First record of Ehrharta longiflora Sm . ( Poaceae , Ehrharteae ) for South America

Ehrharta longiflora Sm. (Poaceae) is recorded for the first time in South America. A few naturalized populations were located in disturbed areas of Valparaíso (Central Chile). A brief taxonomic discussion, images, and a location map of the new record of this African grass are provided here.


Introduction
Ehrharta Thunb.(Poaceae, Ehrharteae) is a grass genus embracing approximately 35 species (Clayton andRenvoize 1986, Fish et al. 2015).They are annual or perennial plants, characterized by displaying pedicellate solitary spikelets arranged on racemose or paniculiform inflorescences (rarely a single spikelet).Each spikelet has 3 florets, the lower 2 sterile and reduced to lemmas and the upper 1 bisexual (usually smaller than lower 2).The glumes are 5-to 7-nerved, and the sterile lemmas (lower 2) are usually larger and different from bisexual lemma (upper one).The ligules are membranaceous or composed of hairs, and the caryopses are elliptic and laterally compressed.
The genus Ehrharta is naturally distributed from southern Africa to Ethiopia and Yemen (Fish et al. 2015).Some species are naturalized in Indonesia, New Zealand, Australia, western Mediterranean Basin, western North America, and South America (Edgar et al. 1991, Barkworth 2007, Rúgolo 2012, Fish et al. 2015, Euro+Med 2006-).In North America 3 species are established in California-E.calycina Sm., E. erecta Lam., and E. longiflora Sm. (Barkworth 2007)-whereas in South America only E. villosa J.H. Schult.was reported from a restricted area of the Atlantic coast of Buenos Aires, Argentina (Rúgolo 2012).
Due to ongoing floristic studies in Valparaíso and its peri-urban areas (Central Chile), we located a few naturalized populations of E. longiflora, which represents the first report of this alien species for South America (Fig. 1).These populations occur in disturbed areas such as wastelands and roadsides, along with other naturalized species, for example Carduus pycnocephalus L., Chrysanthemum coronarium L., Hordeum murinum L., Lolium multiflorum Lam., Parietaria judaica L., and Tropaeolum majus L. So far, it is uncertain when this weed arrived in Valparaíso, but new findings would contribute to elucidate this issue.

Methods
We used Clayton and Renvoize (1986) and Fish et al. (2015) to identify the collected specimens of the new finding.Qualitative characters were studied directly by eye or with the aid of binocular lenses, while the quantitative characters were recorded using a Mitutoyo digital caliper, CD-15DC.Figures were edited using software Adobe Photoshop CS6 (Adobe Systems Incorporated) and the map was produced in QGIS 2.14.20 (QGIS Development Team).The herbarium specimens were deposited at SGO and CONC (acronyms follow Thiers 2017).

Results
Ehrharta longiflora Sm., Pl.Icon.Ined.2: pl.32.1790.Figure 2 Leafy erect annual.Culms 40−75 cm, often geniculate basally.Leaf-sheaths obviously nerved, keeled, submembranaceous, glabrous or almost so; auricles ciliate; ligules ca 2.5 mm, lacerate; leaf-blades 4.5−25 cm long, 0.5−0.9cm wide, flat, usually with some scattered submarginal trichomes, margins scaberulous.Inflorescence paniculiform, 10−24 cm long, erect, narrow, with branches usually ± pendulous; pedicels filiform.Spikelets 15−27 mm long including the awns.Glumes unequal, ca 1/3 as long as the spikelet, membranaceous, usually purple-coloured.Sterile lemmas similar, indurate, hispidulous upward, with tufted hairs at the base, conspicuously awned at the apex (awns 6−17 mm long, hispidulous); upper sterile lemma with a short hingelike appendage at the base.Bisexual lemma glabrous or almost so, unawned.Caryopses ca 4.4 mm long, 1.5 mm wide, elliptic, laterally compressed.Specimen examined.CHILE.Valparaíso Region: Valparaíso, cerro San Juan de Dios, 33°03ʹ09ʺ S, 071°37ʹ32ʺ W, 90 m, 03 Oct. 2017, J. Calvo 7585 (SGO, CONC).Ehrharta longiflora is native to western South Africa (Fish et al. 2015), and it is a naturalized weed in southern Australia, New Zealand, California, and Gran Canaria of the Canary Islands (Acebes et al. 2004).This species was also reported in Belgium (Auquier 1980) and Catalonia (Casasayas 1989), but it seems that these populations remain in confined areas.The presence of this species in Chile has been detected for the first time in 2017 (Fig. 1).The few known populations still only occur in urban areas, which lead us to think that it is a recent introduction.However, the invasive potential registered in southern Australia and California, where the climate is similar to Central Chile, alerts that its spreading might be quick.

Figure 1 .
Figure 1.Location of the new record of Ehrharta longiflora in Chile (Valparaíso).