Trisetum spicatum (L.)Richt. in northern Borneo

A new subspecies ofTrisetum spicatum (L.)Richt. has been described from Borneo.     

Trisetum curvisetum (Poaceae: Aveneae), a new species from Mexico

Trisetum curvisetum is a new species from high Sierra Madre Oriental in Nuevo León, Mexico. Its soft rather than liquid endosperm is new for the genus, and its lemma awn is thin and flexuous, easily distinguishable from that of other North AmericanTrisetum.     

Effect of Trisetum flavescens P.B. on calcium and phosphorus metabolism in rats. Experimental evidence for the principle actively affecting phospho-calcium homeostasis.

After reviewing the literature on the vitamin D3-like activity of certain plants [Solanum malacoxylon, Cestrum diurnum and Trisetum flavescens], the authors present results of experiments in which dried Trisetum flavescens was administered perorally to rats. The addition of 2.5% dried Trisetum flavescens to the standard laboratory diet caused a drop in blood phosphate levels and a simultaneous marked increase in the calcium and phosphorus content of bones of the experimental animals. The mechanism of the action of Trisetum flavescens on phosphocalcium metabolism is discussed.     

Occurrence of cholecalciferol in the calcinogenic plant Trisetum flavescens.

The grass Trisetum flavescens causes severe calcification of soft tissues upon ingestion by various species, which has been ascribed by others to a 1,25(OH)₂ vitamin D₃-like activity.By a special purification procedure involving high pressure liquid chromatography and continuous biological testing the active principle was purified. By means of $\text{GC}\text{MS}$ it was identified as cholecalciferol, being present in a concentration of about 0.1 ppm in the lyophylized plant dry matter. 1,25(OH)₂ vitamin D₃ or other metabolites of vitamin D₃ were not present. Since such low concentrations could hardly explain the calcinosis observed, a more active “bound form” of vitamin D₃ may be present in Trisetum flavescens.     

Effect of long-term cutting versus abandonment on the vegetation of a mountain hay meadow (Polygono-Trisetion) in Central Europe

The aim of this study was to identify changes in the plant species richness, diversity and composition of a mountain hay meadow (alliance Polygono bistortae-Trisetion flavescentis) after abandonment in comparison with a control cut once per year. The experiment was carried out from 1999 to 2008 in a mountain hay meadow in the Bukovec nature reserve in the north-eastern part of the Jizera Mountains (Jizerské hory, Góry Izerskie, Isergebirge), Czech Republic.The number of vascular plants species with cover greater than or equal to 1% remained almost the same throughout the study period; however, the total number of vascular plants was higher in the cut treatment after the first four years of the study. The cover of Festuca rubra, Agrostis capillaris, Anthoxanthum odoratum, Briza media and Trifolium repens was positively affected by cutting. On the other hand, the cover of Cirsium heterophyllum, Geranium sylvaticum, Hypericum maculatum, Trisetum flavescens and Luzula luzuloides was higher on the abandoned treatment plots.The main effect of the abandonment on plant species composition was the shift in cover of the dominant species. Despite ten years of contrasting management, changes in the vegetation were relatively small with no shift to a different plant community. Therefore the cutting regime combined with several years of no management may be a suitable management strategy for the maintenance of Polygono-Trisetion grasslands and will not be detrimental to the preservation of the target vegetation.     

Distribution and pollination services of wild bees and hoverflies along an altitudinal gradient in mountain hay meadows

Extensively managed and flower‐rich mountain hay meadows, hotspots of Europe''s biodiversity, are subject to environmental and climatic gradients linked to altitude. While the shift of pollinators from bee‐ to fly‐dominated communities with increasing elevation across vegetation zones is well established, the effect of highland altitudinal gradients on the community structure of pollinators within a specific habitat is poorly understood. We assessed wild bee and hoverfly communities, and their pollination service to three plant species common in mountain hay meadows, in eighteen extensively managed yellow oat grasslands (Trisetum flavescens) with an altitudinal gradient spanning approx. 300 m. Species richness and abundance of pollinators increased with elevation, but no shift between hoverflies and wild bees (mainly bumblebees) occurred. Seedset of the woodland cranesbill (Geranium sylvaticum) increased with hoverfly abundance, and seedset of the marsh thistle (Cirsium palustre) increased with wild bee abundance. Black rampion (Phyteuma nigrum) showed no significant response. The assignment of specific pollinator communities, and their response to altitude in highlands, to different plant species underlines the importance of wild bees and hoverflies as pollinators in extensive grassland systems.     

