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

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Molecular Markers and Conservation of Plant Species in the Latin-America: The Case of Phaedranassa viridiflora (Amaryllidaceae)

2013 , Oleas Gallo, Nora Helena , Meerow A.W. , Francisco-Ortega J.

Phaedranassa viridiflora (Amaryllidaceae) is an endemic and endangered plant restricted to the Northern Andes in Ecuador. It is known in three locations where it is sympatric with other Phaedranassa species. Phaedranassa viridiflora is the only species of the genus with yellow flowers. We analyzed 13 microsatellite loci to elucidate the genetic structure of the populations of P. viridiflora. Our results provided the first evidence of natural hybridization in the genus (between P. viridiflora and P. dubia in the Pululahua crater of northern Ecuador). The central and southern populations did not show hybridization. Genetic diversity was the highest in the Pululahua population. Central and southern populations have a higher proportion of clones than Pululahua. Bayesian and cluster analysis suggest that the yellow flower type evolved at least three times along the Ecuadorean Andes. In contrast to other Phaedranassa species, Phaedranassa viridiflora shows lower genetic diversity, which is likely related to a vegetative reproductive strategy. © 2013 The New York Botanical Garden (outside the USA).

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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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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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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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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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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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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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Expelled by the Antarctic ice: Evolutionary history of the tribe Cunonieae (Cunoniaceae)

2025 , Francisco Fajardo‐Gutiérrez , Mariasole Calbi , Markus S. Dillenberger , Sebastian Tello , Alfredo Fuentes , Oleas Gallo, Nora Helena , Ricardo A. Segovia , Christine E. Edwards , Yohan Pillon , James E. Richardson , Thomas Borsch

The tribe Cunonieae comprises five genera and 214 species of shrubs and trees currently distributed in the Southern Hemisphere and the tropics, exhibiting an amphi-Pacific disjunct distribution shared with Araucariaceae, Myrtaceae, Nothofagaceae, Podocarpaceae, and Proteaceae, among others. To address the central question of how historical geological forces have shaped the distribution of plant diversity in the southern hemisphere, we aimed to provide evidence from the biogeographical history of Cunonieae. We generated the most densely sampled phylogenetic trees of Cunonieae available to date, with 121 samples and 81 species, based on 404 new sequences of plastid and nuclear DNA regions with high hierarchical phylogenetic signal (matK, trnL-F, rpl16, and internal transcribed spacer (ITS)). We included 184 samples of Rosids to estimate divergence times using fossil calibration points. For biogeographic inference, we employed a time-stratified model including fossils as tips. Cunonia and Pterophylla were paraphyletic in the ITS tree, and Cunonia was paraphyletic in the plastid tree. Pancheria, Vesselowskya, and Weinmannia were monophyletic, the latter with conflicting nuclear and plastid phylogenies. The crown group Cunonieae was dated at ~56 Ma, and its ancestral areas were Antarctica and Patagonia. Antarctica acted as a bridge between Australia and South America before the consolidation of the Antarctic Ice Sheet and the extinction of the lineage in Antarctica from the Oligocene to the Miocene. Following that, Cunonieae spread to lower latitudes via Zealandia/Oceania and Patagonia/South America. Geological changes during the Pliocene facilitated a further burst in diversification along the Andes, in Madagascar, and in New Caledonia, where at least three colonization events occurred

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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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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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