Oleas Gallo, Nora Helena
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Oleas Gallo, Nora Helena
Main Affiliation
Quito
Email
noraoleas@uti.edu.ec
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Scopus Author ID
12645534600

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Molecular Systematics of Threatened Seed Plant Species Endemic in the Caribbean Islands

2013 , Oleas Gallo, Nora Helena , Jestrow B. , Calonje M. , Peguero B. , Jiménez F. , Rodríguez-Peña R. , Oviedo R. , Santiago-Valentín E. , Meerow A.W. , Abdo M. , Maunder M. , Griffith M.P. , Francisco-Ortega J.

A review of available Caribbean Island red-lists species (CR and EN categories based on the IUCN guidelines from 2001, and E category established according to the IUCN guidelines from 1980) is presented. A database of over 1,300 endemic species that are either Critically Endangered or Endangered sensu IUCN was created. There are molecular systematic studies available for 112 of them. Six of these species (in six genera) are the only members of early divergent lineages that are sister to groups composed of a large number of clades. Seven of the species (in seven genera) belong to clades that have a small number of taxa but are sister to species/genus-rich clades. Ten of the species (in six genera) are sister to taxa restricted to South America or nested in clades endemic to this region. Fifty-seven of the species (in 35 genera) are sister to Caribbean Island endemic species. Erigeron belliastroides, an Endangered (EN) Cuban endemic, is sister to the Galapagos genus Darwiniothamnus. The phylogenetic placement of four of the threatened species resulted in changes in their taxonomic placement; they belong to polyphyletic or paraphyletic genera. © 2013 The New York Botanical Garden.

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Alkaloids of Phaedranassa dubia (Kunth) J.F. Macbr. and Phaedranassa brevifolia Meerow (Amaryllidaceae) from Ecuador and its cholinesterase-inhibitory activity

2021 , León K.A. , Inca A. , Tallini L.R. , Osorio E.H. , Robles J. , Bastida J. , Oleas Gallo, Nora Helena

Alzheimer's disease is considered the most common cause of dementia and, in an increasingly aging population worldwide, the quest for treatment is a priority. Amaryllidaceae alkaloids are of main interest because of their cholinesterase inhibition potential, which is the main palliative treatment available for this disease. We evaluated the alkaloidal profile and the in vitro inhibitory activity on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) of bulb alkaloid extract of Phaedranassa dubia and Phaedranassa brevifolia collected in Ecuador. Using gas chromatography coupled to mass spectrometry (GC-MS), we identified typical Amaryllidaceae alkaloids in these species, highlighting the presence of lycorine-type alkaloids in P. dubia and haemanthamine/crinine-type in P. brevifolia. The species P. dubia and P. brevifolia showed inhibitory activities against AChE (IC50 values of 25.48 ± 0.39 and 3.45 ± 0.29 μg.mL−1, respectively) and BuChE (IC50 values of 114.96 ± 4.94 and 58.89 ± 0.55 μg.mL−1, respectively). Computational experiments allowed us to understand the interactions of the alkaloids identified in these samples toward the active sites of AChE and BuChE. In silico, some alkaloids detected in these Amaryllidaceae species presented higher estimated binding free energy toward BuChE than galanthamine. This is the first study about the alkaloid profile and biological potential of P. brevifolia species. © 2020 SAAB

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Phylogeny of Weinmannia (Cunoniaceae) reveals the contribution of the southern extratropics to tropical Andean biodiversity

2025 , Ricardo A. Segovia , Eduardo Aguirre-Mazzi , Christine E. Edwards , Alexander G. Linan , Alfredo Fuentes , Andrea Chaspuengal , Kyle G. Dexter , Francisco Fajardo-Gutiérrez , William Farfan-Rios , Oleas Gallo, Nora Helena , Juan C. Penagos Zuluaga , J. Sebastián Tello

The Andes are a relatively young mountain range with impressive biodiversity, but the biogeographic processes underlying its hyperdiversity are still being unraveled. Novel mid- to high-elevation climates may have served as a biological corridor for the immigration of temperate-adapted lineages to more equatorial latitudes, contributing unknown levels of diversity to this region. We tested the hypothesis that Weinmannia is a lineage of extratropical origin that recently reached and then diversified extensively in the tropical Andes. Using a 2bRAD seq approach to generate a time-calibrated phylogeny for the genus, we found that extratropical species were placed as sister to the rest of Weinmannia and that younger clades were distributed towards more equatorial latitudes. Although Weinmannia exhibited low niche conservatism in elevation and latitude, trait reconstructions of climatic variables showed that the common ancestor of Weinmannia occupied cool climates, with high conservatism of thermal and water availability niche across the phylogeny. Thus, Andean uplift likely created habitats with suitable environmental conditions, providing a dispersal route for extant Weinmannia to colonize the tropical Andes from the southern extratropics. These southern lineages likely converged with those originating in other tropical and extratropical centers of diversification, providing multiple origins for the hyperdiversity in the modern montane forests of the tropical Andes.

