997 resultados para Genera Planctomyces


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A distinct type of cellular organization was found in two species of the planctomycete genus Pirellula, Pirellula marina and Pirellula staleyi. Both species possess two distinct regions within the cell which are separated by a single membrane. The major region of the cell, the pirellulosome, contains the fibrillar condensed nucleoid. The other area, the polar cap region, forms a continuous layer surrounding the entire pirellulosome and displays a cap of asymmetrically distributed material at one cell pole. Immuno- and cytochemical-labelling of P. marina demonstrated that DNA is located exclusively within the pirellulosome; cell RNA is concentrated in the pirellulosome, with some RNA also located in the polar cap region.

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The organisation of cells of the planctomycete species Pirellula marina, Isosphaera pallida, Gemmata obscuriglobus, Planctomyces mat-is and Candidatus Brocadia anammoxidans was investigated based on ultrastructure derived from thin-sections of cryosubstituted cells, freeze-fracture replicas, and in the case of Gemmata obscuriglobus and Pirellllla marina, computer-aided 3-D reconstructions from serial sections of cryosubstituted cells. All planctomycete cells display a peripheral ribosome-free region, termed here the paryphoplasm, surrounding the perimeter of the cell, and an interior region including any nucleoid regions as well as ribosome-like particles, bounded by a single intracytoplasmic membrane (ICM), and termed the pirellulosome in Pirellula species. Immunogold labelling and RNase-gold cytochemistry indicates that in planctomycetes all the cell DNA is contained wholly within the interior region bounded by the ICM, and the paryphoplasm contains no DNA but at least some of the cell's RNA. The ICM in Isosphaera pallida and Planctomyces mat-is is invaginated such that the paryphoplasm forms a major portion of the cell interior in sections, but in other planctomycetes it remains as a peripheral zone. In the anaerobic ammonium-oxidising (anammox process) chemoautotroph Candidatus Brocadia anammoxidans the interior region bounded by ICM contains a further internal single-membrane-bounded region, the anam-moxosome. In Gemmata obscuriglobus. the interior ICM-bounded region contains the nuclear body, a double-membrane-bounded region containing the cell's nucleoid and all genomic DNA in addition to some RNA. Shared features of cell compartmentalisation in different planctomycetes are consistent with the monophyletic nature of the planctomycetes as a distinct division of the Bacteria. The shared organisational plan for the planctomycete cell constitutes a new type not known in cells of other bacteria.

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New cultured strains of the planctomycete division (order Planctomycetales) of the domain Bacteria related to species in the genera Gemmata and Isosphaera were isolated from soil, freshwater, and a laboratory ampicillin solution. Phylogenetic analysis of the 16S rRNA gene from eight representative isolates showed that all the isolates were members of the planctomycete division. Six isolates clustered with Gemmata obscuriglobus and related strains, while two isolates clustered with Isosphaera pallida. A double-membrane-bounded nucleoid was observed in Gemmata-related isolates but not in Isosphaera-related isolates, consistent with the ultrastructures of existing species of each genus. Two isolates from this study represent the first planctomycetes successfully cultivated from soil.

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Currently, the identification of pollinators is a critical necessity of conservation programs. After it was found that features extracted from patterns of wing venation are sufficient to discriminate among insect species, various studies have focused on this structure. We examined wing venation patterns of males and workers of five stingless bee species in order to determine if there are differences between sexes and if these differences are greater within than between species. Geometric morphometric analyses were made of the forewings of males and workers of Nannotrigona testaceicornis, Melipona quadrifasciata, Frieseomelitta varia, and Scaptotrigona aff. depilis and Plebeia remota. The patterns of males and workers from the same species were more similar than the patterns of individuals of the same sex from different species, and the patterns of both males and workers, when analyzed alone, were sufficiently different to distinguish among these five species. This demonstrates that we can use this kind of analysis for the identification of stingless bee species and that the sex of the individual does not impede identification. Computer-assisted morphometric analysis of bee wing images can be a useful tool for biodiversity studies and conservation programs.