Chromosome numbers of Costa Rican grasses

Chromosome counts are presented for 217 species of 103 genera of grasses from Costa Rica. Four of the genera and 90 of the species are reported for the first time. In addition, 26 counts differ from previous records for the same taxon. The generaGynerium, Lithachne, Luziola, andThrasya were heretofore unknown cytologically. First counts are also given for the following species:Agrostis bacillata, A. pittieri, A. sub patens, Andropogon angustatus, A. bicornis, A. virgatus, Aristida capillacea, A. jorullensis, Arundinella berteroniana, A. deppeana, Axonopus aureus, A. capillaris, A. chrysoblepharis, Bouteloua americana, B. disticha, Bromus exaltatus, Calamagrostis intermedia, C. nuda, C. pittieri, Chusquea lehmannii, C. tonduzii, Cinna poaeformis, Deschampsia pringlei, Digitaria panicea, Echinochloa polystachya, Echinolaena gracilis, Eragrostis simplicijlora, Eriochloa distachya, E. polystachya, Eriochrysis cayennensis, Festuca dolichophylla, Gymnopogon fastigiatus, Gynerium sagittatum, Hymenachne amplexicaulis, Imperata contracta, Isachne polygonoides, Ischaemum latijolium, Lithachne pauciflora, Luziola fragilis, Manisuris aurita, Panicum aquaticum, P. arundinariae, P. boliviense, P. cordovense, P. grande, P. haenkeanum, P. milleflorum, P. parviglume, P. pilosum, P. polygonatum, P. rudgei, P. stenodes, P. trichanthum, P. trichoides, P. viscidellum, Paspalum candidum, P. centrale, P. decumbens, P. fasciculatum, P. jimenezii, P. microstachyum, P. multicaule, P. nutans, P. parviflorum, P. pilosum, P. prostratum, P. pumilum, P. reclinatum, P. saccharoides, P. scabrum, P. serratum, P. squamulatum, P. standleyi, Pennisetum bambusiforme, P. distachyum, Pereilema beyrichianum, Pharus parvifolius, Sacciolepis myuros, Schizachyrium condensatum, Sorghastrum incompletum, Sporobolus ciliatus, S. purpurascens, Streptochaeta sodiroana, Thrasya gracilis, T. petrosa, T. robusta, Trisetum pringlei, T. tonduzii, Uniola pittieri, and Zeugites pittieri. In addition, the following counts are different from previous records for the same taxon:Aegopogon cenchroides, Axonopus poiophyllus, Bouteloua media, Brachiaria plantaginea, Chusquea subtessellata, Digitaria adscendens, Homolepis aturensis, Hymenachne donacifolia, Ichnanthus axillaris, I. pallens, I. tenuis, Ischaemum ciliare, Ixophorus unisetus, Oplismenus burmannii, O. hirtellus, Panicum geminatum, P. glutinosum, P. mertensii, P. parvifolium, P. sellowii, Paspalum convexum, Pennisetum nervosum, P. setosum, Polypogon elongalus, Raddia costaricensis, Schizachyrium hirtijlorum.     

