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1.
During 1988 and 1989, 409 specimens of southern African Anura, comprising 50 species in 9 families, were checked for opalinids in the cloaca. Protozelleriella devilliersi n. g., n. sp. was found in three of four Capensibufo rosei (Bufonidae); Zelleriella africana Sandon, 1938 in two of three Bufo angusticeps and one of 20 B. garmani (Bufonidae) plus three of 12 Phrynobatrachus natalensis, 12 of 19 Tomopterna cryptotis, seven of 14 T. delalandii, three of seven T. krugerensis and one of six T. natalensis (all Ranidae); Z. gambieri n. sp. in one of six T. natalensis; Z. garlandi n. sp. in two of six Kassina maculata (Hyperoliidae); Z. sandoni n. sp. in two of 20 B. garmani, two of six K. maculata, one of seven K. senegalensis and one of four Leptopelis mossambicus (Hyperoliidae) plus one of five Phrynomerus bifasciatus (Microhylidae) and two of 19 T. cryptotis. It is suggested that the Ranidae (in particular the genus Tomopterna) and the Hyperoliidae are among the major carriers of Zelleriella in the Afrotropical Region.  相似文献   

2.
During 1988 and 1989, 409 specimens of southern African Anura comprising 50 species in nine families were checked for opalinids in the cloaca. Opalina natalensis Metcalf, 1923 was found in four of 12 Phrynobatrachus natalensis (Ranidae) and O. duquesnei n. sp. in four of five Chiromantis xerampelina (Rhacophoridae). Opalina amygdala (Boisson, 1965) and O. foliacea (Boisson, 1959) are proposed as new combinations. It is suggested that the Ranidae (in particular the genera Phrynobatrachus and Ptychadena), the Hyperoliidae (in particular the genus Leptopelis) and the Rhacophoridae (with the genus Chiromantis) are among the major carriers of Opalina in the Afrotropical Region.  相似文献   

3.
During 1988 and 1989 409 specimens, representing 50 species in 9 families of southern African Anura from 26 localities throughout the Republic of South Africa and from Swaziland, were examined for gallbladder myxozoans. Myxidium lesminteri n. sp. was the only myxozoan found and was observed in one tomopterna krugerensis (Ranidae), one Bufo garmani (Bufonidae) and one Heleophryne natalensis (Heleophrynidae), all from Transvaal. The spore of Myxidium lesminteri (9.5–15.0 × 5.0–8.0 m) is characterised by a smooth shell devoid of striations but has one longitudinal ridge.  相似文献   

4.
During 1992, the cloaca of 83 specimens of North American Amphibia from Algonquin Park and Kingston, Ontario, Canada, and from El Paso County, Texas, USA, comprising 14 species in seven families, were checked for opalinids. Opalina martinonae n. sp. was found in five of nine Rana sylvatica (Ranidae); O. obtrigonoidea Metcalf, 1923 in six of 11 Bufo americanus (Bufonidae) and two of nine Pseudacris crucifer (Hylidae); O. pickeringi Metcalf, 1923 in two of nine Pseudacris crucifer and in one of six Rana pipiens; and O. virguloidea Metcalf, 1923 in two of six Hyla versicolor (Hylidae). Opalina flava Stokes, 1884 is proposed for Cepedea flava (Stokes, 1884) Metcalf, 1923. The occurrence, evolution and biogeography of North American Opalina are discussed.  相似文献   

