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1.
Poecilostome cyclopoids are among the most morphologically diverse copepods, having established symbiotic relationships with teleosts, elasmobranchs and invertebrate hosts belonging to no fewer than 14 marine phyla. Many parasitic lineages display radically divergent body plans and on that basis have traditionally been placed at higher taxonomic rank than they deserve. The most recent example is the monotypic family Umazuracolidae, established for a derived fish parasite with bomolochiform affinities. Phylogenetic analysis of complete ssrDNA (18S) sequences of 44 species belonging to 21 families of cyclopoid copepods shows that there is no support for the familial distinctiveness of the Umazuracolidae. Both maximum parsimony tree reconstruction and Bayesian inference, operating under the GTR+I+Γ model of nucleotide substitution, unambiguously placed Umazuracola elongatus in the Taeniacanthidae within the predominantly fish parasitic bomolochiform complex, refuting the original suggestion of a shared most recent common ancestry with polychaete symbionts. The phylogenies also revealed that the bomolochiform families and the Clausidiidae (and allies) form a monophyletic group, the clausidiiform complex, with high nodal support under both methods. Bayesian inference suggested a diphyletic origin of the "Poecilostomatoida" with the clausidiiform family-group holding a basal position while the traditional cyclopoid families form a monophyletic group in apposition to a second poecilostomatoid clade; however, maximum parsimony results were equivocal, depending on outgroup selection. Scrutiny of the morphological characters diagnosing the monotypic families Tegobomolochidae and Tuccidae demonstrated that they merely represent derived lineages within more inclusive taxa, the former being related to a group of nostril-inhabiting genera within the Bomolochidae, the latter forming the sistergroup of Taeniacanthodes within the Taeniacanthidae. The taeniacanthid genus Makrostrotos occupies a position at the base of the bomolochiform complex and is fixed as the type of a new family, Makrostrotidae. Although both morphological and molecular evidence hint that the Bomolochidae is nested within a paraphyletic Taeniacanthidae, the status quo of maintaining both families is favoured here pending additional molecular data. The bomolochiform complex, comprising the Bomolochidae, Taeniacanthidae, Telsidae and Makrostrotidae, is attributed superfamilial rank as the Bomolochoidea. A recent controversial phylogenetic analysis of the poecilostomatoid families is shown to be flawed, being based on a dataset containing imperfect or misleading information, and characters whose states were wrongly assessed.  相似文献   

2.
Bifidobacterium lactis JCM 10602T (T = type strain) and Bifidobacterium animalis JCM 1190T were found to be phenotypically similar. These strains were subjected to investigation of their genetic relationships. The 16S rRNA sequence of B. animalis JCM 1190T was aligned with that of other Bifidobacterium species. B. animalis and B. lactis were the most closely related species in the phylogenetic tree and showed a high similarity in sequences (98.8%). The levels of DNA-DNA hybridization between the type strains of B. lactis and B. animalis ranged from 85.5 to 92.3%, showing that they represent a single species. It is proposed that B. lactis should be considered as a junior subjective synonym of B. animalis.  相似文献   

3.
Five strains of bifidobacteria were isolated from faeces of a common marmoset (Callithrix jacchus) and a red-handed tamarin (Saguinus midas). The five isolates clustered inside the phylogenetic group of the genus Bifidobacterium but did not show high sequence similarities between the isolates and to known species in the genus by phylogenetic analysis based on 16S rRNA gene sequences. Sequence analyses of dnaJ1 and hsp60 also indicated their independent phylogenetic positions to each other in the Bifidobacterium cluster. DNA G+C contents of the species ranged from 57.3 to 66.3 mol%, which is within the values recorded for Bifidobacterium species. All isolates showed fructose-6-phosphate phosphoketolase activity. Based on the data provided, the five isolates represent five novel species, for which the names Bifidobacterium reuteri sp. nov. (type strain: AFB22-1(T) = JCM 17295(T) = DSM 23975(T)), Bifidobacterium callitrichos sp. nov. (type strain: AFB22-5(T) = JCM 17296(T) = DSM 23973(T)), Bifidobacterium saguini sp. nov. (type strain: AFB23-1(T) = JCM 17297(T) = DSM 23967(T)), Bifidobacterium stellenboschense sp. nov. (type strain: AFB23-3(T) = JCM 17298(T) = DSM 23968(T)) and Bifidobacterium biavatii sp. nov. (type strain: AFB23-4(T) = JCM 17299(T) = DSM 23969(T)) are proposed.  相似文献   