Vegetation on avalanche paths in the alps

Vegetation pattern on avalanche paths in the Nordkette Mountains near Innsbruck (Tyrol, Austria) was studied using transect sampling. The plant communities represent a gradient from alpine grassland (Seslerio-Caricetum sempervirentis, via grassland with Trisetum distichophyllum) and nutrient-poor grassland (Carlino-Caricetum sempervirentis) to an avalanche grassland proper. Along this gradient disturbance decreases from higher to lower elevations. The topography of the avalanche path suggests a gradient from the central zone to the edge of the path, although a floristic zonation or grouping of species across the path cannot be detected. Disturbance and local topography are the dominant factors for the vegetation pattern on the avalanche paths investigated.Abbreviations DCA= detrended correspondence analysis     

Genetic similarity among Trifolium species based on isozyme banding pattern

The study deals with similarity among 25 species of the genus Trifolium represented by 134 accessions. Clustering of the species based on isozyme banding pattern of five enzymes revealed that T. repens was distinctly different from other species. T. repens and T. retusum formed independent clusters. The group of species comprising of T. pratense, T. cherleri, T. spumosum, T. subterraneum, T. resupinatum, T. alexandrinum, T. echinatum, T. constantinopolitanum and T. tembense exhibited considerable similarity to the second cluster. This group joined another group of five species, i.e. T. nigrescens, T. glomeratum, T. apertum, T. alpestre and T. hybridum with nearly 50% similarity. T. purpureum, T. hirtum, T. campestre, T. incarnatum, and T. argutum grouped separately. There was no marked difference for banding pattern among T. alexandrinum genotypes. T. alexandrinum showed close affinity with T. subterraneum and T. resupinatum. T. lappaceum, T. diffusum, T. campestre, T. incarnatum and T. argutum showed only 44.8% similarity with other Trifolium species. Grouping together of accessions belonging to individual species indicated that incompatibility among species under study had restricted interspecific hybridization. Species belonging to subgenus Lotoidea clustered with species of subgenus Trifolium. Chonosemium species T. campestre formed one cluster with two Trifolium species T. hirtum and T. incarnatum. T. nigrescens was placed quite apart from the T. repens.     

Tylenchulus graminis n. sp. and T. palustris n. sp. (Tylenchulidae), from Native Flora of Florida,with Notes on T. semipenetrans and T. furcus

Tylenchulus graminis n. sp. and T. palustris n. sp. are described and illustrated from broomsedge (Andropogon virginicus L.) and pop ash (Fraxinus caroliniana Mill.), respectively. T. graminis resembles T. furcus in having a distinct anus, but T. graminis second-stage juveniles (J2) do not have a bifid tail. T. semipenetrans does not have a perceptible anus. The mature female of T. graminis has a mucronate pointed terminus while T. semipenetrans has a smooth and round terminus. T. graminis males have wider stylet knobs and basal bulb and a longer tail than T. semipenetrans males. T. graminis J2 have a longer posterior body portion (without large fat globules) than T. semipenetrans J2. T. palustris resembles T. semipenetrans in having an undetectable anus but differs by the short and conoid mature female postvulval section. The male of T. palustris has larger stylet knobs and basal bulb than those of T. semipenetrans and a bluntly rounded tail terminus, which is tapered in T. semipenetrans. T. palustris differs from T. furcus and T. graminis in having an undetectable anus, by the conoid postvulval section of mature females, by the shorter and rounded tail of males, and the shorter J2 posterior body section without large fat globules. T. graminis and T. palustris are parasites of indigenous flora of Florida.     

New names and combinations in Trixis (Compositae)

Trixis chiapensis, T. grandibracteata, T. mexicana var.auriculata, T. mexicana var.macradenia, andT. parviflora are described as new, and the combinationsT. californica var.peninsularis, T. michuacana var.longifolia, andT. pringlei var.oligantha are proposed. The application of the namesT. inula andT. michuacana is discussed.     

