Abstract Detail

Floristics & Taxonomy

Romoleroux , Katya Susana [1], Boza Espinoza, Tatiana Erika [2], Kessler, Michael [3].

New species of Polylepis (Rosaceae) from Ecuador.

Polylepis (Rosaceae) is an emblematic tree genus of the high Andes, representing the natural forest vegetation of the tropical Andes above about 3500 m elevation and forming the highest treelines in the southern hemisphere at over 4800 m. Polylepis forests have been strongly affected by human land use, leading to massive forest fragmentation and the modification of plant assemblages. Taxonomically, the genus Polylepis has long been challenging due to high morphological plasticity, extensive hybridization, and polyploidization. In the first modern revision of the genus, Simpson (1979) recognized 15 broadly delimited species. Later work gradually split up these species to arrive at more morphologically and biogeographically well-defined units. In Ecuador, a total of seven species were traditionally recorded for Polylepis, nevertheless some species have been difficult to recognize, especially P. sericea and P. pauta. These taxonomic problems among Polylepis in Ecuador prompted us to undertake a joint revision of the herbarium collections, coupled with field work at several sites in the Ecuadorian Andean region. As a result of these studies, we here propose a revised classification of the Polylepis pauta and sericea complexes in Ecuador, recognizing five species, three of which are described as new. Polylepis humboldtii T.Boza, K.Romol. & M.Kessler sp. nov., P. loxensis T.Boza, K.Romol. & M.Kessler sp. nov., P. longipilosa T.Boza, K.Romol. & M.Kessler sp. nov., P. ochreata (Wedd.) Bitter, and P. pauta Hieron. Therefore, we now recognize a total of 10 species for Ecuador. We consider that this new classification more realistically captures the morphological, ecological, and biogeographical differences between Polylepis populations in Ecuador and represents a better basis for targeted conservation and management action. In particular, the newly described species P. humboldtii and P. loxensis have very small ranges and population sizes, so that they urgently deserve further study.

1 - Pontificia Universidad Católica del Ecuador, School of Biology, Avenue 12 de Octubre 1076 and Roca, Quito, PICH, 17012184, UK
2 - Universidad Nacional de San Antonio Abad del Cusco, Herbario Vargas CUZ, Avenue de La Cultura 773, Cusco, UK
3 - University of Zurich, Department of Systematic and Evolutionary Botany, Zollikerstrasse 107, Zurich, CH-8008 , UK

Keywords:
morphology
New taxa
Polylepis
reevaluation
Taxonomy.

Presentation Type: Oral Paper
Session: FT1, Floristics & Taxonomy I
Location: Virtual/Virtual
Date: Monday, July 27th, 2020
Time: 11:30 AM
Number: FT1FT007
Abstract ID:678
Candidate for Awards:None