Agrostis meyenii Trin. (Poaceae, Agrostidinae): first records from Peru, including taxonomic notes and an identification key

Steven P Sylvester,Mitsy D.P.V Sylvester

doi:10.15560/.16.5.1347

Abstract

The grass Agrostis meyenii Trin. (Poaceae, Agrostidinae) is newly recorded from Peru and is found in high-Andean puna grasslands of the departments of Ancash, Ayacucho, and Hu&aacute;nuco, marking the northernmost known limit of this species. A revised species description, images, taxonomic notes, and a key are also presented to differentiate A. meyenii from similar species in Peru with congested, spike-like panicles and absent or reduced (measuring less than &frac12; the length of the lemma) paleas (i.e., A. breviculmis Hitchc., A. foliata Hook.f., and A. tolucensis Kunth).

Highlights

The grass genus Agrostis L. belongs to tribe Poeae R.Br., subtribe Agrostidinae Fr. (Soreng et al 2017) and is morphologically defined by taxa with membranous ligules, paniculate inflorescences composed of one-flowered, laterally compressed spikelets, glumes usually amply surpassing the florets, florets lacking a rachilla extension emerging from under the palea, and calluses glabrous or short pilose, among other characteristics
The species was previously known from high-elevation puna grassland and pampa of Argentina, Chile (Rúgolo de Agrasar 2012), and Bolivia (Renvoize 1998; Jørgensen et al 2014) (Fig. 2)
The species is found further south in Peru, in the Lucanas province of Ayacucho department, and it is likely to extend across the puna grassland biome of the central Andes, but has so far been unrecorded

Summary

Introduction

The grass genus Agrostis L. belongs to tribe Poeae R.Br., subtribe Agrostidinae Fr. (Soreng et al 2017) and is morphologically defined by taxa with membranous ligules, paniculate inflorescences composed of one-flowered, laterally compressed spikelets, glumes usually amply surpassing the florets, florets lacking a rachilla extension emerging from under the palea, and calluses glabrous or short pilose, among other characteristics. With the addition of A. meyenii, and including taxa previously circumscribed in Bromidium based on indications from recent phylogenetic research (Tkach et al 2020), it is currently estimated that 13 species of Agrostis are present in Peru (A. breviculmis Hitchc.; A. foliata Hook.f.; A. gigantea Roth; A. hyemalis (Walter) Britton, Sterns & Poggenb.; A. imberbis Phil.; A. koelerioides É.Desv.; A. mertensii Trin.; A. meyenii; A. perennans (Walter) Tuck.; A. stolonifera L.; A. subrepens (Hitchc.) Hitchc.; A. tandilensis (Kuntze) Parodi; A. tolucensis Kunth) (Davidse et al 1993; Tovar 1993; Soreng et al 2003 and onwards; Plants of the World Online 2020; Sylvester et al 2020a). A taxonomic reappraisal of Peruvian Agrostis is urgently needed, with our research contributing to this

Methods

Results

Discussion