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A new genus and new species of the mite family Eriophyidae (Phyllocoptinae), namely Cothrix erugata n. sp. et n. gen., is described from Heliconia stricta Huber (Heliconiaceae). In addition, one new genus and two new species of Diptilomiopidae, namely Rhyncadicrus asperulus n. sp. et n. gen. from banana, Musa acuminata Colla x Musa balbisiana Colla (genomic group AAB) (Musaceae) and Catarhinus granatus n. sp. from Heliconia bihai L., are described and illustrated. The mites were collected in the State of Pernambuco, Northeastern Brazil. All were vagrants on the lower leaf surfaces of their host plants and no visible damage symptoms were observed.

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Two new genera and four new species of monorchiid digeneans are described from the Great Barrier Reef and Moreton Bay, Queensland. Provitellus turrum n. g., n. sp. from Pseudocaranx dentex and Trachinotus coppingeri is characterised by the presence of vitelline follicles in the forebody, a single testis, a unipartite terminal organ and filamented eggs. Ovipusillus mayu n. g., n. sp. from Gnathanodon speciosus is characterised by the presence of two testes, vitelline follicles overlapping the ventral sucker and a large, complex cirrus-sac that contains a coiled eversible ejaculatory duct joined by the pars prostatica halfway along its length. Paramonorcheides pseudocaranxi n. sp. from Pseudocaranx dentex differs from other species described in this genus in the longer flatter forebody, entire ovary and the well-developed cirrus-sac. Chrisomon gaigai n. sp. from Trachinotus coppingeri and T botla is characterised by the unflattened forebody and transversely oval pharynx. Chrisomon is redefined to include species of Lasiotocus with a vitellarium composed of clusters of tubular acini, creating the following new combinations: C. albulae n. comb. for L. albulae Overstreet, 1969, C. ulua n. comb, for L. ulua Yamaguti, 1970 and C. weke n. comb, for L. weke Yamaguti, 1970. The diagnosis of Lasiotocus is amended accordingly and the new combinations, L. polynemi n. comb. and L. sunderbanensis n. comb., are created for C.polynemi Dutta, Hafeezullah & Manna, 1994 and C. sunderbanensis Dutta, Hafeezullah B Manna, 1994, respectively. Extrapolation of our collection data suggests that there may be as many as 80 species of monorchiids infecting carangid fishes in Australia and 180 species infecting carangids in all oceans of the world. The latter figure greatly exceeds the number of monorchiids described from all host families to date.

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A diagnosis is given for the lecithasterid genus Hysterolecithoides Yamaguti, 1934, which is now found to have two to six (possibly seven) vitelline masses. The species H. frontilatus (Manter, 1969) is returned to the genus, having been considered a member of the bunocotylid genus Neotheletrum by recent authors. It is redescribed from Siganus nebulosus, Moreton Bay, and S. doliatus, Lizard Island, Great Barrier Reef and New Caledonia, with emphasis on the presence of Juel's organ, a uterine seminal receptacle and the blind sac associated with the genital atrium. It differs from its congeners in the trajectory of the pars prostatica which recurves dorsally to the sinus-sac. Oligolecithoides Shen, 1982 is synonymised with Hysterolecithoides and O. trilobatus Shen, 1982 is synomised with H. epinepheli Yamaguti, 1934. Machidatrema Leon-Regagnon, 1998 is diagnosed, and found to be close to Hysterolecithoides, but differs in the lack of a blind-sac projecting from the dorsal genital atrium, by its tandem testes, the coiling of the uterus between the testes and the ovary, and the ventral excretory pore. M. leonae n. sp. is described from Siganus fuscescens, S. lineatus, S. doliatus, S. corallinus, S. vulpinus and Scarus globiceps at Heron Island, Queensland. It differs from its closest congener, M. akeh, in the muscular and tegumental flap over the genital pore and details of the terminal genitalia. M. chilostoma (Machida, 1980) and M. kyphosi (Yamaguti, 1970) are redescribed from Kyphosus vaigiensis from Heron Island. Neotheletrum Gibson & Bray, 1979 is diagnosed: it differs from Hysterolecithoides in its confluent excretory arms, blind seminal receptacle (no Juel's organ) and uniformly tripartite vitellarium. A cladistic analysis suggests that M. chilostoma and M. kyphosi are not best accommodated in Machidatrema, that Machidatrema (sensu stricto) is monophyletic and that Hysterolecithoides is paraphyletic. Hysterolecithoides and Machidatrema are considered hysterolecithine lecithasterids, whilst Neotheletrum is retained as an opisthadenine bunocotylid.

