AFLP markers support separation of Solanum nodiflorum from Solanum americanum sensu stricto (Solanaceae)

This study was aimed at examining the relationships between the African material of Solanum americanum (also designated as S. nodiflorum), accessions of this taxon from other geographical areas, and American S. americanum using AFLP markers. 96 individuals representing 39 accessions of S. americanum sensu lato and related diploid species from the widest possible geographical range, and one accession of S. dulcamara (as outgroup) were used. The AFLP results suggested that American S. americanum differs from S. nodiflorum and that the material investigated in this study can be assigned to three different species: S. americanum sensu stricto, S. nodiflorum and a Solanum species from Brazil. These species can be differentiated based on a combination of floral and fruit characteristics.     

广西兰科植物二新记录属

该文报道了广西兰科(Orchidaceae) 2个新记录属,即鹿角兰属(Pomatocalpa Breda)和独花兰属(Changnienia S. S. Chien)。鹿角兰属植物共有13种,中国分布有2种,广西首次记录到该属的台湾鹿角兰[Pomatocalpa undulatum (Lindley) J. J. Smith subsp. acuminatum (Rolfe) S. WatthanaS. W. Chung];独花兰属为单种属,仅独花兰(Changnienia amoena S. S. Chien) 1种,该种为中国特有种,广西首次记录。该文还提供了新记录属和种的形态描述和图片。     

Ribotyping of 16S and 23S rRNA genes and organization of rrn operons in members of the bacterial genera Gemmata,Planctomyces, Thermotoga,Thermus, and Verrucomicrobium

The number of organization of rrn genes of two members of the order Planctomycetales, Planctomyces limnophilus and Gemmata obscuriglobus, as well as three species from other bacterial phyla, namely Thermotoga maritima, Thermus aquaticus and Verrucomicrobium spinosum were examined by Southern blot hybridization analysis of restricted DNA with labeled 16S- and 23S rRNAs. Ribotyping analysis revealed that two species contain unlinked 16S- and 23S rRNA genes. Planctomyces limnophilus possessed two unlinked rrn genes which were separated from each other by at least 4.3 kb, and Thermus aquaticus had to unlinked 16S and 23S rRNA genes, separated from each other by at least 2.5 kb. Gemmata obscuriglobus exhibited five genes for which the organization could as yet not be determined because of the complex hybridization patterns. In the other two species, rrn genes clustered in operons. Thermotoga maritima had a single gene for each rRNA species which were separated by not more than 1.5 kb, while Verrucomicrobium spinosum had four copies of probably linked 16S and 23S rRNA genes with a maximal distance between 16S and 23S rRNA genes of 1.3 kb.     

The Symbiotic Requirements of Different Medicago Spp. Suggest the Evolution of Sinorhizobium Meliloti and S. Medicae with Hosts Differentially Adapted to Soil pH

Nitrogen fixing rhizobia associated with the Medicago L. genus belong to two closely related species Sinorhizobium medicae and S. meliloti. To investigate the symbiotic requirements of different Medicago species for the two microsymbionts, 39 bacterial isolates from nodules of eleven Medicago species growing in their natural habitats in the Mediterranean basin plus six historical Australian commercial inocula were symbiotically characterized with Medicago hosts. The bacterial species allocation was first assigned on the basis of symbiotic proficiency with M. polymorpha. PCR primers specific for 16S rDNA were then designed to distinguish S. medicae and S. meliloti. PCR amplification results confirmed the species allocation acquired in the glasshouse. PCR fingerprints generated from ERIC, BOXA1R and nif-directed RPO1 primers revealed that the Mediterranean strains were genetically heterogenous. Moreover PCR fingerprints with ERIC and BOX primers showed that these repetitive DNA elements were specifically distributed and conserved in S. meliloti and S. medicae, clustering the strains into two divergent groups according to their species. Linking the Sinorhizobium species with the plant species of origin we have found that S. medicae was mostly associated with medics well adapted to moderately acid soils such as M. polymorpha, M. arabica and M. murex whereas S. meliloti was predominantly isolated from plants naturally growing on alkaline or neutral pH soils such as M. littoralis and M. tornata. Moreover in glasshouse experiments the S. medicae strains were able to induce well-developed nodules on M. murex whilst S. meliloti was not infective on this species. This feature provides a very distinguishing characteristic for S. medicae. Results from the symbiotic, genotypic and cultural characterization suggest that S. meliloti and S. medicae have adapted to different Medicago species according to the niches these medics usually occupy in their natural habitats.     

