Two new species of <Emphasis Type="Italic">Henriettea</Emphasis> (Melastomataceae,Henrietteeae) for the flora of the Greater Antilles

Two new species of Melastomataceae are described and illustrated: Henriettea sierrae from the mountains of eastern Cuba, and Henriettea multigemma from the Sierra de Bahoruco in the Dominican Republic, Hispaniola. Both species belong to the complex of squamous Henriettea species endemic to the Greater Antilles. Henriettea sierrae is distinguished by its ciliate leaves, foliose bracteoles at the base of the flowers, and lanceolate petals with lateral teeth in their apical third. Henriettea multigemma is distinguished by its fascicles of numerous flowers that are borne of suberose protuberances formed by multiple flower buds in the leafless nodes of the stems, and by the presence of leaves with apical domatia.     

A new species of Bursera (Burseraceae) from Cuba

A revision of Bursera in the Greater Antilles has revealed the first new species of the genus to be described from the Caribbean in almost 45 years. Bursera gibarensis is known only from coastal scrub on dogtooth limestone near Gibara in Holguín Province.     

A revision of the genus Oxytheca Nutt. (Polygonaceae)

The genusOxytheca of western North America and temperate South America consists of seven species which are keyed, described, discussed, illustrated, and mapped. They are divided among sect.Oxytheca, sect.Acanthoscyphus stat. & comb. nov., and sect.Neoxytheca sect. nov.Oxytheca dendroidea subsp.chilensis is given as a new combination, whileO. parishii var.cienegensis andO. parishii var.goodmaniana are described as new. The history and relationships of the genus are discussed. It is retained as distinct fromEriogonum and is thought to have arisen from the larger genus nearE. spergulinum, E. parishii, andE. apiculatum in subgenusGanysma. Cytological data indicatedn= 20.     

A revision of Vernonia series Buddleiifoliae (Compositae: Vernonieae)

SeriesBuddleiifoliae of the genusVernonia of southeastern South America consists of 18 species which are keyed, described, discussed and mapped.Vernonia goiasensis is proposed as a new name, whileV. wasshausenii andV. monocephala subsp.irwinii are described as new taxa, and V.asteriflora subsp.kuntzei is presented as a new combination.     

Notes on Collybia V. Gymnopus section Levipedes in tropical South America,with comments on Collybia

Five species of Gymnopus section Levipedes are reported for tropical South America. Two of these, Gymnopus macropus and G. nubicola, are newly described. Collybia laccata is considered synonymous with G. mucubajiensis comb. nov. now known from Andean Ecuador; both were originally described from the Venezuelan páramo. Gymnopus alkalivirens and G. semihirtipes are compared to G. mucubajiensis. Gymnopus spongiosus, previously known from the eastern United States, is newly reported from Colombian Quercus forests and is proposed as a new combination. Gymnopus dryophilus is, at present, not known from tropical South America, but extralimital material from nearby Costa Rica is described for comparison. No known species of Collybia s.str. have been identified from tropical South America.     

A new species of Maxillaria (Orchidaceae) from Costa Rica

Maxillaria suaveolens Barringer from the Gulfo Dolce region of Costa Rica is described and illustrated.     

Mycopteris,a new neotropical genus of grammitid ferns (Polypodiaceae)

Mycopteris, a new genus of grammitid ferns, is described and combinations are made for the species that belong to it. Mycopteris is diagnosed by castaneous rhizome scales with turgid cells, usually pectinate laminae, blackish petioles and rachises, blackish pinna costae and veins, reddish setae, cretaceous hydathodes, glabrous sporangia, and the presence of Acrospermum ascomes. It is entirely neotropical, ranging from Mexico east into the West Indies and south to Bolivia. Mycopteris is one of two genera of grammitid ferns that are consistently associated with Acrospermum, an epibiotic ascomycete that produces black clavate fruiting bodies. Seventeen species of Mycopteris are recognized here, including one new species (M. longipilosa) and one elevated from the rank of variety to species (M. costaricensis). The following additional combinations are made here: M. alsopteris, M. amphidasyon, M. attenuatissima, M. cretata, M. grata, M. leucolepis, M. leucostica, M. longicaulis, M. pirrensis, M. praeceps, M. semihirsuta, M. steyermarkii, M. subtilis, M. taxifolia, and M. zeledoniana. Lectotypes are chosen for Ctenopteris leucosticta, Polypodium amphidasyon, and Polypodium pectinatum var. hispidum. For each accepted species, full synonymy and geographical range are provided. Taxonomic discussion is provided for species not widely recognized in previous treatments.     

