Distribution and diagnostic characters of Nassella (Poaceae: Stipeae)

Abstract

Summary Barkworth, M. E. & Torres, M. A.: Distribution and diagnostic characters of Nassella (Poaceae: Stipeae). – Taxon 50: 439–468. 2001. – ISSN 0040‐0262. Nassella sensu lato includes 116 species, making it one of the largest genera in tribe Stipeae. Argentina has the largest number of species, 72, with the greatest concentration being in the northwestern part of the country. Bolivia, Chile, and Uruguay have 26, 27, and 27 species, respectively. Other South American countries in which the genus is present are Brazil (18 species), Colombia (8), Ecuador (9), Paraguay (4), Peru (18), and Venezuela (2). Guatemala has two species, but Costa Rica only one. Mexico has eight native species, five of which also grow in the United States. One additional species grows in both the United States and Canada. Sixty species are known only from one country; one species, N. mexicana, grows in eight countries. Several new distribution records are documented: N. caespitosa, N. elata, N. leptothera and N. punensis for Bolivia, N. pauciciliata and N. spegazzinii for Brazil, N. airoides, N. argentinensis, N. spegazzinii for Paraguay, and N. tucumana (= N. asperifolia) for Peru. Three new combinations are presented: N. burkartii, N. ligularis, and N. quinqueciliata. Two recently transferred species, N. barrancaensis and N. brachychaeta, are excluded from the genus and N. asperifolia, N. bonariensis, and N. amethystina are placed in synonymy. Tables summarising the distribution of Nassella and its morphological variation are presented.

Nonindigenous Plant Advantage in Native and Exotic Australian Grasses under Experimental Drought, Warming, and Atmospheric CO2 Enrichment

“…Examination of specimens from across Australia also suggests that coronal morphology exists as a continuum rather than as discrete groups, and indeed most morphological characters appear to overlap in both species [52]. Corona lengths ranged from 1.2–2.1 mm long in the four populations studied in this paper, suggesting possible affiliation with N. leucotricha sensu [52]; (but see [51] and [54]). Due to the poor current circumscription of the two species in Australia, and for consistency with the existing literature, in this paper were refer to all populations as Nassella neesiana sens.…”

“…Recently, however, some have been re-identified as N. leucotricha sensu [51], primarily on the basis of length of the seed corona (>1.5 mm and <1.5 mm in N. leucotricha and N. neesiana respectively). However, in Australia and possibly in the Americas there is a lack of clarity regarding the morphological distinctiveness of these species, and taxonomic treatments contain some inconsistencies (c.f., [52,53,54]) that makes accurate identification difficult.…”

“…0.5–1 mm; [52]). Examination of specimens from across Australia also suggests that coronal morphology exists as a continuum rather than as discrete groups, and indeed most morphological characters appear to overlap in both species [52].…”

“…0.5–1 mm; [52]). Examination of specimens from across Australia also suggests that coronal morphology exists as a continuum rather than as discrete groups, and indeed most morphological characters appear to overlap in both species [52]. Corona lengths ranged from 1.2–2.1 mm long in the four populations studied in this paper, suggesting possible affiliation with N. leucotricha sensu [52]; (but see [51] and [54]).…”

An anatomo-ecological experiment in Austrostipa aristiglumis, a lowland Stipoid species

“…The species grow primarily in temperate or warm-temperate regions, and are dominant in many of the arid grasslands of southern Australia, South America, and Asia at varying elevations (0 -5000 m) and the ecological range includes arid, semiarid, semihumid and humid habitats (Barkworth & Torres 2001).…”