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Muddy boots beget wisdom: Implications for rare or endangered plant species distribution models

2019 , Oleas Gallo, Nora Helena , Feeley K.J. , Fajardo J. , Meerow A.W. , Gebelein J. , Francisco-Ortega J.

Species distribution models (SDMs) are popular tools for predicting the geographic ranges of species. It is common practice to use georeferenced records obtained from online databases to generate these models. Using three species of Phaedranassa (Amaryllidaceae) from the Northern Andes, we compare the geographic ranges as predicted by SDMs based on online records (after standard data cleaning) with SDMs of these records confirmed through extensive field searches. We also review the identification of herbarium collections. The species' ranges generated with corroborated field records did not agree with the species' ranges based on the online data. Specifically, geographic ranges based on online data were significantly inflated and had significantly different and wider elevational extents compared to the ranges based on verified field records. Our results suggest that to generate accurate predictions of species' ranges, occurrence records need to be carefully evaluated with (1) appropriate filters (e.g., altitude range, ecosystem); (2) taxonomic monographs and/or specialist corroboration; and (3) validation through field searches. This study points out the implications of generating SDMs produced with unverified online records to guide species-specific conservation strategies since inaccurate range predictions can have important consequences when estimating species' extinction risks. © 2019 by the authors.

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Genotyping‐by‐sequencing informs conservation of Andean palms sources of non‐timber forest products

2024 , Nicolás Peñafiel Loaiza , Abigail H. Chafe , Mónica Moraes R , Oleas Gallo, Nora Helena , Julissa Roncal

Conservation and sustainable management of lineages providing non‐timber forest products are imperative under the current global biodiversity loss. Most non‐timber forest species, however, lack genomic studies that characterize their intraspecific variation and evolutionary history, which inform species' conservation practices. Contrary to many lineages in the Andean biodiversity hotspot that exhibit high diversification, the genus Parajubaea (Arecaceae) has only three species despite the genus' origin 22 million years ago. Two of the three palm species, P. torallyi and P. sunkha, are non‐timber forest species endemic to the Andes of Bolivia and are listed as IUCN endangered. The third species, P. cocoides, is a vulnerable species with unknown wild populations. We investigated the evolutionary relationships of Parajubaea species and the genetic diversity and structure of wild Bolivian populations. Sequencing of five low‐copy nuclear genes (3753 bp) challenged the hypothesis that P. cocoides is a cultigen that originated from the wild Bolivian species. We further obtained up to 15,134 de novo single‐nucleotide polymorphism markers by genotyping‐by‐sequencing of 194 wild Parajubaea individuals. Our total DNA sequencing effort rejected the taxonomic separation of the two Bolivian species. As expected for narrow endemic species, we observed low genetic diversity, but no inbreeding signal. We found three genetic clusters shaped by geographic distance, which we use to propose three management units. Different percentages of missing genotypic data did not impact the genetic structure of populations. We use the management units to recommend in situ conservation by creating new protected areas, and ex situ conservation through seed collection.

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Community voices: the importance of diverse networks in academic mentoring

2022 , Deanna, R. , Merkle, B.G. , Chun, K.P. , Navarro-Rosenblatt, D. , Baxter, I. , Oleas Gallo, Nora Helena , Bortolus, A. , Geesink, P. , Diele-Viegas, L. , Aschero, V. , de Leone, M.J. , Oliferuk, S. , Zuo, R. , Cosacov, A. , Grossi, M. , Knapp, S. , Lopez-Mendez, A. , Welchen, E. , Ribone, P. , Auge, G.

[No abstract available]

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Water quality assessment of the cutuchi river basin (Ecuador): A review of technical documents

2021 , Zapata D. , Oleas Gallo, Nora Helena , Páez-Vacas, Mónica , Tobes, Ibon

The Cutuchi River Basin extends over the inter-Andean valley south of the Cotopaxi Volcano, in Ecuador. It flows through two provinces, Cotopaxi and Tungurahua, and its waters are extensively used to irrigate crops that provide food to the main cities in the country. Unfortunately, the basin receives untreated domestic and industrial discharges. The need for an environmental quality assessment of the river has been acknowledged over the years. The aim of this study is to gather information about water quality of the Cutuchi River through a historical bibliographic review. A total of 57 works published between 2007 and 2018 were found, including books, articles, thesis and project reports. Only 18 documents provided biological, physical, or chemical data linked to water quality. The data obtained through the literature review were compared with maximum thresholds from national and international regulations. Unfortunately, revised studies were scattered on time and randomly along the basin and did not provide robust information to evaluate the state of the water-system. Some contamination was detected significantly exceeding safety thresholds. More exhaustive studies along the basin are needed as a baseline to help the decision makers to design management plans and mitigate human impacts. © 2020 Institute of Physics Publishing. All rights reserved.

