THE GENUS JARAVA RUIZ ET PAV. (STIPEAE-POACEAE): DELIMITATION AND NEW COMBINATIONS

Abstract

Jarava Ruiz et Pav. is recognized as South American genus. This genus would include all those species treated frequently as Stipa L. s.l. according to South American agrostologists. Even if different morphological structure can be identify, is important and common in this genus that anthoecia showed morphological characters for a wind dispersion (Stipa subgenus Jarava, Stipa subgenus Ptilostipa and Stipa subgenus Pappostipa). Long hairs at the top of the lemma (pappus) or plumose awns are interpreted as evolutionary novelty. These structures are considered advanced characters for a wind dispersion of diasporas. Species with axillaries aerial cleistogamy should be also included in Jarava. Under this considerations a new delimitation for the genus and new combinations are realized.