Jarava

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.

Abstract: Piptochaetium (Poaceae, Pooideae, Stipeae) is a New World genus of grasses distributed primarily in temperate South America, with several species extending into Central and southern North America. The genus comprises 36 species and 2 varieties. Morphological synapomorphies for the genus include involute lemma margins that fit into the palea groove, a bi-keeled palea longer than the lemma and protruding from the lemma apex, and fundamental cell sidewalls that are regularly dentate. The closely related genera Nassella (116 species) and Jarava (59 species) are also primarily South American, with a few species found in Central and North America. Published molecular studies to date have focused upon generic-level relationships within the tribe Stipeae, but none have included more than a few representatives of each genus. We present here results of phylogenetic analyses of these genera based upon combined DNA sequences of both nuclear (ITS) and cpDNA (rpl16, trnL-F) markers. Piptochaetium is supported as monophyletic in all studies, whereas Nassella is recovered as monophyletic only if Jaravaplumosa is included. Infrageneric relationships ofPiptochaetium are also compared to a recent morphological phylogeny of the genus.

Abstract: In the catalogue of vascular plants of Chile, 3 genera in the tribe Stipeae are cited: Nassella s.str., Piptochaetium y Stipa s.l. (incl. Ortachne). New morphological characters primarily these of spikelets, anatomical leaves, embryological characters, epidermis patterns of lemma and molecular data have lead to a more natural delimitation of genera of the tribe Stipeae (Pooideae, Poaceae). At present, the tribe Stipeae in Chile is represented by 5 genera: Anatherostipa (Hack. ex Kuntze) Penail. (4 spp.); Jarava Ruiz et Pav. (22 spp.); Nassella (Trin.) E.Desv. s.l. (26 spp.); Ortachne Nees ex Steud. (2 spp.); and Piptochaetium J.Presl (2 spp.). Besides, the Piptatherum genus is represented by P. miliaceum (L.) Cosson, an adventitial species. A historical consideration, description, and a list of their species (basyonym and synonyms) are listed for each genus. For practical purposes, references for species identification are cited. A key for Chilean genera is presented.

Abstract: Cialdella, A. M. 2010. Nomenclatural novelties in the tribe Stipeae (Poaceae, Pooideae) for the Argentine- an flora. Darwiniana 48(2): 168-174. During the revision of the Stipeae (Poaceae) for the Argentinean flora and in accordance to the latest phylogenetic studies in the tribe, it became necessary to transfer some recently described taxa from the genus Stipa to Nassella, Jarava or Pappostipa. As a result, 12 new combinations are here proposed: Jarava ichu var. pungens, Nassella brachyglumis, N. macrotricha, Pappostipa arenicola, P. choconen- sis, P. colloncurensis, P. frigida var. longifolia, P. jucunda, P. kieslingii, P. mapuche, P. marqueziana and P. zulmae. A key to identify the genera of Stipeae in Argentina is also included.