Oleas Gallo, Nora Helena
Thumbnail Image
Preferred name
Oleas Gallo, Nora Helena
Main Affiliation
Quito
Email
noraoleas@uti.edu.ec
ORCID
Scopus Author ID
12645534600

Research Output

Filters

3
3
Reset filters

Settings
Now showing 1 - 3 of 3
No Thumbnail Available
Publication

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.

View
No Thumbnail Available
Publication

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.

View
No Thumbnail Available
Publication

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.

View