4.
Two Gram-negative, nonmotile, coccobacilli, SW-3T and SW-100T, were isolated from sea water of the Yellow Sea in Korea. Strains SW-3T and SW-100T contained ubiquinone-9 (Q-9) as the predominant respiratory lipoquinone and C18:1 omega9c and C16:0 as the major fatty acids. The DNA G+C contents of strains SW-3T and SW-100T were 44.1 mol% and 41.9 mol%, respectively. A neighbor-joining tree based on 16S rRNA gene sequences showed that the two isolates fell within the evolutionary radiation enclosed by the genus Acinetobacter. Strains SW-3T and SW-100T exhibited a 16S rRNA gene similarity value of 95.7% and a mean DNA-DNA relatedness level of 9.2%. Strain SW-3T exhibited 16S rRNA gene sequence similarity levels of 93.5-96.9% to the validly described Acinetobacter species and fifteen Acinetobacter genomic species. Strain SW-100T exhibited 16S rRNA gene sequence similarity levels of less than 97.0% to the other Acinetobacter species except Acinetobacter towneri DSM 14962T (98.0% similarity). Strains SW-3T and SW-100T exhibited mean levels of DNA-DNA relatedness of 7.3-16.7% to the type strains of some phylogenetically related Acinetobacter species. On the basis of phenotypic, phylogenetic, and genetic data, strains SW-3T and SW-100T were classified in the genus Acinetobacter as two distinct novel species, for which the names Acinetobacter marinus sp. nov. (type strain SW-3T=KCTC 12259T=DSM 16312T) and Acinetobacter seohaensis sp. nov. (type strain SW-100T=KCTC 12260T=DSM 16313T) are proposed, respectively.  相似文献   

5.
Four strains of yeasts isolated in Thailand and Taiwan were found to represent four distinct novel species of the ascomycetous anamorphic yeast genus Candida. These strains are located in the Clavispora-Metschnikowia clade in a phylogenetic tree based on the D1/D2 domain sequences of the large subunit rRNA genes. Together with Candida picinguabensis and Candida saopaulonensis, the four novel species constitute a well-separated subclade from other species of the Clavispora-Metschnikowia clade. Three species from Thailand are described as Candida bambusicola sp. nov. (type strain, ST-50(T) = BCC 7750(T) = NBRC 106734(T) = CBS 11723(T)), Candida nongkhaiensis sp. nov. (type strain, ST-95(T) = BCC 8331(T) = NBRC 105874(T) =CBS 11724(T)) and Candida succicola sp. nov. (type strain, ST-631(T) = BCC 15314(T) = NBRC 106736(T) = CBS 11726(T)), respectively, and the species from Taiwan is described as Candida touchengensis sp. nov. (type strain, SY4S03(T) = NBRC 102647(T) = BCRC 23097(T) = CBS 10585(T)).  相似文献   

6.
To set the stage for historical analyses of the ecology and behavior of tree swallows and their allies (genus Tachycineta), we reconstructed the phylogeny of the nine Tachycineta species by comparing DNA sequences of six mitochondrial genes: Cytochrome b (990 base pairs), the second subunit of nicotinamide adenine dinucleotide dehydrogenase (839 base pairs), cytochrome oxidase II (85 base pairs), ATPase 8 (158 base pairs), tRNA-lysine (73 base pairs), and tRNA-methionine (25 base pairs). The phylogeny consisted of two main clades: South and Central American species ((T. stolzmanni, T. albilinea, T. albiventris), (T. leucorrhoa, T. meyeni)), and North American and Caribbean species (T. bicolor, (T. thalassina, T. euchrysea, T. cyaneoviridis)). The genetic distances among the species suggested that Tachycineta is a relatively old group compared to other New World swallow genera. One interesting biogeographic discovery was the close relationship between Caribbean and western North American taxa. This historical connection occurs in other groups of swallows and swifts as well. To reconstruct the phylogeny, we employed Bayesian as well as traditional maximum-likelihood methods. The Bayesian approach provided probability values for trees produced from the different genes and gene combinations, as well as probabilities of branches within those trees. We compared Bayesian and maximum-likelihood bootstrap branch support and found that all branches with Bayesian probabilities > or = 95% received bootstrap support >70%.  相似文献   

