Da Silva E.L.C.,Grande Rio University |
Viquez C.,Instituto Nacional Of Biodiversidad Inbio |
Lise A.A.,Grande Rio University
Zootaxa | Year: 2012
Two new species of the spider genus Enna O. Pickard-Cambridge, 1897 from Costa Rica and Peru are described and illustrated: Enna osaensis sp. nov. (female, Costa Rica) and E. moyobamba sp. nov. (female, Peru). The male of E. chickeringi Silva, Lise & Carico, 2008, from Costa Rica, is described and illustrated for the first time. Enna huarinilla Silva, Lise & Carico, 2008 is a junior synonym of Enna caliensis Silva, Lise & Carico, 2008. Enna baeza Silva, Lise & Carico, 2008, E. bonaldoi Silva, Lise & Carico, 2008, E. igarape Silva, Lise & Carico, 2008 and E. trivittata Silva & Lise, 2009 are newly recorded from Peru. Paradossenus junin Carico & Silva, 2010 is transferred to Enna O. Pickard-Cambridge, 1897. Trechalea boliviensis Carico, 1993 and Trechalea lomalinda Carico, 1993 are transferred to Syntrechalea F.O.P.-Cambridge, 1902. New records of Syntrechalea lomalinda comb. nov. are reported to Venezuela and Brazil. Copyright © 2012 Magnolia Press.
Wolfe J.D.,U.S. Department of Agriculture |
Wolfe J.D.,Klamath Bird Observatory |
Ralph C.J.,U.S. Department of Agriculture |
Ralph C.J.,Klamath Bird Observatory |
Elizondo P.,Instituto Nacional Of Biodiversidad Inbio
Oecologia | Year: 2015
The effects of habitat alteration and climatic instability have resulted in the loss of bird populations throughout the globe. Tropical birds in particular may be sensitive to climate and habitat change because of their niche specialization, often sedentary nature, and unique life-cycle phenologies. Despite the potential influence of habitat and climatic interactions on tropical birds, we lack comparisons of avian demographics from variably aged forests subject to different climatic phenomena. Here, we measured relationships between forest type and climatic perturbations on White-collared Manakin (Manacus candei), a frugivorous tropical bird, by using 12 years of capture data in young and mature forests in northeastern Costa Rica. We used Cormack–Jolly–Seber models and an analysis of deviance to contrast the influence of the El Niño Southern Oscillation (ENSO) on manakin survival. We found that ENSO had little effect on manakin survival in mature forests. Conversely, in young forests, ENSO explained 79 % of the variation where dry El Niño events negatively influenced manikin survival. We believe mature forest mitigated negative effects of dry El Niño periods and can serve as refugia for some species by buffering birds from climatic instability. Our results represent the first published documentation that ENSO influences the survival of a resident Neotropic landbird. © 2015, Springer-Verlag Berlin Heidelberg (outside the USA).
Devries P.J.,University of New Orleans |
Alexander L.G.,University of New Orleans |
Chacon I.A.,Instituto Nacional Of Biodiversidad Inbio |
Fordyce J.A.,University of Tennessee at Knoxville
Journal of Animal Ecology | Year: 2012
Documenting species abundance distributions in natural environments is critical to ecology and conservation biology. Tropical forest insect faunas vary in space and time, and these partitions can differ in their contribution to overall species diversity. In the Neotropics, the Central American butterfly fauna is best known in terms of general natural history, but butterfly community diversity is best documented by studies on South American fruit-feeding butterflies. Here, we present the first long-term study of fruit-feeding nymphalid species diversity from Central America and provide a unique comparison between Central and South American butterfly communities. This study used 60months of sampling among multiple spatial and temporal partitions to assess species diversity in a Costa Rican rainforest butterfly community. Abundance distributions varied significantly at the species and higher taxonomic group levels, and canopy and understorey samples were found to be composed of distinct species assemblages. Strong similarities in patterns of species diversity were found between this study and one from Ecuador; yet, there was an important difference in how species richness was distributed in vertical space. In contrast to the Ecuadorian site, Costa Rica had significantly higher canopy richness and lower understorey richness. This study affirms that long-term sampling is vital to understanding tropical insect species abundance distributions and points to potential differences in vertical structure among Central and South American forest insect communities that need to be explored. © 2011 The Author. Journal of Animal Ecology © 2011 British Ecological Society.