Characterization of bio-related vanadium and zinc complexes containing tetradentate dithiolate-disulfide, -diamine and -amine-amide ligands

The reaction of [VCl₃(PMe₂Ph)₃] _{with HSS′S′SH (where the HS are thiophenolate and the S′ thioether functions, respectively), H2–1, yields [VCl(μ-SS′S′S)]2 (3) with one of the thiolate groups of each of the two ligands in the bridging mode. Reaction of Na2–1 with [VOCl2(thf)2] leads to a polymeric product of composition [VO(SS′S′S)]x (4). The products obtained from the reaction between [VOCl2(thf)2] and NaSNNSNa, Na2–2, (S is thiophenolate, N the amine function) depend on subtle changes in the diamine backbone of this ligand: If the amine functions are linked by -CH2CH2– (2a), the tetranuclear V^IV complex [V(SNNS)μ-O]4 (5) is formed alongside the V^III complex [VCl(SNNS)]. If the backbone is -CH(Me)CH(Me)- (2b), [VO(SNNS)] (7) and the dinuclear, asymmetrically oxo-bridged V^IV complex [{(SNN ^– S)(thf)V}μ-O{V(SNN ^– S)}] (8) are obtained. In 8, one amine of each of the two ligands is deprotonated to the amide group. In either case, the complexation is accompanied by oxidation of the thiolates to disulfides, leading to the generation of teraazatetrathio-cycloeicosanes (6a/b). Compounds 5 and 8·2THF have been structurally characterized by X-ray analyses. The connectivities have further been established for 3·2CH2Cl2 and for 6b, which exhibits the same conformation as formally characterized 6a. The cluster compound 5 is stabilized by an extended intramolecular N-H...O and N-H...S) hydrogen-bonding network. In 7·2THF, one of the THFs of crystallization is hydrogen-bonded to the NH of the penta-coordinated {VO(SNN ^– S)} moiety; further, there is an intramolecular hydrogen bond between one of the thiolates of this tetragonal-pyramidal half of the molecule and the NH of the octahedral {VO(SNN ^– S)thf} half. The generation of the ligand 2b from its precursor compound, the zinc complex [Zn(SNNS)] (9) leads to the structural characterization of 9·CH3OH with a large SZnS bite angle and a strong hydrogen bond between the methanolic OH and one of the thiolate sulfurs. The relevance of these compounds in biological systems is discussed.}     

New species of Gustavia (Lecythidaceae) from Panama,Colombia, and Venezuela

Gustavia monocaulis from east-central Panama,G. sessilis from the Chocó of Colombia, andG. flagellata, including two varieties (var.flagellata and var.costata) from the north-central coast of Venezuela, are described and their relationships with otherGustavia species discussed.     

New species in Adiantum and Pteris (Pteridaceae) from the Andes

We describe, discuss, and illustrate four new species, one inAdiantum (A. capillatum A. R. Sm. &; Prado, from Ecuador) and three species inPteris (P. lellingeri A. R. Sm. &; Prado, from Bolivia;P. venezuelensis A. R. Sm. &; Prado, from Venezuela; andP. websteri A. R. Sm. &; Prado, from Ecuador, Colombia, and Bolivia).     

Different non-host resistance responses of two rice subspecies,japonica and indica,to Puccinia striiformis f. sp. tritici

Key message

Japonica and indica have different non-host resistance (NHR) abilities to Puccinia striiformis f. sp. tritici ( Pst ), and hydrogen peroxide (H ₂ O ₂ ) has a positive function in NHR to japonica against Pst.

Abstract

Non-host interactions between Puccinia striiformis f. sp. tritici (Pst) and two rice subspecies were characterized using 23 rice varieties, including 11 japonica and 12 indica. Results showed that the infected fungal structures were easily produced in the leaves of indica, whereas only several substomatal vesicles and primary infection hyphae were observed in the leaves of japonica. This result indicated that indica is less resistant or more susceptible to Pst than japonica. Hydrogen peroxide accumulated in the initial phase of japonica–Pst interaction but not in indica–Pst interaction. A set of reactive oxygen species (ROS)-related genes was also induced in response to Pst infection, suggesting that ROS activation is one of the major mechanisms of non-host resistance of rice to Pst.     