5.
During 1988 and 1989, 409 specimens of southern African Anura comprising 50 species in nine families, were checked for opalines in the cloaca. Protoopalina africana Metcalf, 1923 was found in Rana angolensis (Ranidae); P. appendiculata Fantham, 1929 in R. fuscigula; P. boycotti n. sp. in Pyxicephalus adspersus (Ranidae); P. brevis Boisson, 1959 in Ptychadena oxyrhynchus (Ranidae); P. drachi Tuzet & Knoepffler, 1968 in Ptychadena anchietae, P. mascareniensis, P. mossambica and P. oxyrhynchus (Ranidae); P. nutti Metcalf, 1923 in Bufo rangeri (Bufonidae); P. octomixa Fantham, 1930 in Schismaderma carens (Bufonidae); P. ovalis Fantham, 1929 in Rana angolensis (Ranidae); P. pattersoni n. sp. in Ptychadena mascareniensis (Ranidae); P. petiti Tuzet & Knoepffler, 1968 in Ptychadena oxyrhynchus (Ranidae); P. primordialis (Awerinzew, 1913) Metcalf, 1918 in Bufo angusticeps, B. gariepensis, B. garmani, B. rangeri (Bufonidae), Heleophryne natalensis (juveniles and tadpoles) (Heleophrynidae), Xenopus laevis (juveniles and tadpoles) (Pipidae), Cacosternum boettgeri, Ptychadena mossambica (juvenile), Rana angolensis, R. fuscigula and Strongylopus grayii (Ranidae); P. stevensoni (Stevenson, 1911) Metcalf, 1923 in Bufo gariepensis, B. garmani, B. gutturalis, B. maculatus, B. rangeri, Capensibufo rosei (Bufonidae), Rana angolensis and R. fuscigula (Ranidae); P. transvaalensis Fantham, 1923 in Pyxicephalus adspersus (Ranidae); and P. xenopodos Metcalf, 1923 in Xenopus laevis (including tadpoles) and X. muelleri (Pipidae). It is suggested that the Bufonidae (genus Bufo) and the Ranidae (in particular the genera Cacosternum, Ptychadena, Rana and Strongylopus) are among the major carriers of Protoopalina in the Afrotropical Regional. The biogeography and evolution of the genus Protoopalina are discussed.  相似文献   

6.
Species richness and similarity in metazoan parasite communities of fishes can be influenced by several biotic (age, body size, vagility, feeding and social behavior, among others), and local abiotic (temperature, salinity, etc.) factors. The parasite communities of three species of Oligoplites, marine fishes from the Pacific coast of Mexico, were quantified and analyzed. Four hundred sixty‐eight leatherjackets (O. altus, n=94; O. saurus, n=260; and Orefulgens, n=114) were collected from February 2016 to June 2017 from five locations. Twenty‐eight species of metazoan parasites were recovered and identified: four species of Monogenea (adults), nine of Digenea (seven adults and two metacercariae); two of Cestoda (larvae); four of Nematoda (two adults and two larvae); four of Acanthocephala (two adults, one juvenile, and one cystacanth); four of Copepoda; and one Pentastomida (larvae). At the component community level, species richness ranged from 9 in O. saurus to 19 in O. altus. Different species of helminth dominated the component communities of each species of host. Community composition and species richness of parasites differed among the three species of host, locations, and sampling years. Host feeding behavior, body size, and vagility had the most influence on these differences.  相似文献   

7.
In September and October 1992, 97 Colombian amphibians collected at eight sites and comprising 25 species in eight families were checked for opalines in the cloaca. Zelleriella falcata Carini, 1933 was found in one Elachistocleis ovalis (Microhylidae); Z. microcarya Metcalf, 1923 in three of six Rana vaillanti (Ranidae); Z. stewarti n. sp. in four of seven Colostethus subpunctatus (Dendrobatidae); Z. dendrobatidis Metcalf, 1923 in one juvenile of C. palmatus; Z. antilliensis (Metcalf, 1914) in three of eight Bufo marinus (Bufonidae), one of 14 juveniles of Leptodactylus sp. (Leptodactylidae), four of five L. fuscus and one of three L. ventrimarmoratus; and Z. opisthocarya Metcalf, 1923 in one of eight B. marinus; Z. paludicolae Metcalf, 1923 in one of three L. ventrimarmoratus; Zelleriella sp. in one of six B. granulosus. Z. xyster is proposed as a new combination for Protoopalina xyster Metcalf, 1923. The occurrence, evolution and biogeography of Neotropical Zelleriella are discussed.  相似文献   

8.
Phytochemical investigation of the stem bark of Ficus natalensis afforded eleven compounds including one ceramide (1), two anthraquinones (2, 3), four triterpenes (47), two polyols (8, 9) and two steroids (10, 11). The structures of the compounds were determined by spectroscopic analyses including IR, UV, MS, 1D- and 2D- NMR (1H, 13C, 1H–1H COSY, HMQC, HMBC and NOESY), as well as by comparison with literature data. The antibacterial activity and the cytotoxicity of the extract, fractions and some isolated compounds (3, 5, 8 and 9) were evaluated. Some fractions and sub-fractions from various column chromatography displayed moderate antibacterial activity with diameter zone of inhibition (DZI) ranging from 7 to 10 mm. None of the compounds tested had activity. In the present study, all the compounds are isolated for the first time from the species F. natalensis. Compounds 2, 47, 10 and 11 were previously reported from the genus Ficus. The chemophenetic significance of the isolated compounds is discussed.  相似文献   

9.