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Trees of Amazonian Ecuador: a taxonomically verified species list with data on abundance and distribution

2019 , Guevara Andino J.E. , Pitman N.C.A. , Ulloa Ulloa C. , Romoleroux K. , Fernández-Fernández D. , Ceron C. , Palacios W. , Neill D.A. , Oleas Gallo, Nora Helena , Rivas Torres G. , Altamirano P. , ter Steege H.

We compiled a data set for all tree species collected to date in lowland Amazonian Ecuador in order to determine the number of tree species in the region. This data set has been extensively verified by taxonomists and is the most comprehensive attempt to evaluate the tree diversity in one of the richest species regions of the Amazon. We used four main sources of data: mounted specimens deposited in Ecuadorian herbaria only, specimen records of a large-scale 1-hectare-plot network (60 plots in total), data from the Missouri Botanical Garden Tropicos® database (MO), and literature sources. The list of 2,296 tree species names we provide in this data set is based on 47,486 herbarium records deposited in the following herbaria: Alfredo Paredes Herbarium (QAP), Catholic University Herbarium (QCA), Herbario Nacional del Ecuador (QCNE), Missouri Botanical Garden (MO), and records from an extensive sampling of 29,768 individuals with diameter at breast height (dbh) ≥10 cm recorded in our plot network. We also provide data for the relative abundance of species, geographic coordinates of specimens deposited in major herbaria around the world, whether the species is native or endemic, current hypothesis of geographic distribution, representative collections, and IUCN threat category for every species recorded to date in Amazonian Ecuador. These data are described in Metadata S1 and can be used for macroecological, evolutionary, or taxonomic studies. There are no copyright restrictions; data are freely available for noncommercial scientific use (CC BY 3.0). Please see Metadata S1 (Class III, Section B.1: Proprietary restrictions) for additional information on usage. © 2019 The Authors. Ecology © 2019 The Ecological Society of America

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Conservation profile of endemic species of Berberis from Ecuador (Berberidaceae, Ranunculales)

2025 , Carmen Ulloa Ulloa , Sánchez Lara, Enmily , Oleas Gallo, Nora Helena

Background The plant family Berberidaceae is represented in Ecuador by a single genus, Berberis. It comprises 15 species, seven endemic to the high Andean forests and páramos above 2,400 meters of altitude. These ecosystems, globally recognized for their exceptional biodiversity, are increasingly threatened by fragmentation and degradation, placing endemic species at serious risk of extinction. The conservation status of Berberis species in Ecuador was last assessed more than 20 years ago, underscoring the urgent need for a comprehensive and updated evaluation. New information This study presents IUCN Red List assessments for all endemic species of the genus Berberis in Ecuador. Incorporating the latest taxonomic revision, we evaluate Berberis engleriana and B. rigida for the first time. Among the five species previously assessed, three have retained their original conservation status, while two are now classified under a higher threat category. Conservation measures are proposed to mitigate extinction risk and support the preservation of these species.

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Population genetic structure of Phaedranassa cinerea Ravenna (Amaryllidaceae) and conservation implications

2025 , María Belén Buenaño , Carmen Ulloa Ulloa , Javier Francisco-Ortega , Alan W. Meerow , Oleas Gallo, Nora Helena

Background: Andean orography has shaped the endemism of plant species in montane forests, creating a mosaic of habitats in small and isolated areas. Understanding these endemic species' genetic diversity patterns is crucial for their conservation. Phaedranassa cinerea (Amaryllidaceae), a species restricted to the western Andes of Ecuador, is listed as “vulnerable” according to the IUCN criteria. This study seeks to determine whether there is genetic structure among and within Phaedranassa cinerea populations, estimate the timing of their genetic divergence, and recommend conservation strategies based on these genetic structure findings. Results: Using 13 microsatellites and a Bayesian approach, we analyzed the genetic differentiation of P. cinerea and possible diversification scenarios. Our results indicate that the genetic diversity of P. cinerea is lower than congeneric species. The Bayesian analysis identified two genetic groups, with no evidence of isolation by distance. Populations in the northwest of the Ecuadorean Andes have less allele richness compared to those in the southwest. Additionally, the species exhibits excess homozygosity and evidence of bottlenecks. Our Bayesian analysis suggests that the differentiation among populations was not older than 5,000 years and was as recent as 600 years ago for some of the populations. Based on the geographic distribution of the known populations, the species should be listed as endangered instead of vulnerable to extinction. Conclusions: Phaedranassa cinerea shows lower genetic diversity than related species, with the most variation within populations. We identified two to four genetic groups, suggesting recent divergence along the ridges of the western Andes. The findings suggest that conservation efforts should focus on securing genetic exchange between populations to preserve the genetic diversity of P. cinerea.

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