7.
The taxonomic position of two soil isolates, strains A288(T) and A290(T) [provisionally assigned to the genus Actinomadura] was clarified in a polyphasic study. The organisms showed a combination of chemotaxonomic and morphological properties typical of actinomadurae. They also formed distinct phyletic lines in the 16S rRNA Actinomadura gene tree; strain A288(T) was associated with A. nitritigenes whereas strain A290(T) was closely related to a group that consisted of A. citrea, A. coerulea, A. glauciflava, A. luteofluorescens and A. verrucosospora. Strains A288(T) and A290(T) showed key phenotypic features which readily distinguish them from one another and from representatives of related validly described species of Actinomadura. It is proposed that the two organisms be classified as new species of the genus Actinomadura. The names proposed for the new taxa are Actinomadura mexicana (A290(T) = DSM 44485(T) = NRRL B-24203(T)), and Actinomadura meyerii (A288(T) = DSM 44485(T) = NRRL B-24203(T)).  相似文献   

8.
Gene trees will often differ from the true species history, the species tree, as a result of processes such as incomplete lineage sorting. New methods such as Bayesian Estimation of the Species Tree (BEST) use the multispecies coalescent to model lineage sorting, and directly infer the species tree from multilocus DNA sequence data. The Sulidae (Aves: Pelecaniformes) is a family of ten booby and gannet species with a global distribution. We sequenced five nuclear intron loci and one mitochondrial locus to estimate a species tree for the Sulidae using both BEST and by concatenating nuclear loci. We also used fossil calibrated strict and relaxed molecular clocks in BEAST to estimate divergence times for major nodes in the sulid phylogeny. Individual gene trees showed little phylogenetic conflict but varied in resolution. With the exception of the mitochondrial gene tree, no gene tree was completely resolved. On the other hand, both the BEST and concatenated species trees were highly resolved, strongly supported, and topologically consistent with each other. The three sulid genera (Morus, Sula, Papasula) were monophyletic and the relationships within genera were mostly consistent with both a previously estimated mtDNA gene tree and the mtDNA gene tree estimated here. However, our species trees conflicted with the mtDNA gene trees in the relationships among the three genera. Most notably, we find that the endemic and endangered Abbott's booby (Papasula abbotti) is likely basal to all other members of the Sulidae and diverged from them approximately 22 million years ago.  相似文献   

9.
From approximately 200 basidiomycetous yeast isolates forming orange or orange-red colonies isolated from senescent leaves collected in different regions of China, 29 representative strains varying in their geographic distribution and ballistoconidium forming ability were selected for further phenotypic and molecular taxonomic studies. Sequence analysis of the large subunit (26S) rDNA D1/D2 domain and the internal transcribed spacer (ITS) region including 5.8S rRNA from the strains resulted in the recognition of seven Dioszegia species, including four described species, namely D. aurantiaca, D. fristingensis, D. hungarica and D. zsoltii var. zsoltii and D. zsoltii var. yunnanensis, and three undescribed species. The three new species are described as Dioszegia athyri sp. nov. (type strain: CB 159(T) = AS 2.2559(T) = CBS 10119(T)), Dioszegia butyracea sp. nov. (type strain: CB 261(T) = AS 2.2600(T) = CBS 10122(T)) and Dioszegia xingshanensis sp. nov. (type strain: HB 1.4(T) = AS 2.2481(T) = CBS 10120(T)) in the present study.  相似文献   