Information on the reproductive anatomy in genera of the tribe Naucleeae, particularly Cephalanthus, is scarce and fragmented. Of the six species in the genus, only the mature megagamethophyte of Cephalanthus occidentalis has been described. This study aims to provide information on embryological aspects in flowers of C. glabratus and to analyze the morphology and anatomy of the flowers, fruit, and seed in the six species of the genus. Cephalanthus glabratus have imperfect flowers: pistillate (PF) and staminate (SF). In the PF, the ovules are functional, while in the SF, they atrophy during the formation of the embryo sac. The mature ovule has a single integument, corresponds to the Phyllis type and the embryo sac is a Polygonum type, forming only in the PF. The presence of pollenkitt and secondary presentation of pollen were observed in the SF, as well as in the pollen formation previously described, whereas in the PF, they are absent, due to the collapse of the pollen grains inside the indehiscent anthers. The analysis of the ontogeny of the ovular excrescence in C. glabratus determined its funicular origin, calling it an aril. Its development is a pre-anthesis event, initiated during megasporogenesis. In seeds, the aril is a fleshy, white appendage which almost completely envelops the seeds of Cephalanthus, except for Cephalanthus natalensis where it is noticeably more reduced. Studies of the fruit in Cephalanthus species indicate that the infructescence is a dry schizocarp which separates into uni-seminated mericarps, except in C. natalensis that has fleshy indehiscent fruit.

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10.
Among four different genera in Galaxauraceae, species diversity of the genus Tricleocarpa Huisman & Borowitzka is underestimated and requires further examination. In this study, we explored a molecular phylogeny of Tricleocarpa with an emphasis on Taiwan species and reassessed species diversity of the genus from the Indo-Pacific region based on analyses of rbcL and COI-5P sequences and morphological observations. The molecular analyses showed that species of Tricleocarpa examined are grouped into seven clades: six clades in the T. cylindrica group (the T. cylindrica complex, T. confertus, T. jejuensis, T. natalensis and two uncharacterized T. ‘cylindrica’ clades) and one clade as the T. fragilis group. Overall, at least 12 species in Tricleocarpa were detected from the Indo-Pacific region, including a new species, T. confertus S.-L. Liu & S.-M. Lin, from Taiwan. Among them, T. confertus can be separated from other species of Tricleocarpa by a thallus consisting of dichotomous or trichotomous, articulated and moniliform branches with smooth surfaces, constrictions at nodes and slightly anti-triangular in shape. The cystocarp morphology of T. confertus is similar to the T. cylindrica group by having paraphyses intermixing with gonimoblast filaments. Recognition of this new species from other species is also supported by the DNA-based, algorithmic species delimitation approaches. With the combination of molecular phylogeny and species diversity reassessment, our phylogeographic analysis supported a trend that species in the T. fragilis group are restricted in their distribution to subtropical and tropical areas whereas species in the T. cylindrica group have a wide distribution, ranging from temperate through to tropical areas.  相似文献   

11.
The close systematic affinities between the composite genera Haplopappus and Chrysothamnus, including different points of contact with “intergeneric” hybrids, are reviewed. The Mohave Desert has several shrubby representatives of each genus, and at census sites from the east-central New York Mountains to buttes at the extreme western end of the desert, north-facing granitic slopes at the foothills of mountain ranges support four Haplopappus species (H. cuneatus. H. laricifolius, H. linearifolias and H. cooperi) and one Chrysothamnus (C. teretifolius). These five species occupy “distributional niches” represented as ranges and areas of dominance on the habitat plane of slope angle and proportion of rocks in the substrate. Central desert sites have four species (excluding C. teretifolius); peripheral desert sites always include C. teretifolius rather than H. laricifolius and support two to four species depending on the size and isolation of the suitable habitat area. Species may occupy different positions on the habitat gradient depending on species number at the site, moisture availability, and in particular competition from other species. C. teretifolius appears to be favored when population turnover rates are high, either in disturbed sites or on natural islands of habitat.  相似文献   

