass of the Proteobacteria are Gluconacetobacter liquefaciens and Gluconacetobacter diazotrophicus, which have 98.8-99.3% and 97.9-98.5% 16S rDNA sequence similarity, respectively, to members of Gluconacetobacter sacchari. On the basis of the phylogenetic positioning of the strains, DNA reassociation studies, phenotypic tests and the presence of the Q10 ubiquinone, this new species was assigned to the genus Gluconacetobacter. No single phenotypic characteristic is unique to the species, but the species can be differentiated phenotypically from closely related members of the acetic acid bacteria by growth in the presence of 0.01% malachite green, growth on 30% glucose, an inability to fix nitrogen and an inability to grow with the L-amino acids asparagine, glycine, glutamine, threonine and tryptophan when D-mannitol was supplied as the sole carbon and energy source. The type strain of this species is strain SRI 1794(T) (= DSM 12717(T)).

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Aponurus chelebesoi n. sp. is described from Chaetodon auriga, C. citrinellus, C. ephippium, C. flavirostris, C. lineolatus, C. melannotus, C. mertensii, C. pelewensis, C. lunulatus, C. vagabundus, Coradion altivelis, Forcipiger flavissimus, Heniochus acuminatus, H. chrysostomus and H. monoceros from the southern coast of New Caledonia. It is distinguished from most species in the genera Aponurus (synonym Brachadena) and Lecithophyllum by its claviform (as opposed to oval to subglobular) vitelline lobes. Three species, A. pyriformis, Lecithophyllum vogeae and Brachadena cheilonis, have similar claviform vitelline lobes, but differ from A. chelebesoi in their tandem testes and the distinct egg-size.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Three species of Trifoliovarium are described from marine fishes from Moreton Bay, Queensland: T. triacanthi (Parukhin, 1964) n. comb. (syns Hysterolecitha triacanthi Parukhin, 1964; T. triacanthi Bilqees, 1973; T. triacanthusi Gupta & Ahmad, 1976) from Tripodichthys angustifrons; T. ovarilobulus (Wang, 1989) n. comb. (syn. Hysterolecithia[sic]ovarilobulus) from Paramonacanthus japonicus and Pelates quadrilineatus; and T. draconis n. sp. from Callionymus sublaevis and C. belcheri. A list of the species of the subfamily Trifoliovariinae is given along with a key. A cladistic study of the subfamily based on 23 characters is presented, the results of which indicate the monophyly of the genus Assitrema and the paraphyly of Trifoliovarium.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The present paper proposes an approach to obtaining the activation energy distribution for chemisorption of oxygen onto carbon surfaces, while simultaneously allowing for the activation energy dependence of the pre-exponential factor of the rate constant. Prior studies in this area have considered this factor to be uniform, thereby biasing estimated distributions. The results show that the derived activation energy distribution is not sensitive to the chemisorption mechanism because of the step function like property of the coverage. The activation energy distribution is essentially uniform for some carbons, and has two or possibly more discrete stages, suggestive of at least two types of sites, each with its own uniform distribution. The pre-exponential factors of the reactions are determined directly from the experimental data, and are found not to be constant as assumed in earlier work, but correlated with the activation energy. The latter results empirically follow an exponential function, supporting some earlier statistical and experimental work. The activation energy distribution obtained in the present paper permits improved correlation of chemisorption data in comparison to earlier studies. (C) 2000 Elsevier Science Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Neolebouria moretonensis n. sp. is described from Gerres subfasciatus (Gerreidae) from Moreton Bay, south-east Queensland and N. lineatus n. sp. is described from Centroberyx lineatus (Berycidae) from off Rottnest Island, south-west Western Australia. C. lineatus represents a new host family and order (Beryciformes) for the genus. The two new species are distinguished within the genus by their entire, tandem to oblique testes and cirrus-sacs that do not extend into the hind-body, by being less than 1 mm in length, and by the position of the genital pore and the relative size of the forebody and post-testicular region. N. lineatus and N. moretonensis are very similar but are distinguished by their caeca which extend further posteriorly in N. moretonensis. There is no apparent pattern in the host-specificity of this genus.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

An unusual new species of the gall-inducing scale insect genus Apiomorpha Rubsaamen is described from Queensland. The adult female, its gall, and the first-instar nymph (crawler) are illustrated, and relationships of the new species are estimated using mitochondrial COII data. Adult females induce cigar-shaped galls on leaves of several eucalypts in section Adnataria of subgenus Symphyomyrtus. The bilobed anal lobes of the adult female differ from those of all other Apiomorpha species (single lobe) and the first-instar nymph possesses features, such as broad frontal tubercles and dorsal stripes, that are not present in crawlers of other Apiomorpha species. However, DNA sequence data confirm that the new species falls within Apiomorpha, rather than representing a sister group, and indicate that the new species is not closely related to the A. pharetrata (Schrader) species-group, the only other group within Apiomorpha that induces cigar-shaped galls on leaves. The systematic affiliations of A. gullanae sp. n. are currently not known. Females only are known and there is some indication that reproduction in the new taxon is parthenogenetic. This represents the first putative case of parthenogenesis in Apiomorpha.