Interspecific Relationships among Charrs Based on Phylogenetic Analysis of Nuclear Growth Hormone Intron Sequences

DNA samples were obtained from six charr species: Salvelinus alpinus, S. malma, S. confluentus, S. leucomaenis, S. namaycush and S. fontinalis and two outgroups: Salmo salar and S. trutta. The C and D introns from the duplicate growth hormone loci (GH1 and GH2) were amplified using the polymerase chain reaction and sequenced from each of the species. Phylogenetic analyses with and without gaps were performed using the beta version of PAUP. The GH introns are evolving relatively slowly, so the data were combined with sequences from the ITS1 and ITS2 for a phylogenetic analysis of the charr species. The GH intron data and the combined data supported two groups of sister species among charrs: S. alpinus and S. malma, and S. confluentus and S. leucomaenis.     

New species of Solanum and Capsicum (Solanaceae) from Bolivia, with clarification of nomenclature in some Bolivian Solanum

Nine new species ofSolanum and two ofCapsicum are described from Bolivia. Notes are provided on some other species, including the complex typification ofSolanum aridum.Capsicum caballeroi, C. ceratocalyx, Solanum chalmersii, S. clandestinum, S. comarapanum, S. complectens, S. monanthemon, S. moxosense, S. pedemontanum, S. saturatum, andS. whalenii are described and illustrated, and a new name,S. scuticum, is proposed for the species previously known asS. tabacifolium.     

Molecular evidence for the taxonomic status of three species of the <Emphasis Type="Italic">Sphyraena obtusata</Emphasis> group (Perciformes: Sphyraenidae) from East Asia

Genetic differences among the three species of Sphyraena with two gill rakers from East Asia (S. iburiensis, S. obtusata, and S. pinguis, defined recently as the S. obtusata group), were investigated using 799-bp sequences of the mitochondrial cytochrome b gene. Pairwise sequence differences within each of the three species were 0.0–0.4% (S. iburiensis), 0.0–0.4% (S. obtusata), and 0.0–0.6% (S. pinguis), respectively, pairwise sequence differences among the three species being 18.3–18.6% (S. iburiensis vs. S. obtusata), 14.9–15.4% (S. iburiensis vs. S. pinguis), and 17.6–18.3% (S. obtusata vs. S. pinguis), respectively. The extent of the latter were comparable to those among four other congeneric species, S. africana, S. forsteri, S. helleri, and S. japonica (16.0–24.5%). Phylogenetic analysis using the maximum-likelihood method indicated reciprocal monophyly of the three species, each clade being supported by a bootstrap value of 100%. These findings fully supported the taxonomic status of these species, recently elucidated by detailed morphological comparisons. In addition, the S. obtusata group formed a strongly supported clade against the four other congeneric species.     

Sedum surculosum andS. jaccardianum (Crassulaceae) share a unique 70 bp deletion in the chloroplast DNA trnL (UAA)-trnF (GAA) intergenic spacer

TrnL (UAA)-trnF (GAA) chloroplast DNA spacer sequences of three species ofMonanthes, Sedum surculosum (=Monanthes atlanticum) andS. jaccardianum were compared.S. surculosum, the systematic position of which has been disputed ever since its discovery, shares a phylogenetically highly significant 70 bp deletion withS. jaccardianum. In addition to this large deletion the two Moroccan species ofS. ser.Monanthoidea differ in three more indels as well as in four nucleotide substitutions from the species ofMonanthes. These data render strong support for the monophyly ofS. ser.Monanthoidea andMonanthes. Spacer length in seven species and one subspecies ofMonanthes is relatively uniform.     

