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Type: Article
Published: 2021-10-21
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A taxonomic assessment of Chlorospingus flavopectus phaeocephalus and Chlorospingus semifuscus (Passeriformes: Passerellidae), including the description of a new subspecies

Instituto Nacional de la Biodiversidad del Ecuador (INABIO), calle Rumipamba 341 y Av. de Los Shyris, Casilla 17-07-8976, Quito, Ecuador.
Laboratorio de Biología Evolutiva de Vertebrados, Departamento de Ciencias Biológicas, Universidad de los Andes, Bogotá, Colombia.
Instituto Nacional de la Biodiversidad del Ecuador (INABIO), calle Rumipamba 341 y Av. de Los Shyris, Casilla 17-07-8976, Quito, Ecuador. Universidad Nacional de Colombia, Facultad de Ciencias, Bogotá D.C., Colombia; Grupo de Investigación Evolución y Ecología de Fauna Neotropical. Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Laboratorio de Zoología Terrestre y Museo de Zoología, Campus Cumbayá, Quito 170901, Ecuador.
Université Paris Est Créteil, LAB’URBA, F-94010 Créteil, France. Centre d'Ecologie et des Sciences de la Conservation (CESCO UMR 7204), MNHN, CNRS, Sorbonne Université, CP135, 57 rue Cuvier, 75005 Paris, France.
Institut Systématique Evolution Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, 57 rue Cuvier, CP51, 75005 Paris, France.
American Museum of Natural History, Department of Ornithology, Central Park West at 79th Street, New York, New York 10024-5192. Office: 212-769-5788
Universidad San Francisco de Quito, Laboratorio de Biología Evolutiva, Colegio de Ciencias Biológicas y Ambientales, Ecuador.
Aves bird systematics Andes Ecuador Tumbes-Chocó speciation hybridization speciation barriers population barriers Passerellidae


Chlorospingus flavopectus, a widely distributed member of the New World sparrows and finches (Passerellidae), is among the most variable and complex Neotropical bird species. With up to 28 subspecies that inhabit montane forest from Mexico south to Argentina, it presents a recurring leapfrog pattern, with many genetically differentiated lineages, but even more morphologically distinguishable taxa. Chlorospingus flavopectus phaeocephalus is distributed along the eastern Andean slope (from southern Colombia to northern Peru) and in localized patches along the central and southwestern slopes of the Ecuadorian Andes, in the forest remnants of Chimborazo, El Oro, and adjacent Loja provinces. This allopatric distribution was based on plumage similarities, but no genetic or vocal analysis has tested if these populations share a common ancestry. Here, we compared data for populations of C. f. phaeocephalus, C. semifuscus semifuscus from northwest Ecuador, and C. s. livingstoni from west Colombia, and analyzed them in the context of other Chlorospingus. Our phylogenetic analyses revealed that the putative west Ecuadorian populations of C. f. phaeocephalus are nested within C. semifuscus. They also present diagnostic characters when compared to other populations of C. semifuscus and C. f. phaeocephalus. Based on these results, we recognize the population from El Oro and adjacent Loja Provinces as a new subspecies of C. semifuscus, and the population from Chimborazo Province as a morphological variation of C. s. semifuscus.



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