10.
In a taxonomic study on the ascomycetous yeasts isolated from plant materials collected in tropical forests in Yunnan and Hainan Provinces, southern China, four strains isolated from tree sap (YJ2E(T)) and flowers (YF9E(T), YWZH3C(T) and YYF2A(T)) were revealed to represent four undescribed yeast species. Molecular phylogenetic analysis based on the large subunit (26S) rRNA gene D1/D2 domain sequences showed that strain YJ2E(T) was located in a clade together with Candida haemulonii and C. pseudohaemulonii. Strain YF9E(T) was most closely related to C. azyma and strain YWZH3C(T) to C. sorbophila and C. spandovensis. Strain YYF2A(T) was clustered in a clade containing small-spored Metschnikowia species and related anamorphic Candida species. The new strains differed from their closely related described species by more than 10% mismatches in the D1/D2 domain. No sexual states were observed for the four strains on various sporulation media. The new species are therefore assigned to the genus Candida and described as Candida alocasiicola sp. nov. (type strain, YF9E(T) = AS 2.3484(T) = CBS 10702(T)), Candida hainanensis sp. nov. (type strain, YYF2A(T) = AS 2.3478(T) = CBS 10696(T)), Candida heveicola sp. nov. (type strain, YJ2E(T) = AS 2.3483(T) = CBS 10701(T)) and Candida musiphila sp. nov. (type strain, YWZH3C(T) = AS 2.3479(T) = CBS 10697(T)).  相似文献   

11.
The phylogeny of nematodes in the family Protostrongylidae (Nematoda: Metastrongyloidea) was reconstructed by cladistic analysis of 28 binary and multistate characters derived from comparative morphology. Analyses were hierarchical, and examined (1) relationships among genera, including 13 ingroup taxa and Metastrongylidae as an outgroup (single tree, 78 steps, consistency index [CI] = 0.705); and (2) relationships among genera and species groups, including 21 ingroup taxa and Metastrongylus apri as an outgroup (single tree, 76 steps, CI = 0.582). In the species-level tree, Protostrongylidae was divided into 2 major clades, 1 containing the subfamilies Muelleriinae (including the recently described Umingmtakstrangylus pallikuukensis), Elaphostrongylinae, and the Varestrongylinae (excluding Pneumocaulus kadenazii). Varestrongylus was paraphyletic as it included Pneumostrongylus calcaratus. The second major clade consisted of a paraphyletic group containing Protostrongylus spp. and Spiculocaulus leuckarti and, basal to this subclade, several other individual protostrongylid lineages. The various subclades generally correspond to the subfamilial divisions of the Protostrongylidae. The Neostrongylinae, however, is not supported as Neostrongylus and Orthostrongylus are not sister groups. Based on a large number of hypothesized synapomorphies, the elaphostrongylines appear to be a highly derived group of protostrongylids, a feature potentially correlated with their habitat localization in muscular and nervous tissues. The generic-level tree retained most of the primary structure revealed among the species but excluded the varestrongylines from the Muelleriinae + Elaphostrongylinae subclade. Artiodactyles of the family Cervidae are considered basal hosts for protostrongylids; secondary colonization in Caprini, Rupicaprini, and among lagomorphs is postulated.  相似文献   

12.
Trioza hopeae sp. nov. is described and illustrated from Vietnam. Trioza hopeae develops on Hopea odorata, a valuable timber tree on which it causes serious damage by inducing leaf galls. The new species is closely related to Trioza minuta (Mathur) comb. nov. (from Ceropsylla Riley), an Indian species associated with Shorea robusta. Differences between the two species are discussed. Another five Indian species are transferred here from Ceropsylla to Trioza Foerster as T. ferruginea ( Mathur, 1975 ) comb. nov., T. fulvida ( Mathur, 1975 ) comb. nov., T. indica ( Kandasamy, 1986 ) comb. nov., T. longivenata ( Kandasamy, 1986 ) comb. nov., and T. parvus ( Kandasamy, 1986 ) comb. nov.  相似文献   