银白色葡萄球菌的发现、分布与致病性

银白色葡萄球菌(Staphylococcus argenteus)是金黄色葡萄球菌(S. aureus)的近缘新种,于2015年正式被鉴定、命名。在此之前,银白色葡萄球菌一直被认为是金黄色葡萄球菌种内的一个远源支系。该物种绝大多数菌株分离自人体,基因组上含有大量与金黄色葡萄球菌同源的毒力基因,可导致与金黄色葡萄球菌类似的临床感染和食物中毒症状。因为与人类健康相关,银白色葡萄球菌受到了越来越多的关注,目前已在20多个国家被报道。但是由于出现较晚,与金黄色葡萄球菌难以区分,银白色葡萄球菌的全球分布状况、原始生境和传播过程尚不清楚。本文从发现过程、分布、致病性和鉴定方法等方面综述了银白色葡萄球菌的最新研究进展。     

Alkaloids of theSedum acre-group (Crassulaceae)

The 16 species of theSedum acre-group were investigated for the presence of alkaloids. They areS. acre ofS. ser.Acria, S. alpestre, S. annuum, S. apoleipon, S. borissovae, S. euxinum, S. grisebachii, S. laconicum, S. multiceps, S. sexangulare, S. tuberiferum, S. tuberosum, S. ursi, andS. urvillei ofS. ser.Alpestria, S. samium ofS. ser.Samia, andS. litoreum ofS. ser.Litorea. S. acre differs significantly from the other species. It contains sedamine, hydroxy sedamine, and a number of 2,6-disubstituted piperidine alkaloids. The leafy parts of the species ofS. ser.Alpestria, S. ser.Samia, andS. ser.Litorea contain 4 piperidine alkaloids which also occur inS. acre, and in addition 4 pyrrolidine alkaloids not present inS. acre. The composition of the alkaloid fraction agrees with the infrageneric classification (series) based on the hybridization patterns of the species (comparia).     

Reproductive ecology of five pipefish species in one eelgrass meadow

Synopsis Synopsis Pipefishes have rarely been watched in the wild and have never before been followed in their common seagrass habitats. This study explores the reproductive ecology of five species of pipefishes living in a Swedish eelgrass meadow during parts of four breeding seasons, tagging four of the species. Pipefish are remarkable for their specialised paternal care: only males aerate, osmoregulate and nourish the developing embryos. Two of the species (Entelurus aequoreus andNerophis ophidion) have simple ventral gluing of eggs on the trunk while three species (Syngnathus acus, S. rostellatus andS. typhle) have fully enclosed brood pouches on their tails. Males of the former species receive eggs from one female while males of the genusSyngnathus receive partial clutches from several females. Sex ratios of adults on the site differed from equal to male-biased to female-biased, according to species.S. typhle were most numerous and were resighted most often. They were present throughout the breeding season whereas there were temporal shifts in the presence of the other species on the meadow and in some sex ratios. Most species occurred in the deeper, denser part of the meadow but there was some habitat separation by species and sex. All species tended to stay low in the eelgrass, primarily coming up above the eelgrass to display and mate. No species showed site fidelity either to a home range or to the meadow, withE. aequoreus adults spending least time on the meadow. Sexual size dimorphism differed: males were larger inS. rostellatus, the same size inS acus and smaller in the other species. Although the species overlap in habitat requirements and breeding season, the only observed interspecific interactions were abortive courtships betweenSyngnathus species.     

Labiatae Novae Iranicae

Four new species are described:Lavandula sublepidota, from S. Iran (related toL. coronopifolia),Phlomis pachyphylla from S. Iran, Prov. Fars (nearPh. polioxantha),Satureia isophylla from N. Iran, Prov. Mazanderan (close toS. mutica andS. intermedia), andThymbra neurophylla from Iraqi Kurdistan (distinct forth species of the genus).

