17 research outputs found
Dispatch from the field: ecology of ground-web-building spiders with description of a new species (Araneae, Symphytognathidae).
Crassignathadanaugirangensis sp. n. (Araneae: Symphytognathidae) was discovered during a tropical ecology field course held at the Danau Girang Field Centre in Sabah, Malaysia. A taxonomic description and accompanying ecological study were completed as course activities. To assess the ecology of this species, which belongs to the ground-web-building spider community, three habitat types were surveyed: riparian forest, recently inundated riverine forest, and oil palm plantation. Crassignathadanaugirangensis sp. n. is the most abundant ground-web-building spider species in riparian forest; it is rare or absent from the recently inundated forest and was not found in a nearby oil palm plantation. The availability of this taxonomic description may help facilitate the accumulation of data about this species and the role of inundated riverine forest in shaping invertebrate communities
Herbivore benefits from vectoring plant virus through reduction of period of vulnerability to predation
Herbivores can profit from vectoring plant pathogens because the induced defence of plants against pathogens sometimes interferes with the induced defence of plants against herbivores. Plants can also defend themselves indirectly by the action of the natural enemies of the herbivores. It is unknown whether the defence against pathogens induced in the plant also interferes with the indirect defence against herbivores mediated via the third trophic level. We previously showed that infection of plants with Tomato spotted wilt virus (TSWV) increased the developmental rate of and juvenile survival of its vector, the thrips Frankliniella occidentalis. Here, we present the results of a study on the effects of TSWV infections of plants on the effectiveness of three species of natural enemies of F. occidentalis: the predatory mites Neoseiulus cucumeris and Iphiseius degenerans, and the predatory bug Orius laevigatus. The growth rate of thrips larvae was positively affected by the presence of virus in the host plant. Because large larvae are invulnerable to predation by the two species of predatory mites, this resulted in a shorter period of vulnerability to predation for thrips that developed on plants with virus than thrips developing on uninfected plants (4.4 vs. 7.9 days, respectively). Because large thrips larvae are not invulnerable to predation by the predatory bug Orius laevigatus, infection of the plant did not affect the predation risk of thrips larvae from this predator. This is the first demonstration of a negative effect of a plant pathogen on the predation risk of its vector
Segregation of the polyphyletic genus Polyalthia (Annonaceae)
ePoster - P1022The circumscription of the species-rich genus Polyalthia (Annonaceae, with ca. 150 species) has long been recognised to be highly problematic. The genus has functioned as a ‘dustbin group’ for species of unclear affinities due to the absence of clear synapomorphies, resulting in a morphologically heterogeneous species assemblage. Recent molecular phylogenetic analyses have indicated that Polyalthia is highly polyphyletic, with species scattered in multiple clades. The ‘Polyalthia hypoleuca complex,’ including Asian Polyalthia species with columellar-sulcate pollen, was recently segregated to form a new genus, Maasia. A considerably broader taxonomic sampling of Polyalthia species and associated taxa is included in the present phylogenetic analyses, with the objectives of increasing tree resolution and statistical support, hence enabling the recognition of strictly monophyletic genera with clearly defined diagnostic morphological characters. Bayesian and maximum parsimony analyses of chloroplast matK, rbcL and trnL-F DNA sequences consistently gave congruent topologies, with Polyalthia species distributed in five well-supported clades. Based on molecular and morphological data, existing Polyalthia species can be classified into the following five genera: (1) Fenerivia: 10 Madagascan Polyalthia species with columellarsulcate pollen form a well-supported clade distinct from Maasia. The generic name Fenerivia is reinstated for this clade since the type species Fenerivia heteropetala (=Polyalthia heteropetala) is included. (2) Marsypopetalum: five Asian Polyalthia species with thick inwardly-curved inner petals form a well-supported clade with Marsypopetalum pallidum (sister to Trivalvaria) and will be accordingly transferred to Marsypopetalum. (3) Enicosanthum: several Polyalthia species which belong to Polyalthia section Monoon (with a solitary, basal ovule in each ovary) form a wellsupported clade (sister to Neo-uvaria) together with some Enicosanthum species, Woodiellantha sympetala and Cleistopetalum borneense (a synonym of Polyalthia sinclairiana). (4) A new, currently unnamed genus: based on a well-supported clade consisting of several Polyalthia species, sister to Miliusa. (5) Polyalthia sensu stricto: the ‘true’ Polyalthia clade, including the type species, Polyalthia subcordata, and other species in Polyalthia section Polyalthia (with more than two ovules per ovary) as well as species in the small Australian endemic genus Haplostichanthus. The name Haplostichanthus will accordingly be recognized as a synonym of Polyalthia sensu stricto.link_to_OA_fulltextThe 18th International Botanical Congress (IBC2011), Melbourne, Australia, 23-30 July 2011. In Abstract Book of the IBC2011, 2011, p. 664-66
Phylogenetic patterns and genetic diversity of Indian Tinospora species based on chloroplast sequence data and cytochrome P450 polymorphisms
Coscinium fenestratum: a review on phytochemicals and pharmacological properties
Coscinium fenestratum has been used in the traditional medicine, especially in the Ayurvedic method of healing as this plant can be found vastly in the Western Ghats of India. The distribution of this plant is concentrated to the Southeast Asiaincluding Sri Lanka, India, Cambodia, Vietnam, Peninsular Malaysia, Sumatra, West Java, Borneo, Northeast of Thailand and Laos. This review is related to the phytochemicals and pharmacological effects of C. fenestratum. The major chemi- cal constituents present in this plant include alkaloids, flavonoids and steroids. The most important bio-active compound is the berberine, which is the most widely studied plant compound. This plant exerts several pharmacological effects including antidiabetic, anticancer, antibacterial, antimalarial, antioxidant, antihy- pertensive, antiulcer, neuroprotector and wound healing activities. This chapter is supported by in vitro and in vivo studies carried out from the year of 1970 to 2016, which are available from PubMed, ScienceDirect, Google Scholar and Scopus