New names,combinations, and lectotypifications in Heterotheca (Compositae: Astereae)

The following new names and combinations are proposed:Heterotheca barbata (Rydb.) Semple,H. horrida subsp.cinerascens (S. F. Blake) Semple,H. fulcrata vararizonica Semple,H. fulcrata var.senilis (Wooton & Standley) Semple,H. oregona var.compacta (Keck) Semple,H. oregona var.rudis (Greene) Semple,H. oregona var.scaberrima (A. Gray) Semple,H. pumila (Greene) Semple,H. villosa var.pedunculata (Greene) V. Harms ex Semple, andH. zionensis Semple. The following chromosome numbers are reported for the first time:H. fulcrata var.arizonica, 2n=9 _II ;H. horrida subsp.cinerascens, 2n=18 _II ;H. pumila, 2n=9 _II ,2n=18 _II ;H. zionensis, 2n=9 _II .     

Nymphaea tetragona and Nymphaea leibergii (Nymphaeaceae): two species of diminutive water-lilies in North America

Although all past floras of northern North America have recognized only one species of diminutive water-lily, actually two distinct species occur in the region. The circumboreal Nymphaea tetragona Georgi is largely confined to the northwestern part of the continent, extending as far east as Manitoba and occurring in the contiguous United States only in northwest Washington. A second species, N. leibergii Morong, is restricted to, but widely distributed in, northern North America, though it is absent from the extreme northwest. The two species are distinguishable from each other by several floral and foliar characters and the two species form a section, Nymphaea subg. Nymphaea sects. Chamaenymphaea, stat: nov. This is distinguished from the two other sections of subg. Nymphaea in a key, and Nymphaea subg. Nymphaea sect. Xanthantha, stat. nov., is proposed. Sect. Chamaenymphaea is described for North America, synonymy and nomenclature for both species are discussed, and a key including N. odorata Aiton is presented. A lectotype is provided for N. leibergii and the typification of N. tetragona is examined.     

A new species ofAphidius [Hymenoptera] attacking the pea aphid,Acyrthosiphon pisum

Aphidius staryi Chen & Luhman n. sp. is described. The species was collected and introduced into California from Israel and Turkey byD. González. The new species is morphologically most similar toAphidius smithi, and keys toEady's urticae group.     

Di- and polynuclear silver(I) saccharinate complexes of tertiary diphosphane ligands: synthesis, structures, in vitro DNA binding, and antibacterial and anticancer properties

A series of new silver(I) saccharinate (sac) complexes, [Ag₂(sac)₂(μ-dppm)H₂O]·H₂O (1), {[Ag₂(μ-sac)₂(μ-dppe)]·3H₂O·CH₂Cl₂} _n (2), [Ag₂(μ-sac)₂(μ-dppp)] _n (3), and [Ag(sac)(μ-dppb)] _n (4) [dppm is 1,1-bis(diphenylphosphino)methane, dppe is 1,2-bis(diphenylphosphino)ethane, dppp is 1,3-bis(diphenylphosphino)propane, and dppb is 1,4-bis(diphenylphosphino)butane], have been synthesized and characterized by C, H, N elemental analysis, IR spectroscopy, ¹H NMR, ¹³C NMR, and ³¹P NMR spectroscopy, electrospray ionization mass spectrometry, and thermogravimetry–differential thermal analysis. Single-crystal X-ray studies show that the diphosphanes act as bridging ligands to yield a dinuclear complex (1) and one-dimensional coordination polymers (2 and 4), whereas the sac ligand adopts a μ₂-N/O bridging mode in 2, and is N-coordinated in 1 and 4. The interaction of the silver(I) complexes with fish sperm DNA was investigated using UV–vis spectroscopy, fluorescence spectroscopy, and agarose gel electrophoresis. The binding studies indicate that the silver(I) complexes can interact with fish sperm DNA through intercalation, and complexes 1 and 3 have the highest binding affinity. The gel electrophoresis assay further confirms the binding of the complexes with the pBR322 plasmid DNA. The minimum inhibitory concentrations of the complexes indicate that complex 1 exhibits very high antibacterial activity against standard bacterial strains of Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus, being much higher than those of AgNO₃, silver sulfadiazine, ciprofloxacin, and gentamicin. Moreover, complexes 1–3 exhibit very high cytotoxic activity against A549 and MCF-7 cancer cell lines, compared with AgNO₃ and cisplatin. The bacterial and cell growth inhibitions of the silver(I) complexes are closely related to their DNA binding affinities.     

A new species of eleocharis (Cyperaceae) from The West Indies

Eleocharis liogieri, described as new from Santo Domingo and the Lesser Antilles, belongs to sect.Tenuissimae in the Cyperaceae.