Florae Iranicae praecursores 1–4.     

Phylogenetic relationships inSecale (Poaceae): An isozymatic study

The genetic frequencies of 9 isozyme loci have been estimated in 23 samples of 4 species ofSecale by means of starch gel electrophoresis. The populations ofS. silvestre andS. vavilovii were monomorphic and uniform within each species, those ofS. montanum andS. cereale were polymorphic for most of the isozyme loci. On the basis of isozyme patterns as well as allelic and genotypic frequencies of isozyme loci,S. silvestre can be distinguished fromS. vavilovii, and both fromS. cereale andS. montanum; but there is no clear differentiation between the two latter species. Clusters constructed from genetic distances separateS. silvestre andS. vavilovii, whereasS. cereale andS. montanum were grouped together. The isozymatic data presented here, along with cytogenetic and life habit data, agree with the generally admitted existence of 4 species inSecale, and support the relationships suggested byKhush & Stebbins (1961).     

Temporal Fluctuations and Settlement Patterns of Native and Lessepsian Herbivorous Fishes on the Lebanese Coast (Eastern Mediterranean)

We provide here the first information on the abundance, settlement patterns and microhabitat use of settlers of two Lessepsian siganid species, Siganus rivulatus and S. luridus, in comparison with the two main native herbivores, Sparisoma cretense (Scaridae) and Sarpa salpa (Sparidae). S. rivulatus was the most abundant species (72%), followed by S. cretense (20%) and S. luridus (8%), whereas S. salpa was rare (<1%). A clear pattern of settlement could be established for S. rivulatus and S. cretense, with similar timing in 1999 and 2000. S. cretense settled in schools late June, while S. rivulatus settled mid-July. A few solitary settlers of S. luridus were observed in July and August, but none of S. salpa. All these herbivorous fish species settled in protected shallow areas offering hard substrates and algal communities. S. rivulatus was the most tolerant and adaptable species, able to settle on a large range of substrates and habitats, including rock pools, muddy harbours and sea grass beds. In the eastern Mediterranean Sea, S. rivulatus might have benefited from a release of competition pressure due to the low diversity and abundance of native herbivores. It has probably replaced S. salpa on the coast of Lebanon, being more competitive than the native sparid.     

Localized hybridization betweenSaxifraga aizoides andS. mutata (Saxifragaceae): Reproductive ecology ofS. ×hausmannii and implications for conservation

The roles of hybridization and of introgression as potential threats to small native populations are current topics of interest both for evolutionary and conservation biologists. Two factors are mainly involved in the threat to natural populations through hybridization: demographic swamping and genetic assimilation. At prealpine locations, twoSaxifraga species with very different growth habits,S. aizoides andS. mutata, form a hybrid,S. ×hausmannii. Investigation of meiosis and crossing experiments revealed regular pairing of the 26 chromosomes and development of viable seeds in the hybrid. Analysis of hybrid indices, GPI allozymes, germination experiments and seed sizes showed an intermediate position ofS. ×hausmannii between its parental species.Saxifraga aizoides andS. mutata were separated by only weak hybridization barriers. Introgression occurred mostly in direction ofS. aizoides, although to a small amount. There is no actual threat to small, prealpine populations ofS. aizoides andS. mutata through interspecific gene flow because hybridization is localized, resulting from different flowering phenologies of the parental species and from the narrow habitat requirements ofS. ×hausmannii, which are similar to those ofS. aizoides. The major threat to local, prealpine populations ofS. aizoides andS. mutata is the loss of landscape dynamics. Both species need open erosion slopes for successful recruitment.     