Yanoviak S.P.,University of Arkansas at Little Rock |
Silveri C.,University of Arkansas |
Hamm C.A.,Michigan State University |
Solis M.,Instituto Nacional Of Biodiversidad Inbio
Journal of Tropical Ecology | Year: 2012
Climbing plants provide efficient pathways for ants to access patchy arboreal resources. However, plant stems vary greatly in physical characteristics that are likely to influence ant locomotion. We collected, measured and identified ants foraging on 671 stems of climbing plants at the La Selva Biological Station, Costa Rica. We applied tuna baits to 70% of the observed stems to attract ants to a broad range of stem sizes. We used these data to examine relationships between relative stem roughness, growth form (herbaceous or woody), stem diameter and the body length of foraging ants representing 58 species. The size of the largest ants found on stems generally increased with stem size up to 3.2 mm diameter, whereas the size of the smallest ants present on stems did not vary with stem diameter. The largest ants in the forest (Paraponera clavata) used small stems (<2.7 mm diameter) only when attracted by baits. Average (± SE) ant body length was larger on woody (5.2 ± 0.32 mm) vs. herbaceous (3.3 ± 0.53 mm) stems, but did not differ between rough and smooth stems within these categories. Ant body-size distribution tended toward unimodality on smooth stems. We conclude that small stem diameter acts as a habitat filter based on ant body size, but only for the largest ants in the forest. The filter effect is reduced when ants are attracted to an artificially high quality resource. © Cambridge University Press 2012.
Ferrer-Paris J.R.,Venezuelan Institute for Scientific Research |
Rodriguez J.P.,Venezuelan Institute for Scientific Research |
Good T.C.,Venezuelan Institute for Scientific Research |
Sanchez-Mercado A.Y.,Venezuelan Institute for Scientific Research |
And 3 more authors.
Diversity and Distributions | Year: 2013
Aim: To test a method for rapidly and reliably collecting species distribution and abundance data over large tropical areas [known as Neotropical Biodiversity Mapping Initiative (NeoMaps)], explicitly seeking to improve cost- and time-efficiencies over existing methods (i.e. museum collections, literature), while strengthening local capacity for data collection. Location: Venezuela. Methods: We placed a grid over Venezuela (0.5 × 0.5 degree cells) and applied a stratified sampling design to select a minimum set of 25 cells spanning environmental and biogeographical variation. We implemented standardized field sampling protocols for birds, butterflies and dung beetles, along transects on environmental gradients ('gradsects'). We compared species richness estimates from our field surveys at national, bioregional and cell scales to those calculated from data compiled from museum collections and the literature. We estimated the variance in richness, composition, relative abundance and diversity between gradsects that could be explained by environmental and biogeographical variables. We also estimated total survey effort and cost. Results: In one field season, we covered 8% of the country and recorded 66% of all known Venezuelan dung beetles, 52% of Pierid butterflies and 37% of birds. Environmental variables explained 27-60% of variation in richness for all groups and 13-43% of variation in abundance and diversity in dung beetles and birds. Bioregional and environmental variables explained 43-58% of the variation in the dissimilarity matrix between transects for all groups. Main conclusions: NeoMaps provides reliable estimates of richness, composition and relative abundance, required for rigorous monitoring and spatial prediction. NeoMaps requires a substantial investment, but is highly efficient, achieving survey goals for each group with 1-month fieldwork and about US$ 1-8 per km2. Future work should focus on other advantages of this type of survey, including the ability to monitor the changes in relative abundance and turnover in species composition, and thus overall diversity patterns. © 2012 Blackwell Publishing Ltd.
Cao S.,Harvard University |
McMillin D.W.,Dana-Farber Cancer Institute |
Tamayo G.,Instituto Nacional Of Biodiversidad Inbio |
Delmore J.,Dana-Farber Cancer Institute |
And 2 more authors.
Journal of Natural Products | Year: 2012
CR1642D, an endophytic isolate of Penicillium sp. collected from a Costa Rican rainforest, was identified through a high-throughput approach to identify natural products with enhanced antitumor activity in the context of tumor-stromal interactions. Bioassay-guided separation led to the identification of five xanthones (1-5) from CR1642D. The structures of the xanthone dimer penexanthone A (1) and monomer penexanthone B (2) were elucidated on the basis of spectroscopic analyses, including 2D NMR experiments. All of the compounds were tested against a panel of tumor cell lines in the presence and absence of bone marrow stromal cells. Compound 3 was the most active, with IC50 values of 1-17 μM, and its activity was enhanced 2-fold against tumor cell line RPMI8226 in the presence of stromal cells (IC50 1.2 μM, but 2.4 μM without stromal cells). © 2012 The American Chemical Society and American Society of Pharmacognosy.
Tripathi A.,University of Michigan |
Schofield M.M.,University of Michigan |
Chlipala G.E.,University of Michigan |
Schultz P.J.,University of Michigan |
And 8 more authors.