13.
Z W Liu  R R Wang 《Génome》1993,36(1):102-111
To elucidate the genome constitutions of the tetraploid (2n = 4x = 28) species Elytrigia caespitosa, Lophopyrum nodosum, and Pseudoroegneria geniculata ssp. scythica and the hexaploid (2n = 6x = 42) Thinopyrum intermedium, meiotic pairing was studied in these species as well as 10 hybrids. Karyotype analysis with aceto-orcein stained root-tip cells was performed for the four species and the hybrids of T. bessarabicum with E. caespitosa, P. geniculata ssp. scythica, and T. intermedium. Karyotype analysis by Giemsa C-banding was carried out with the three tetraploid species and the two triploid hybrids involving T. bessarabicum. The species behaved as strict allopolyploids. All hybrids were male sterile with few stainable pollen grains. It is concluded from the results that the three tetraploid species have the genome formula JeJeSS and T. intermedium has the formula JeJeJeJeSS. The chromosomes of the Je and S genomes in these species had C-banding patterns differing from each other and from those of the extant diploid species. Based on these findings, the four species investigated should be placed in the same genus or the same section of a genus. However, new combinations are not proposed at this time pending future taxonomic investigation of the genome constitution of Elytrigia repens (L.) Nevski.  相似文献   

14.
Termites usually build nests differently shaped and characterized according to each species, to protect and keep society cohesion. Some species build nests in the ground, some prefer tree thunks or branches as support, whereas other dig galleries in the wood. The purpose of this study is to analyze the relationship between the occurrence of arboreal termites Constrictotermes cyphergaster Silvestri and tree species that support the nest of this species, in a Cerrado sensu strictu of the Serra de Caldas Novas, GO. Data suggest a association relationship between C. Cyphergaster and the tree species Qualea grandiflora Mart., Annona crassiflora Mart., Caryocar brasiliense Camb. and Plathymenia reticulata Benth., shown by high Qui-squared values (chi2 = 214.986, gl. = 20, P < 0.001). This relationship may be found among other termites and tree species, including Cerrado biome, and may be due to several factors, such as natural competitors and predators, toxin production by other tree species or benefits between associated species (facultative mutualism or facilitation).  相似文献   

15.
Corinne A.  Lynch 《Journal of Zoology》1989,219(4):545-567
Two new species of Tyrophagus Oudemans, 1924, are described. One species, T. Savasi , has been discovered in several habitats of economic importance. It closely resembles T putrescentiae (Schrank) and T. neiswander Johnston & Bruce. The second, T. rebertsonae , has so far been discovered in only two, soil and tree bark. It differs from other species of Tyrophagus by a number of character. Both new species have pigmented 'eyespots' on the prodorsal shield. A new character used to differentiate these species is the shape of the sclerotized neck of receptaculum semins.
The position of the new species in three commonly used keys to adults of the genus Tyrophagus is indicated  相似文献   

16.
BACKGROUND AND AIMS: The discovery of a new species, Haplophyllum bastetanum F.B. Navarro, V.N. Suárez-Santiago & Blanca sp. nov., in the south-east of Spain has prompted the comparative study of species of the Iberian Peninsula, and others related, through morphological, cytogenetic, molecular, distributional and ecological characterization. METHODS: The morphological study involved a quantitative analysis of the species present in the Iberian Peninsula and a comparative analysis of the morphological characteristics between H. bastetanum and other related species. Mitotic analyses were made with root meristems taken from germinating seeds. Phylogenetic analyses of the internal transcribed spacer sequences of nuclear ribosomal DNA were performed using neighbour-joining (NJ) and maximum-parsimony methods. KEY RESULTS: Haplophyllum bastetanum is a diploid species (2n = 18) distinguished primarily for its non-trifoliate glabrous leaves, lanceolate sepals, dark-green petals with a dorsal band of hairs, and a highly hairy ovary with round-apex locules. The other two Iberian species (H. linifolium and H. rosmarinifolium) are tetraploid (2n = 36) and have yellow petals. Both phylogenetic methods generated a well-supported clade grouping H. linifolium with H. rosmarinifolium. In the NJ tree, the H. linifolium-H. rosmarinifolium clade is a sister group to H. bastetanum, while in the parsimony analysis this occurred only when the gaps were coded as a fifth base and the characters were reweighted according to the rescaled consistency index. This latter group is supported by the sequence divergence among taxa. CONCLUSIONS: The phylogenies established from DNA sequences together with morphological and cytogenetic analyses support the separation of H. bastetanum as a new species. The results suggest that the change in the number of chromosomes may be the key mechanism of speciation of the genus Haplophyllum in the Iberian Peninsula. An evolutionary scheme for them is propounded.  相似文献   