Relatively Recent Evolution of Pelage Coloration in Colobinae: Phylogeny and Phylogeography of Three Closely Related Langur Species

To understand the evolutionary processes leading to the diversity of Asian colobines, we report here on a phylogenetic, phylogeographical and population genetic analysis of three closely related langurs, Trachypithecus francoisi, T. poliocephalus and T. leucocephalus, which are all characterized by different pelage coloration predominantly on the head and shoulders. Therefore, we sequenced a 395 bp long fragment of the mitochondrial control region from 178 T. francoisi, 54 T. leucocephalus and 19 T. poliocephalus individuals, representing all extant populations of these three species. We found 29 haplotypes in T. francoisi, 12 haplotypes in T. leucocephalus and three haplotypes in T. poliocephalus. T. leucocephalus and T. poliocephalus form monophyletic clades, which are both nested within T. francoisi, and diverged from T. francoisi recently, 0.46-0.27 (T. leucocephalus) and 0.50-0.25 million years ago (T. poliocephalus). Thus, T. francoisi appears as a polyphyletic group, while T. leucocephalus and T. poliocephalus are most likely independent descendents of T. francoisi that are both physically separated from T. francoisi populations by rivers, open sea or larger habitat gaps. Since T. francoisi populations show no variability in pelage coloration, pelage coloration in T. leucocephalus and T. poliocephalus is most likely the result of new genetic mutations after the split from T. francoisi and not of the fixation of different characters derived from an ancestral polymorphism. This case study highlights that morphological changes for example in pelage coloration can occur in isolated populations in relatively short time periods and it provides a solid basis for studies in related species. Nevertheless, to fully understand the evolutionary history of these three langur species, nuclear loci should be investigated as well.     

Population Response to Temperature in the Subfamily Tylenchorhynchinae

The effects of temperature on population development of 11 species of stunt nematodes in the subfamily Tylenchorhynchinae were compared on red clover or Kentucky bluegrass in constant-temperature tanks at 5-degree intervals from 10 to 35 C. The optimum temperature for population increase on red clover in 90 days was 30 C for Tylenchorhynchus agri, T. nudus, T. martini, and T. clarus, 25 C for T. sylvaticus and T. dubius, and 20 C for T. canalis, Merlinius brevidens, and Quinisulcius capitatus. The optimum was 30 C for T. robustoides and 25 C for T. maximus on Kentucky bluegrass. The temperature range for population increase was 20-35 C for T. agri, T. nudus, T. martini, and T. clarus, 20-30 C for T. sylvaticus and T. robustoides, 15-25 C for T. maximus, 10-25 C for T. dubius, and 10-20 C for M. brevidens and Q. capitatus. T. canalis increased only at 20 C. All species were recovered in numbers near their inoculum level at 10 C. There was no survival of T. sylvaticus, T. dubius, T. canalis, T. robustoides, T. maximus, M. brevidens, and Q. capitatus at 35 C, or of the last three of these species at 30 C. Temperature had no effect on sex ratio in final populations. Population increase was greatest in T. martini and least in T. canalis.     

Studies on California ants: a review of the genus Temnothorax (Hymenoptera,Formicidae)

The following ten new species of the ant genus Temnothorax are described and illustrated: T. anaphalantus (California, Baja California), T. arboreus (California), T. caguatan (Oregon, California, Baja California), T. morongo (California, Baja California), T. myrmiciformis (California, Baja California), T. nuwuvi (Nevada), T. paiute (California, Nevada), T. pseudandrei (Arizona, California), T. quasimodo (California) and T. wardi (California). A key to workers of the twenty-two Temnothorax species known or expected to occur in California is provided.     

Nuclear DNA content variation within the genusTaraxacum (Asteraceae)

Nuclear DNA content was estimated using flow cytometry in 13 sections represented by 18 species of the genusTaraxacum using propidium iodide as the DNA stain. Investigated plants represented diploid, triploid and tetraploid species from sections considered both primitive and advanced, i.e.,T. sect.Dioszegia, Piesis, Glacialia, Mongolica, Scariosa, Obovata, T. pyrenaicum group,T. sect.Coronata, Palustria, Taraxacum (=Crocea),Kashmirana, Ruderalia andErythrosperma. Estimated nuclear 2C DNA content ranged from 1.74 pg in diploidT. linearisquameum (T. sect.Ruderalia) to 6.91 pg in tetraploidT. albidum (T. sect.Mongolica), demonstrating 3.97-fold variation. The lowest monoploid genome size 1C_x=0.87 pg was recorded inT. linearisquameum (T. sect.Ruderalia) together withT. brachyglossum (T. sect.Erythrosperma), and the highest one (1.73 pg) was recorded inT. albidum (T. sect.Mongolica), giving a 1.99-fold difference in the genus. No significant differences in genome size were observed withinT. sect.Ruderalia, similarly no intraspecific variation was observed inT. paludosum (T. sect.Palustria) andT. serotinum (T. sect.Dioszegia). These results indicate a high intraspecific stability of the trait. Preliminary comparisons of genome size in species/sections considered to be close relatives were made. These data give tentative additional evidence for the close phylogenetic relationship between sectionsPalustria andPiesis and against the close relationship between sectionsPiesis andDioszegia.     