New species of Selaginella (Selaginellaceae) from the Guayana Highland of Venezuela

Three new species of Selaginella are described from the Guayana Highland of Venezuela: S. cardiophylla, S. hemicardia and S. pruskiana. They are illustrated and the relationships of each are discussed. Another species, provisionally determined as S. terezoana, is reported for the first time from Guyana.     

Competitive interactions between the rotifer Synchaeta oblonga and the cladoceran Scapholeberis kingi Sars

Competition experiments showed that the small cladoceran Scapholeberis kingi rapidly excluded the rotifer Synchaeta oblonga from mixed-species cultures, but was itself unaffected by the presence of S. oblonga. Short-term experiments testing the effect of S. kingi on the survivorship and reproduction of S. oblonga showed that the former imposed a high mortality on the latter, even though shared food resources were abundant. These results indicate that adult S. kingi mechanically interferes with S. oblonga either by ingesting, or by rejecting in a damaged condition, individuals swept into its branchial chamber. In contrast to many other small species of cladocerans, and like large species of Daphnia, S. kingi has the potential to markedly suppress populations of some rotifer species through a combination of interference and exploitative competition.     

Relationships betweenOryza species (Poaceae) based on 5S DNA sequences

Relationships between 9Oryza species, covering 6 different genomes, have been studied using hybridization and nucleotide sequence information from the5S Dna locus. Four to five units of the major size class of 5S DNA in each species, 55 units in all, were cloned and sequenced. Both hybridization and sequence data confirmed the basic differences between the A and B, C, D genome species suggested by morphological and cytological data. The 5S DNA units of the A genome species were very similar, as were the ones from the B, C, and D genome-containing species. The 5S DNA ofO. australiensis (E genome) grouped with the B, C, D cluster, while the units ofO. brachyantha (F genome) were quite different and grouped away from all other species. 5S DNA units fromO. minuta, O. latifolia, O. australiensis, andO. brachyantha hybridized strongly, and preferentially, to the genomic DNA from which the units were isolated and hence could be useful as species/genome specific probes. The 5S DNA units fromO. sativa, O. nivara, andO. rufipogon provided A genome-specific probes as they hybridized preferentially to A genome DNA. The units fromO. punctata andO. officinalis displayed weaker preferential hybridization toO. punctata DNA, possibly reflecting their shared genome (C genome).     

The genus Setulipes (Marasmiaceae) in Madagascar and the Mascarenes, including a key to other African taxa

The authors report first records for the genus Setulipes in Madagascar, with the presence of Setulipes cf. hakgalensis and two new species, Setulipes funaliformis and S. moreaui, as well as a new species from Mauritius: S. mauritiensis. A key to these taxa, as well as to other African species, is supplied.     

Characterization of Charr Chromosomes Using Fluorescence in Situ Hybridization

The chromosomal locations of several families of tandem repetitive DNA sequences and the 5S rDNA were determined using fluorescence in situ hybridization (FISH) in the five North American charr species: Salvelinus namaycush, S. fontinalis, S. alpinus, S. malma, and S. confluentus. The pattern of hybridization of three centromeric repetitive sequences previously isolated from S. namaycush and S. alpinus was unique in each species. Dual-color FISH experiments showed that in several species many of the centromeres had the EcoRI-DraI family in addition to either the AluI-RsaI type A or type B families. The EcoRI-DraI family which was found only at the centromeres of acrocentric chromosomes in S. namaycush, S. fontinalis and S. malma was also found at centromeres of selected metacentrics in S. alpinus (one pair) and S. confluentus (four pairs) whose chromosomes have undergone additional centric fusions compared to the other species. The locations of 5S rDNA sequences were different in each species except for the two most closely related (S. alpinus and S. malma). Two whole-arm chromosome paint probes, one specific for the short and the other for the long arm of the lake charr sex chromosomes, hybridize to the same chromosome pair in all species. Results with other paint probes suggest that independent centric fusions have occurred in S. alpinus and S. confluentus which is consistent with the phylogenetic tree obtained previously for Salvelinus with cytogenetic and DNA data.