17.
This work deals with the taxonomic study of 12 orange-pigmented bacteria isolated from permafrost sediments, rice plots, and soils contaminated with wastes from the chemical and salt industries, which were assigned to the genus Brevibacterium on the basis of phenotypic characteristics, as well as of some strains described previously as Brevibacterium linens. The study revealed three genomic species, whose members and the type strains of the closest species of Brevibacterium had DNA similarity levels between 24 and 59%. The strains of the genomic species differed from each other and from the known species of Brevibacterium in some physiological and biochemical characteristics, as well as in the sugar and polyol composition of their teichoic acids. The 16S rDNA sequence analysis confirmed the assignment of the environmental isolates to the genus Brevibacterium and showed the phylogenetic distinction of the three genomic species. The results obtained in this study allow three new Brevibacterium species to be described: Brevibacterium antiquum (type strain VKM Ac-2118T = UCM Ac-411T), Brevibacterium aurantiacum (type strain VKM Ac-2111T = NCDO 739T = ATCC 9175T), and Brevibacterium permense (type strain VKM Ac-2280T = UCM Ac-413T).  相似文献   

18.
19.
Three new yeast species, Candida kashinagacola (JCM 15019(T) = CBS 10903(T)), C. pseudovanderkliftii (JCM 15025(T) = CBS 10904(T)), and C. vanderkliftii (JCM 15029(T) = CBS 10905(T)) are described on the basis of comparison of nucleotide sequences of large subunit ribosomal DNA D1/D2 region (LSU rDNA D1/D2). The nearest assigned species of the three new species was Candida llanquihuensis. Candida kashinagacola and C. pseudovanderkliftii differed from C. llanquihuensis by 3.8% nucleotide substitution of the region, while C. vanderkliftii did by 4.4%. Three new species differed in a number of physiological and growth characteristics from any previously assigned species and from one another. A phylogenetic tree based on the sequences of LSU rDNA D1/D2 showed that these new species together with Candida sp. ST-246, Candida sp. JW01-7-11-1-4-y2, Candida sp. BG02-7-20-001A-2-1 and C. llanquihuensis form a clade near Ambrosiozyma species. The new species did not assimilate methanol as a sole source of carbon, which supported the monophyly of these non methanol-assimilating species which are closely related to the methylotrophic yeasts. Candida kashinagacola was frequently isolated from the beetle galleries of Platypus quercivorus in three different host trees (Quercus serrata, Q. laurifolia and Castanopsis cuspidata) located in the sourthern part of Kyoto, Japan, thus indicating that this species may be a primary ambrosia fungus of P. quercivorus. On the other hand, C. pseudovanderkliftii and C. vanderkliftii were isolated only from beetle galleries in Q. laurifolia. Candida vanderkliftii was isolated from beetle gallery of Platypus lewisi as well as those of P. quercivorus. Candida pseudovanderkliftii and C. vanderkliftii are assumed to be auxiliary ambrosia fungi of P. quercivorus.  相似文献   

20.
选用寄生红蜡蚧的扁角跳小蜂属(Anicetus)6个种的14个形态特征和2个其他特征(寄主种数和是否寄生软蚧)作为内群性状,以柯氏花翅跳小蜂(Microterys clauseni)作为外群,运用PAUP(Version 4.0b10)程序做了支序分析。所得支序树状图有如下参数:树长=28;一致性指数=0.6786;稳定性指数=0.4375。6种扁角跳小蜂中,亲缘关系表示为:(A.annulatus,((A.rubensi,(A.beneficus,A.rarisetus)),(A.howardi,A.ohgushii)))。软蚧扁角跳小蜂(A.annulatus)与其他5个种的亲缘关系相对较远,与传统分类学观点一致。  相似文献   

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