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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Typification of names of Weinmannia (Cunoniaceae) of species described by José Cuatrecasas from Colombian collections

2025 , Carmen Ulloa Ulloa , Andrea Chaspuengal-Morales , Francisco Fajardo-Gutiérrez , Oleas Gallo, Nora Helena

We propose 18 new lectotype designations for names of Weinmannia, five of which are second-step typifications involving four inadvertent first-step lectotype designations, and 13 of them are designations of one single duplicate at the herbarium where deposited. José Cuatrecasas described all, but one, of the taxa from collections made in Colombia. We clarify the lectotypification for Weinmannia parvifoliolata Cuatrec. Finally, we propose one lectotype designation for W. cochensis described by Georg Hieronymus.

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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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First records of the genus Pyrolirion Herb. (Liliopsida, Asparagales, Amaryllidaceae) in Ecuador

2025 , Oleas Gallo, Nora Helena , Lou Jost , Ricardo Zambrano C. , Cristian Guzmán Torres , Jorge Heredia , Martin Bustamante , Hugo Romero-Saltos , María Paulina Moreno-Armijos , Alan W. Meerow , Catalina Quintana

We report for the first time in Ecuador the small plant genus Pyrolirion Herb. (Amaryllidaceae). We identify several Ecuadorian populations of Pyrolirion tubiflorum (L’Hér.) M. Roem. located in four provinces along the Ecuadorian Andes. This species has been previously recorded in Peru, Bolivia, and Chile. An updated description of P. tubiflorum is provided, along with detailed photographs of some of the Ecuadorian examples of the species.

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Isolation and Characterisation of 11 Microsatellite Loci in the Ecuadorian Hillstar Oreotrochilus chimborazo

2017 , Oleas Gallo, Nora Helena , Harvey N. , Rodríguez-Saltos C.A. , Bonaccorso E.

The Ecuadorian Hillstar Oreotrochilus chimborazo is a high Andean hummingbird that inhabits paramo ecosystems from extreme southern Colombia to southern Ecuador. The species is currently divided into three subspecies that differ in morphology and geographic distribution but no molecular differences have been found between them using mitochondrial markers. The aim of this study was to isolate and test microsatellite loci to further explore possible genetic variability between and within these subspecies. Screening an enriched genomic library of O. chimborazo we obtained eleven polymorphic microsatellite loci. These markers will be used to further elucidate evolutionary patterns in the species.

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Alkaloid Profiling and Anti-Cholinesterase Potential of Three Different Genera of Amaryllidaceae Collected in Ecuador: Urceolina Rchb., Clinanthus Herb. and Stenomesson Herb.

2024 , Luciana R. Tallini , Karen Acosta León , Raúl Chamorro , Edison H. Osorio , Jaume Bastida , Lou Jost , Oleas Gallo, Nora Helena

Ecuador is an important center of biodiversity for the plant subfamily Amaryllidoideae, known for its important bioactive molecules. This study aimed to assess the chemical and biological potential of four different Amaryllidoideae species collected in Ecuador: Urceolina formosa, Urceolina ruthiana, Clinanthus incarnatus, and Stenomesson aurantiacum. Twenty-six alkaloids were identified in the bulb extracts of these species using GC-MS. The extract of S. aurantiacum exhibited the greatest structural diversity and contained the highest amounts of alkaloids, particularly lycorine and galanthamine. Only for this species, identification of all the alkaloids belonging to this chemical profile was not possible. Six of them remain unidentified. The potential of these three Amaryllidoideae genera against Alzheimer’s disease was then evaluated by measuring their AChE and BuChE inhibitory activity, revealing that C. incarnatus and U. formosa (from Sucumbíos province) showed the best results with IC50 values of 1.73 ± 0.25 and 30.56 ± 1.56 µg·mL−1, respectively. Molecular dynamic assays were conducted to characterize the possible interactions that occurs among 2-hydroxyanhydrolycorine and the AChE enzyme, concluded that it is stabilized in the pocket in a similar way to galanthamine. This study expands our understanding of the biodiversity of Amaryllidoideae species from Ecuador, highlighting their potential as source of chemical compounds with pharmaceutical applications.

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Taxonomy based on science is necessary for global conservation

2018 , Thomson S.A. , Pyle R.L. , Ahyong S.T. , Alonso-Zarazaga M. , Ammirati J. , Araya J.F. , Ascher J.S. , Audisio T.L. , Oleas Gallo, Nora Helena

[No abstract available]

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In vitro and in silico analysis of galanthine from Zephyranthes carinata as an inhibitor of acetylcholinesterase

2022 , Sierra, K. , de Andrade, J.P. , R. Tallini, L. , Osorio, E.H. , Yañéz, O. , Osorio, M.I. , Oleas Gallo, Nora Helena , García-Beltrán, O. , de S. Borges, W. , Bastida, J. , Osorio, E. , Cortes, N.

Zephyranthes carinata Herb., a specie of the Amaryllidoideae subfamily, has been reported to have inhibitory activity against acetylcholinesterase. However, scientific evidence related to their bioactive alkaloids has been lacking. Thus, this study describes the isolation of the alkaloids of this plant, and their inhibition of the enzymes acetylcholinesterase (eeAChE) and butyrylcholinesterase (eqBuChE), being galanthine the main component. Additionally, haemanthamine, hamayne, lycoramine, lycorine, tazettine, trisphaeridine and vittatine/crinine were also isolated. The results showed that galanthine has significant activity at low micromolar concentrations for eeAChE (IC50 = 1.96 μg/mL). The in-silico study allowed to establish at a molecular level the high affinity and the way galanthine interacts with the active site of the TcAChE enzyme, information that corroborates the result of the experimental IC50. However, according to molecular dynamics (MD) analysis, it is also suggested that galanthine presents a different inhibition mode that the one observed for galanthamine, by presenting interaction with peripheral anionic binding site of the enzyme, which prevents the entrance and exit of molecules from the active site. Thus, in vitro screening assays plus rapid computer development play an essential role in the search for new cholinesterase inhibitors by identifying unknown bio-interactions between bioactive compounds and biological targets. © 2022 The Authors

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Evolutionary history of CAM photosynthesis in Neotropical Clusia: Insights from genomics, anatomy, physiology and climate

2022 , Luján, M. , Oleas Gallo, Nora Helena , Winter, K.

Clusia is a remarkable genus of Neotropical woody plants as its members engage in either C3 photosynthesis or employ, to varying degrees, crassulacean acid metabolism (CAM) photosynthesis. Information about the evolutionary history of CAM in Clusia is scarce. Restriction site-associated sequencing of 64 species (20% of the genus) provided strong support for most of the previously recognized nine lineages. Ancestral reconstruction using maximum parsimony or maximum likelihood under a one-rate model suggested that CAM evolved at least four times independently from a most recent common ancestor (MRCA) with C3, whereas a maximum likelihood two-rate model suggested that CAM was already present in the MRCA followed by reversions to C3 in several lineages. Phylogenetic generalized least square analysis assessed variation in seven leaf anatomical traits and CAM activity measured as δ13C. Results indicate that CAM is highly correlated with palisade mesophyll layer thickness and cell size. In addition, correlation between 19 bioclimatic variables and δ13C was evaluated. It was found that CAM is positively correlated with habitats with a more severe dry season and greater precipitation seasonality. Since CAM is weakly and/or only periodically expressed in many Clusia spp., and thus not readily reflected in δ13C, future analysis of phylogenetically-informed CAM expression in Clusia must include physiological measurements such as CO2 exchange and/or diel changes in leaf acidity for each species under investigation. © 2021 The Linnean Society of London,.

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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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