12.
The tribe Abrotrichini (five genera and 14 living species) is a small clade within the speciose subfamily Sigmodontinae (Rodentia, Cricetidae), representing one of the extant successful radiations of mammals at southern high latitudes of the Neotropics. Its distribution is mostly Andean, reaching its greatest diversity in southern Argentina and Chile. We evaluate the phylogenetic relationships within this tribe through parsimony and Bayesian approaches based on 99 morphological characters (including 19 integumental characters, 38 skull characters, 31 dental characters, three postcranial skeletal characters, seven from the male accessory glands and phallus and one from the digestive system) and six molecular markers (one mitochondrial and five nuclear). We include representatives of all, except one, of the currently recognized species of living Abrotrichini plus one fossil form. Based on total evidence, we recovered a primary division between the genus Abrothrix and a group including the long‐clawed Abrotrichini, Chelemys, Geoxus, Notiomys and Pearsonomys. Both clades are recognized and named here as subtribes. The large degree of morphological variation observed within Abrothrix suggests that species in the genus fall into four groups, which we recognize as subgenera. In addition, the two known species of Chelemys do not form a monophyletic group, and Geoxus was recovered as paraphyletic with respect to Pearsonomys. To reconcile classification and phylogenetics, we describe a new genus for Chelemys macronyx and include Pearsonomys as a junior synonym of Geoxus. Our results highlight the importance of both morphology and molecules in resolving the phylogenetic relationships within this tribe. Based on biogeographical analyses, we hypothesize that Abrotrichini originated in south‐western South America by vicariance and then diversified mostly by successive dispersal events.  相似文献   

13.
In northeast China there are large areas of nearly bare soda saline-alkali soil, in which plant survival is exteremely difficult because the land has a pH greater than 10.5. In order to obtain resistant microbial resources able to grow in such conditions, we analyzed environmental microbial samples from this extreme saline-alkali soil region. Through selective culture conditions, 8 bacterial strains were isolated from medium with no less than 1.5 M NaCl, 12 were isolated in the medium with a pH value of no less than 11.0, and 8 were isolated in the medium with of no less than 200 mM Na2CO3. Based on 16S rRNA gene sequence analysis 20 novel strains of bacteria were identified and classified into four groups: 8 group I strains belong to the genus Bacillus; three group II belong to genus Nesterenkonia (2 strains) and genus Zhihengliuella (1 strain); eight group III strains belong to the genera Halomonas (6), Stenotrophomonas (1) and Alkalimonas (1); one group IV strain belongs to genus Litoribacter. These four groups belong to the phylum Firmicutes, phylum Actinobacteria, phylum Gamma-Proteobacteria and phylum Bacteroidetes, respectively. The sequence homology of 16S rRNA in strains ANESC-S, H.sp.C4 and H.sp.C6 with that of known strains was 93.2, 96.5 and 96.5%, respectively. Based on the 97.0% identity cutoff commonly used to discriminate bacterial species, our data suggest that H. sp.C4 and H.sp.C6 may be new species, and ANESC-S may be belong to a new genus of classified into order Cytophagales. The morphological characteristics by scanning electron microscopy (SEM) showed that, in addition to the coccal N.sp.N3, the majority (19) of the isolates are bacilli of various lengths. In culture the colonies appeared red, orange, yellow, light yellow, and milk-white, with milk-white being predominant. Based on the resistance to NaCl and pH, the 20 novel strains were classified into obligate alkaliphilic and halophilic bacteria, obligate alkaliphilic halotolerant bacteria, and facultative alkalophilic salt-tolerant bacteria. This is the first study reporting the isolation and characterization of bacterial resources from extreme saline-alkali soils from northeast China.  相似文献   

14.
Abstract The new species, Foonchewia guangdongensis R. J. Wang & H. Z. Wen and the new monotypic genus Foonchewia R. J. Wang (Rubioideae, Rubiaceae), are described from eastern Guangdong, China. It is characterized by its subshrub habit, pentamerous and heterostylous flowers, 2‐1ocular ovary with many ovules, and apically dehiscent capsules with numerous angulated seeds. Phylogenetic analysis of four chloroplast DNA regions (rbcL, rps16, ndhF, and atpBrbcL) revealed that the new genus is nested in the Spermacoceae alliance and is sister to Dunnia. Morphological comparison between these two genera indicated that they had few synapomorphies; it was therefore inappropriate to classify the new genus in the existing tribe Dunnieae, and a new tribe, Foonchewieae R. J. Wang, is accordingly proposed.  相似文献   

