The San Luis Polylepis Forest at 3,940 meters (12,926 ft) above sea level, the Toreadora Lagoon, el Cajas National Park, Cuenca, the Highlands Southern, Ecuador.
Image by ER’s Eyes – Our planet is so beautiful.
The genus Polylepis contains about twenty species that are distributed across the Andes. It is in the rose family, Rosaceae. The genus belongs to the tribe Sanguisorbeae, which mainly comprises herbs and small shrubs. Although the relationship of Polylepis to other genera of Sanguisorbeae is largely unknown, the analysis of Torsten Eriksson et al. (2003) showed evidence of a close relationship between Polylepis and Acaena, which shows tendencies towards having fused stipular sheaths, reddish, flaking-off bark, and axillary, somewhat pendant inflorescences, features otherwise characteristic of Polylepis. There are several characteristics that are important taxonomically to distinguish between species of Polylepis, for example: 1) The amount of leaf congestion, 2) presence or absence of spurs and their size and vestiture, 3) presence or absence and type of trichomes, (4) size, shape, thickness and vestiture of leaflets. The most important taxonomic character, however, is the leaflets.
Studies suggest that repeated fragmentation and reconnection of páramo vegetation, caused by the Pleistocene climatic fluctuations, had a strong influence on the evolution and speed of speciation in the genus Polylepis as well as the páramo biota as a whole.
