Synopsis of Plazia Ruiz &amp; Pav. (Onoserideae, Asteraceae), including a new species from northern Peru

Michael Dillon,Federico Luebert

doi:10.3897/phytokeys.34.6151

Abstract

A synopsis of Plazia Ruiz & Pav. (Onoserideae, Asteraceae) is presented, including the description of a new species, Plazia robinsonii M.O.Dillon & Sagást., from a locality c. 20 kms west of Huamachuco, Department of La Libertad in northern Peru. It most closely resembles Plazia conferta Ruiz & Pav., a narrow endemic from central Peru some 450 km to the south; however, the latter species has larger leaves and smaller capitula. Plazia is a small genus of four species confined to the Andean Cordillera of Peru, Bolivia, Chile, and Argentina. A distribution map of the four species, an illustration of the new species, a photograph of the holotype, and a key to species are provided.

Highlights

Plazia Ruiz & Pav. (Mutisioideae, Asteraceae) is a distinctive genus confined to the Andean Cordillera of Peru, Bolivia, Chile, and Argentina
The genus Plazia was described by Ruiz López and Pavón (1794) and they subsequently published its first species, P. conferta Ruiz & Pav. (1798)
Plazia cheiranthifolia is a rare shruby species apparently confined to the central Chilean region near Coquimbo

Summary

Introduction

Plazia Ruiz & Pav. (Mutisioideae, Asteraceae) is a distinctive genus confined to the Andean Cordillera of Peru, Bolivia, Chile, and Argentina. (Mutisioideae, Asteraceae) is a distinctive genus confined to the Andean Cordillera of Peru, Bolivia, Chile, and Argentina. It is recognized by its suffrutescent and decidedly woody habit with stems to a meter or more. Freire in the tribe Onoserideae, associating it with Plazia, but provided no phylogenetic evidence to support that The distribution of these genera involves the Atacama Desert, the high Andes of central and northern Chile, southern Peru, northwestern Argentina and western Bolivia, the Chaco and Monte Regions, as well as the inter-Andean valleys of central and northern Peru (Cabrera 1951, 1977, Ferreyra 1980, 1995, Moreira-Muñoz and Muñoz-Schick 2007, Luebert et al 2009). Plazia daphanoides Wedd. is the only wideranging species, being recorded from southern Peru and adjacent Argentina, Bolivia and Chile, usually in highelevation, dry sites (Cabrera 1978, Ferreyra 1980, 1995)

Discussion