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We aimed to study patterns of variation and factors influencing the evolutionary dynamics of a satellite DNA, pBuM, in all seven Drosophila species from the buzzatii cluster (repleta group). We analyzed 117 alpha pBuM-1 (monomer length 190 bp) and 119 composite alpha/beta (370 bp) pBuM-2 repeats and determined the chromosome location and long-range organization on DNA fibers of major sequence variants. Such combined methodologies in the study of satDNAs have been used in very few organisms. In most species, concerted evolution is linked to high copy number of pBuM repeats. Species presenting low-abundance and scattered distributed pBuM repeats did not undergo concerted evolution and maintained part of the ancestral inter-repeat variability. The alpha and alpha/beta repeats colocalized in heterochromatic regions and were distributed on multiple chromosomes, with notable differences between species. High-resolution FISH revealed array sizes of a few kilobases to over 0.7 Mb and mutual arrangements of alpha and alpha/beta repeats along the same DNA fibers, but with considerable changes in the amount of each variant across species. From sequence, chromosomal and phylogenetic data, we could infer that homogenization and amplification events involved both new and ancestral pBuM variants. Altogether, the data on the structure and organization of the pBuM satDNA give insights into genome evolution including mechanisms that contribute to concerted evolution and diversification.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Chetoneura shennonggongensis Amorim & Niu, sp. n., inhabiting caves in East China, is described based on the adult male and female, plus larva. Chetoneura Colless, previously associated with Orfelia and known from a single species from caves in Malaysia, is formally transferred to the Keroplatini. This is the first description of the larva and of the general biology of the genus. The larva of this new species is suspended in a roughly horizontal hammock of silken threads amidst mucous coated snare threads from the roof of caves, but is not bioluminescent as some species of other genera in Keroplatidae ( e. g., Arachnocampa, Keroplatus, and Orfelia). A key to separate both species of the genus is provided. The position of the genus within the Keroplatini is considered. Chetoneura is considered to be closely related to a clade containing Heteropterna and Ctenoceridion.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We have measured nucleotide variation in the CLOCK/CYCLE heterodimer inhibition domain (CCID) of the clock X-linked gene period in seven species belonging to the Drosophila buzzatii cluster, namely D. buzzatii, Drosophila koepferae, Drosophila antonietae, Drosophila serido, Drosophila gouveai, Drosophila seriema and Drosophila borborema. We detected that the purifying selection is the main force driving the sequence evolution in period, in agreement with the important role of CCID in clock machinery. Our survey revealed that period provides valuable phylogenetic information that allowed to resolve phylogenetic relationships among D. gouveai, D. borborema and D. seriema, which composed a polytomic clade in preliminary studies. The analysis of patterns of intraspecific variation revealed two different lineages of period in D. koepferae, probably reflecting introgressive hybridization from D. buzzatii, in concordance with previous molecular data.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Paratrizygia Tonnoir was originally described for P. conformis, from Australia, and since then only four species have been added to the genus, from Chile and Southern Argentina. We add four new species to the genus Paratrizygia-P. balbii sp. nov., P. alvesi sp. nov., P. camargoi sp. nov., and P. albidens sp.nov.-from the southern part of the Brazilian Atlantic Forest. Comments are made about the possible relationships of the Brazilian and other Neotropical species of the genus. An identification key to the Neotropical species of the genus is provided.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A second species of the genus Eratomyia Amorim & Rindal-E. risaralda, sp. n.-is described from Risaralda, Colombia, based on one male and three females. The female of Eratomyia is described for the first time. A number of striking modifications in the female terminalia shared with Chiletricha Chandler support the hypothesis that they are sister genera within the Rangomaramidae. The position of Chiletricha and Eratomyia within the Chiletrichinae is discussed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Five New World species of Chrysotus Meigen are redescribed, four of them herein transferred from Diaphorus Meigen: C. angustifrons (Robinson), comb.nov., C. maculatus (Parent), comb.nov. (= D. maculipennis Robinson), C. robustus(Robinson), comb. nov., C. spectabilis (Loew) and C. wirthi (Robinson), comb. nov. The female of C. maculatus is described for the first time. Terminalia of both males and females are illustrated. The previous suggestion that C. angustifrons, C. robustus, C. wirthi, and C. spectabilis and the Neotropical genus Lyroneurus Loew are closely related based on wing venation similarities is analyzed and rejected.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Drosophila antonietae and Drosophila gouveai are allopatric, cactophilic, cryptic and endemic of South America species, which aedeagus morphology is considered the main diagnostic character. In this work, single close populations from the edge distributions of each species, located in an ""introgressive corridor"", were analyzed regarding temporal isozenzymatic genetic variability. Isocitrate dehydrogenase (Idh) appeared as a diagnostic locus between D. antonieate and D. gouveai because each population was fixed for different alleles. Moreover, several polymorphic loci showed accentuated divergence in the allele frequency, as evidenced by Nei`s l(0.3188) and D (1.1432), and also by Reynolds` genetic distance and identity (1.3207 and 0.7331, respectively). Our results showed that, in spite of the very similar external morphology, related evolutionary histories, close distributions, and events of introgression in the studied area, these cryptic species have high allozymatic differentiation, and this is discussed here. (C) 2010 Elsevier Ltd. All rights reserved.