15.
Jeon, M.‐J., Song, J.‐H. & Ahn, K.‐J. (2012). Molecular phylogeny of the marine littoral genus Cafius (Coleoptera: Staphylinidae: Staphylininae) and implications for classification. —Zoologica Scripta, 41, 150–159. A phylogenetic analysis of the marine littoral genus Cafius Stephens is presented based on molecular characters. The data set comprised partial mitochondrial COI (910 bp), COII (369 bp), 12S rDNA (351–354 bp), 16S rDNA (505–509 bp) and nearly complete sequences of 18S rDNA (1814–1830 bp) for 37 species. Twenty‐seven Cafius species, representing five of six subgenera, two Remus Holme species, three Phucobius Sharp species, monotypic Thinocafius Steel and four outgroups were included. The sequences were analysed simultaneously by parsimony analysis in Tree Analysis Using New Technology (TNT) with traditional manual alignment, direct optimization (DO) in the program POY4 under a variety of gap costs and partitioned Bayesian analysis for the combined data. The genus Cafius and nearly all of its subgenera were not supported as being monophyletic. Instead, all analyses (parsimony trees, DO tree under equal weighting and Bayesian tree) showed monophyly of Cafius + Phucobius + Remus + Thinocafius (clade Z) and all seven nested clades (A–G). However, the phylogenetic relationships among clades A–G differed among the analyses. The genus Phucobius was recovered as a monophyletic group within Cafius. The genus Remus was not monophyletic but formed a clade with C. rufescens Sharp and C. rufifrons Bierig within Cafius. The genus Thinocafius formed a clade with C. caviceps Broun, C. litoreus (Broun) and C. quadriimpressus (White) within Cafius. We propose new concepts for the genus Cafius and its related genera, and the seven nested clades.  相似文献   

16.
Abstract. Larvae of the scarabaeoid genera Germarostes Paulian, Cyphopisthes Gestro, Paulianostes Ballerio, Ceratocanthus White, Pterorthochaetes Gestro, Madrasostes Paulian, Astaenomoechus Martínez & Pereira (Ceratocanthidae) and Hybosorus Macleay, Phaeochrous Castelnau, and Anaides Westwood (Hybosoridae) are described, keyed and illustrated with fifty‐seven drawings. A phylogenetic analysis of these two families based on larval morphology is presented. Fifty‐four larval morphological and three biological characters from twenty‐seven taxa revealed nineteen equally parsimonious cladograms. The monophyly of (Ceratocanthidae + Hybosoridae) is supported by four unambiguous unique synapomorphies: dorsal medial endocarina on cranium extended anteriorly into frontal sclerite; presence of large membranous spot on apical antennomere; labium dorsally with four pores in centre (secondarily reduced to two pores in some groups); and presence of stridulatory organ on fore‐ and middle legs (secondarily reduced in some groups). Our analysis suggests that the family Hybosoridae is paraphyletic with respect to Ceratocanthidae. The clade comprising the hybosorid genera Hybosorus and Phaeochrous is the sister group of the remaining Hybosoridae plus Ceratocanthidae. It is supported by two unambiguous synapomorphies: two apical antennomeres completely joined and the stridulatory organ represented by seven to nine large teeth anteriorly on the middle leg. The hybosorid genus Anaides is a sister group to the remaining Hybosoridae plus Ceratocanthidae (without Hybosorus and Phaeochrous) and the ceratocanthid genus Germarostes is a sister group to the remaining Hybosoridae plus Ceratocanthidae (without Hybosorus, Phaeochrous and Anaides). The ceratocanthid genera Cyphopisthes, Astaenomoechus, Paulianostes, Pterorthochaetes, and Madrasostes constitute a sister group to the hybosorid genus Cryptogenius and are supported by the presence of two reversions: two dorsal pores on labium and completely reduced stridulatory organs on fore‐ and middle legs.  相似文献   

17.
This paper describes the habitat preferences of small rodents and shrews from April 1984 to March 1985 in four types of vegetation in a lowland rain forest zone of Nigeria. The vegetation types were high forest, scrub, farmlands and teak plantations in Ogba Forest Reserve, Nigeria. A collection of 359 small mammals, consisting of six species of small rodents and four species of shrews, was made in the study area. The small rodents and their percentage composition were Mus musculoides (26.2%), Praomys tullbergi (16.2%), Mastomys natalensis (7.0%), Lophuromys sikapusi (4.5%), Lemniscomys striatus (2.5%), and Arvicanthis niloticus (1.1%). The shrews were Crocidura nigeriae (19.5%), C. crossei (12.3%), C.grandiceps (7.8%) and C. ftavescens manni (3.1%). The vegetational distribution of the small rodents and shrews is discussed. In the high forest, seven species of small mammals were caught; these were Crocidura nigeriae, C. crossei, C.grandiceps, C.flavescens manni, Mus musculoides, Praomys tullbergi and Lophuromys sikapusi. Mus musculoides, Crocidura nigeriae and Praomys tullbergi were more abundant in the high forest. All the species of small mammals recorded in the study area, except Arvicanthis niloticus, were found in the scrub. In the farmlands, all ten species of small mammals were trapped. Mus musculoides was the commonest species in the farmlands. Three species of shrews, Crocidura crossei, C. grandiceps and C.flavescens manni, and also two species of small rodents, Mus musculoides and Mastomys natalensis were caught in the teak plantation. The reproductive data for Mus musculoides, Crocidura nigeriae and Praomys tullbergi show that breeding in these species occurs throughout most months of the year. Fecundity appears to be maximal in the wet season in Mus musculoides and Crocidura nigeriae and in the dry season in the case of Praomys tullbergi.  相似文献   