Journal of the American Chemical Society | Year: 2014
Siderophores are high-affinity iron chelators produced by microorganisms and frequently contribute to the virulence of human pathogens. Targeted inhibition of the biosynthesis of siderophores staphyloferrin B of Staphylococcus aureus and petrobactin of Bacillus anthracis hold considerable potential as a single or combined treatment for methicillin-resistant S. aureus (MRSA) and anthrax infection, respectively. The biosynthetic pathways for both siderophores involve a nonribosomal peptide synthetase independent siderophore (NIS) synthetase, including SbnE in staphyloferrin B and AsbA in petrobactin. In this study, we developed a biochemical assay specific for NIS synthetases to screen for inhibitors of SbnE and AsbA against a library of marine microbial-derived natural product extracts (NPEs). Analysis of the NPE derived from Streptomyces tempisquensis led to the isolation of the novel antibiotics baulamycins A (BmcA, 6) and B (BmcB, 7). BmcA and BmcB displayed in vitro activity with IC50 values of 4.8 μM and 19 μM against SbnE and 180 μM and 200 μM against AsbA, respectively. Kinetic analysis showed that the compounds function as reversible competitive enzyme inhibitors. Liquid culture studies with S. aureus, B. anthracis, E. coli, and several other bacterial pathogens demonstrated the capacity of these natural products to penetrate bacterial barriers and inhibit growth of both Gram-positive and Gram-negative species. These studies provide proof-of-concept that natural product inhibitors targeting siderophore virulence factors can provide access to novel broad-spectrum antibiotics, which may serve as important leads for the development of potent anti-infective agents © 2014 American Chemical Society.
The case of Lonchocarpus costaricensis (Leguminosae, Papilionoideae), an endemic species of Costa Rica: A taxonomic-nomenclatural complex, and a new species [El caso de Lonchocarpus costaricensis (Leguminosae, Papilionoideae), una especie endémica de Costa Rica: Un complejo taxonómico-nomenclatural, y una nueva especie]
Zamora N.A.,Instituto Nacional Of Biodiversidad Inbio
Anales del Jardin Botanico de Madrid | Year: 2011
Mixed collections, a lack of type specimen designation and strong morphological similarity between collections cited in the Derris costaricensis protologue has led to a very confused taxonomic and nomenclatural situation surrounding the species Lonchocarpus costaricensis (Donn. Sm.) Pittier; a detailed taxonomic study has revealed that a new species (Lonchocarpus felipei N. Zamora) here described, is involved. Also, the original lectotipification of Lonchocarpus macrocarpus Benth., is re-establish it here.
Kriebel R.,University of Wisconsin - Madison |
Zumbado M.A.,Instituto Nacional Of Biodiversidad Inbio
Brittonia | Year: 2014
We report observations of generalist insect visitation and probable pollination of the flowers of Miconia brevitheca and M. tonduzii var. tonduzii, both of which belong to Miconia section Cremanium. The most diverse assemblage of insect visitors was recorded for M. brevitheca, which has some of the smallest flowers in the Melastomataceae. Visitors included butterflies of at least five families. Miconia tonduzii, on the other hand, was visited mostly by Diptera of the families Syrphidae and Tachinidae. Scanning electron microscopy revealed stomata on the lower part of the anthers on the abaxial surface, which has been recently reported in other melastomes as the nectar-secreting site. Flowers of a closely related buzz pollinated control, Leandra subseriata, confirmed the absence of stomata in the flowers of this species. Flowers of these Miconia also are unusual in that they have broad pores, filaments that are geniculate at the middle of their length, and short styles that are not exserted beyond the stamens (not herkogamous). The floral morphology, along with observations of many generalist insect visitors and almost no buzzing bees, suggest these species are generalist pollinated. The implications of these observations are relevant to the understanding of pollinator systems, because the lineage to which these species belong, Miconia section Cremanium, is nested in a bee-pollinated clade, adding support to previous suggestions of a shift from pollinator specialization to generalization. © 2014, by the New York Botanical Garden.
Cao S.,Harvard University |
Ross L.,Harvard University |
Tamayo G.,Instituto Nacional Of Biodiversidad Inbio |
Clardy J.,Harvard University
Organic Letters | Year: 2010
An endophytic fungus isolated from the small palm Asterogyne martiana produced two unusual steroid-like metabolites, asterogynin A (1) and asterogynin B (2), along with the known compounds viridiol (3) and viridin (4). Asterogynins A and B were characterized by NMR and MS spectroscopic analysis. © 2010 American Chemical Society.