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The circumscription of Oxylobium and related genera has been problematic for nearly 200 years. Traditional definitions of genera in the group have relied on morphological features of the leaves, flower, and fruit that overlap extensively between genera. Therefore sequences of cpDNA (trnL-F intron and spacer) and nrDNA (ITS) were used to estimate the phylogeny of the group in an attempt to redefine the genera as monophyletic groups. Oxylobium sens. str. was found to be a well supported clade in both data sets, with the inclusion of Mirbelia oxylobioides. No other genus in the group was supported by these data, except Gastrolobium sens. lat. Some species groups within Chorizema, Mirbelia, and Podolobium were supported but relationships among these, Oxylobium and Gastrolobium differed significantly between the chloroplast and nuclear data sets. No group supported by the molecular data had a morphological synapomorphy, not even Oxylobium or Gastrolobium. Therefore it may be necessary to adopt a much broader generic concept in this group than has been done previously. Incongruence between the two molecular data sets, and very short internal basal branches in both, suggest a rapid early radiation in this group, possibly combined with hybridization and lineage sorting.

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Gasteruptiinae is the largest Gasteruptiidae subfamily, with circa 400 species that have been grouped into the worldwide Gasteruption Latreille. Based on a cladistic analysis with 43 morphological characters, 40 ingroup taxa representing all biogeographic regions, and seven outgroups (four Hyptiogastrinae, two Aulacidae and one Evaniidae), I confirm the monophyly of Gasteruptiinae and Gasteruption and recognize three exclusively Neotropical small genera: Plutofoenus Kieffer (revalidated) (southern South America), Spinolafoenus Macedo n. gen. (Chile) and Trilobitofoenus Macedo n. gen. (Central and South America). Gasteruption, supported by four synapomorphies, remains the most speciose genus in the subfamily. The four Gasteruptiinae genera are keyed and described. Seven species are keyed and described or redescribed: Plutofoenus chaeturus (Schletterer) n. comb., P. edwardsi Turner, P. paraguayensis (Schrottky), Spinolafoenus ruficornis (Spinola) n. comb., Trilobitofoenus alvarengai Macedo n. sp., T. plaumanni Macedo n. sp. and T. sericeus (Cameron) n. comb. (lectotype designated).

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Stibadocerina Alexander, a monotypic genus, includes the only known Neotropical species of the family Cylindrotomidae, S. chilensis Alexander, 1929, from South Central Chile (ca. 36 degrees 50`S-42 degrees 17`S). In this paper, Stibadocerina chilensis is redescribed and illustrated in detail. A study of wing-vein homology in the subfamily Stibadocerinae is provided, to identify the components of the reduced radial sector in Stibadocerina and related taxa. The proposed hypotheses of wing-vein homology are tested, and the systematic position of Stibadocerina is assessed through a cladistic analysis of 13 characters of the male imago, scored for exemplar species of the four genera included in the Stibadocerinae. A single most parsimonious tree supports the monophyly of the Stibadocerinae and the following relationships among its included genera: Stibadocerodes [Stibadocera (Stibadocerella + Stibadocerina)]. The subfamily includes one example of a vicariant distribution with a sister-group relationship between South Central Chilean and East Asian taxa, and supports a biogeographical interpretation of an ancestral trans-Pacific biota.