Floral morphology and systematics of the genus Thottea Rottb. (Aristolochiaceae) from the Western Ghats, India

The medicinal genus Thottea (Aristolochiaceae) is represented in the Western Ghats, India, by eight species, seven of which are endemic to this region. In the present study, diversity in floral structure and organization of these eight species was analyzed from a systematic perspective. Floral morphology was thoroughly studied and discussed with emphasis on 16 qualitative and 11 quantitative characters. Statistical tools such as UPGMA cluster analysis, PCoA, PCA, and one-way ANOVA were used for elucidating species boundaries and inter-relationships. Significance of the selected qualitative and quantitative characters for species level systematics was revealed by the PCA and one-way ANOVA. Based on the nature of sepals (free/fused), two species groups were identified (first group with T. duchartrei and T. idukkiana, and the second group with the remaining six species). By considering the number and arrangement of stamens, yet another species grouping was proposed (one with T. abrahamii and T. dinghoui, and the other with the remaining six species). The UPGMA phenogram and the PCoA scatter plot clearly pointed out the existence of two species groups: the first group with T. abrahamii, T. barberi, T. dinghoui, T. ponmudiana, T. siliquosa, and T. sivarajanii, and the second one with T. duchartrei and T. idukkiana. With regard to the morphometric tools and the taxonomic key, it does not seem possible to distinguish T. abrahamii from T. dinghoui, and T. idukkiana from T. duchartrei.     

Human and Animal Trypanosomes in C?te d'Ivoire Form a Single Breeding Population

Background

Trypanosoma brucei is the causative agent of African Sleeping Sickness in humans and contributes to the related veterinary disease, Nagana. T. brucei is segregated into three subspecies based on host specificity, geography and pathology. T. b. brucei is limited to animals (excluding some primates) throughout sub-Saharan Africa and is non-infective to humans due to trypanolytic factors found in human serum. T. b. gambiense and T. b. rhodesiense are human infective sub-species. T. b. gambiense is the more prevalent human, causing over 97% of human cases. Study of T. b. gambiense is complicated in that there are two distinct groups delineated by genetics and phenotype. The relationships between the two groups and local T. b. brucei are unclear and may have a bearing on the evolution of the human infectivity traits.

Methodology/Principal Findings

A collection of sympatric T. brucei isolates from Côte d’Ivoire, consisting of T. b. brucei and both groups of T. b. gambiense have previously been categorized by isoenzymes, RFLPs and Blood Incubation Infectivity Tests. These samples were further characterized using the group 1 specific marker, TgSGP, and seven microsatellites. The relationships between the T. b. brucei and T. b. gambiense isolates were determined using principal components analysis, neighbor-joining phylogenetics, STRUCTURE, F_ST, Hardy-Weinberg equilibrium and linkage disequilibrium.

Conclusions/Significance

Group 1 T. b. gambiense form a clonal genetic group, distinct from group 2 and T. b. brucei, whereas group 2 T. b. gambiense are genetically indistinguishable from local T. b. brucei. There is strong evidence for mating within and between group 2 T. b. gambiense and T. b. brucei. We found no evidence to support the hypothesis that group 2 T. b. gambiense are hybrids of group 1 and T. b. brucei, suggesting that human infectivity has evolved independently in groups 1 and 2 T. b. gambiense.