18.
During the last two decades, major taxonomic rearrangements were instituted in the anuran family Ranidae. Most of these changes were not based on phylogenetic analysis, and many are controversial. Addressing the phylogeny of Ranidae requires broader taxon sampling within the superfamily Ranoidea, the phylogenetic relationships and higher classification of which are also in a state of flux. No comprehensive attempt has yet been made to reconstruct ranid phylogeny using both morphological and molecular data. In the present contribution, data from 178 organismal characters were collated for 74 exemplar species representing the families Arthroleptidae, Hemisotidae, Hyperoliidae, Mantellidae Microhylidae, Petropedetidae, Rhacophoridae, Sooglossidae, and most subfamilies of Ranidae. These were combined with ~1 kb of DNA sequence from the mitochondrial 12S rDNA and 16S rDNA gene regions in a simultaneous parsimony analysis with direct optimization. Results support the classification of Hemisus with the brevicipitine microhylids, confirm that Arthroleptidae (and its two component subfamilies Astylosterninae and Arthroleptinae) are monophyletic, and advocate the recognition of Leptopelidae. Monophyly of Ranidae is compromised by recognition of Petropedetidae, Rhacophoridae and Mantellidae, which should be recognized as subfamilies of Ranidae at present. Furthermore, Petropedetidae was found to be grossly paraphyletic, comprising three clades which are all considered separate subfamilies of Ranidae, i.e., Petropedetinae, Phrynobatrachinae and Cacosterninae. Three well defined subfamilies of Ranidae were consistently retrieved as monophyletic in a sensitivity analysis, i.e., Tomopterninae, Ptychadeninae and Pyxicephalinae. However, Ptychadeninae and Pyxicephalinae were embedded in Raninae and Dicroglossinae, respectively. Ceratobatrachinae is removed from Dicroglossinae. Dicroglossinae is synonymized with Pyxicephalinae. A new subfamily Strongylopinae is proposed. Raninae should be conservatively treated as a “metataxon” (sensu Ford and Cannatella, 1993 ) until such time as it is fully revised. Tomopterninae is removed from synonymy with Cacosterninae. Morphological synapomorphies are reported for major monophyletic clades retrieved in the simultaneous analysis with equal weights. The present study found that many Old World clades appear to contain both African and Asian taxa, contrary to the findings of some recent biogeographical analyses. This study demonstrates the value of broad taxonomic sampling in ranid phylogeny, and highlights the immense contribution that can be made from detailed morphological data. © The Willi Hennig Society 2005.  相似文献   

19.
The sequences of the internal transcribed spacers (ITS regions) and the 5.8S rRNA gene, together with the electrophoretic karyotypes of 27 strains representative of the six species belonging to the genus Hanseniaspora, were examined. From the analysis of the 5.8S rRNA gene and the ITS regions, the genus Hanseniaspora is monophyletic and can be divided into two subgroups. This subdivision was supported by electrophoretic chromosome patterns. Hanseniaspora guilliermondii, H. uvarum and H. valbyensis show 6–7 bands (8 to 9 chromosomes), while the second group comprises the species H. occidentalis, H. osmophila and H. vineae which have only 5 chromosomes.  相似文献   

20.
Oxovanadium clusters provide novel examples of large magnetic clusters, which may showin nuce the typical behavior of bulk magnetic materials.The paper reviews the magnetic properties of V15, comprising fifteen oxovanadium(IV); V14, comprising fourteen oxovanadium(IV); V3+1, comprising three localized oxovanadium(IV), six localized oxovanadium(V), and one oxovanadium(IV) delocalized over three sites; V4+2 and V4+4 which comprise four localized and two and four delocalized oxovanadium(IV), respectively. The different observed magnetic behaviors are discussed on the basis of several models of different sophistication.  相似文献   

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