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The endemic Neotropical long-horned caddisfly subgenus Notalina (Neonotalina) Holzenthal contains nine described species, but its immature stages are unknown. In this paper the larvae and pupae of Notalina morsei Holzenthal 1986 from southeastern Brazil are described and illustrated. Larvae of the subgenus are easily recognized from other Neotropical leptocerids by the following characters: ventral apotome which is broad anteriorly and narrow posteriorly; the metanotum with three sclerites; the metasternum bearing 10-12 setae; the gill arrangement, usually including ventral and dorsal filaments from abdominal segments II to VI; and abdominal tergite IX with 6 long and 4 short setae. An updated key to known larvae of Neotropical Leptoceridae genera is provided.

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The status of all of the putative member genera of the subfamily Aephnidiogeninae is reconsidered, based mainly on the morphology of the terminal genitalia, Aephnidiogenes Nicoll, 1915 is the only genus retained in the Aaephnidiogeninae. Aephnidiogenes major Yamaguti, 1934 from Diagramma labiosum from the southern Great Barrier Reef is redescribed with particular reference to the terminal genitalia, and is shown to lack a true cirrussac, a condition considered to be diagnostic of the Aephnidiogeninae. Holorchis Stossich, 1901 is placed in the subfamily Lepidapedinae. Holorchis pycnoporus Stossich, 1901 from Pagellus acarne from off Spanish Sahara and from Diplodus vulgaris from off Italy and H. legendrei Dollfus, 1946 from Sparodon durbanensis and D. sargus from off eastern Cape Province, South Africa and from Pagellus erythrinus from the Adriatic Sea and Italy are studied and illustrated. The terminal genitalia of H. pycnoporus are found to be enigmatic, but those of H. legendrei are found to fit clearly into the 'Lepidapedon-like' pattern. A new genus Austroholorchis is erected in the Lepidapedinae, with A. sprenti (Gibson, 1987) n. comb. as the type-species. Its diagnostic features are its ani, infundibuliform oral sucker and the position of the ovary at about mid-level of the uterus. A. sprenti is illustrated, its hosts in Queensland waters being Sillago maculata, S, analis and S. ciliata. A, levis n. sp. is described from Sillago bassensis from south-western Western Australia. The genus Pseudaephnidiogenes Yamaguti, 1971 is placed in the Lepidapedinae. P. rhabdosargi (Prudhoe, 1956) from Rhabdosargus sarba from off Natal, South Africa is illustrated and the terminal genitalia of P. rhabdosargi from R. sarba and from R. holubi from off eastern Cape Province and Pseudaephnidiogenes vossi Bray, 1985 from Caffrogobius nudiceps from off eastern Cape Province, South Africa are illustrated. The genus Pseudoholorchis Yamaguti, 1958 is placed in the subfamily Lepocreadiinae. The terminal genitalia of P. pulcher (Manter, 1954) from Latridopsis ciliaris from New Zealand are illustrated, The genus Neolepocreadium Thomas, 1960 is placed in the Lepocreadiidae.

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The following lepocreadiid species are described from Cheilodactylidae from south-western Australia. Cliveus peroni n. g., n. sp, from Nemadactylus valenciennesi is characterised by its attenuated forebody and C. acaenodera n. sp. from Dactylophora nigricans by its attenuated forebody, the pattern of forebody spination and the large cirrus-sac. Jericho chojeri n. g., n. sp. from N. valenciennesi has a large infundibuliform oral sucker and paired ani. Rugocavum n. g. is distinguished by the possession of a blind, wrinkled glandular pit on the postero-ventral surface of the forebody. R. nemadactyli n. sp. from N. valenciennesi has its vitelline field restricted to the hindbody, whereas in R. morwong n. sp, from N. valenciennesi the vitelline field reaches into the forebody. Paraneocreadium australiense Kruse, 1978 from N. valenciennesi is redescribed and its coiled internal seminal vesicle and lobed gonads are considered distinctive features. Scaphatrema nemadactyli (Kurochkin & Korotaeva, 1972) n. g., n. comb. from N. valenciennesi has a wrinkled, boat-shaped body, a 'Lepidapedon-like' cirrus-sac and multiple testes; it was originally placed in the genus Multitestis, but these characters suggest that a new genus should be erected for it within the subfamily Lepidapedinae.