Paspalum cerradoense R.C. Oliveira & Valls, 2015

Oliveira, Regina Célia De, Valls, José F. M., Gomes, Sueli Maria, Fagg, Christopher W. & Pozzobon, Marisa Toniolo, 2015, A new species of Paspalum, Notata group (Poaceae, Paspaleae), from the Cerrado biome, Brazil: description, chromosome number, and leaf blade anatomy, Phytotaxa 203 (2), pp. 159-168 : 160-164

Paspalum cerradoense R.C. Oliveira & Valls , sp. nov. ( Fig. 1 )

Ligules ca. 0.3 mm, blades papillose-pilose on both surfaces, hairs 3–5 mm long, blades with base slightly narrow, apex acute, rachis 1.3–4.5 cm long, spikelets broadly ovate, upper glume winged, without wrinkles, anthers yellow.

Type:— BRAZIL. Goiás: Cavalcante, “Reserva Particular Natural Serra do Tombador” (RPPN), cerrado rupestre, 779 m, 13º40’39.6”S, 47º49’25.5”W, 31 October 2011, R.C. Oliveira, A. S. Silva, A.R.O. Ribeiro, P.R.F. Amorim & A.S. Lima 2693 (holotype UB!, isotypes CEN!, MO!).

Caespitose perennial herb; with very short and cylindrical rhizomes; culms 34.5–105 cm tall, ca. 1.2 mm diam., erect; internodes and nodes glabrous. Leaf sheaths longer than the internodes, pilose or glabrous, margins of leaf sheaths papillose pilose in immature plants, hairs ca. 1.8 mm long; ligules reduced, ca. 0.3 mm, membranous, rounded, hyaline; few dorsal hairs contiguous to the ligule; auricles absent; collar pilose, discontinuous by the midrib or indistinct; blades 15–18 × 0.5–0.6 cm, lanceolate, flat, olive green, papillose-pilose on both surfaces, hairs 3–5 mm long; base slightly narrower than the sheath; apex acute, margins finely scabrous. Inflorescences terminal, long exserted or inserted; pulvini pilose; racemes conjugated (or eventually single), divergent and erect, 1.3–4.5 cm long; rachis ca. 0.6–0.8 mm wide, glabrous or pilose, greenish, with very small wings, ending in a spikelet, occasionally aborted; pedicels normally unbranched bearing solitary spikelets, some occasionally branched, presenting an aborted spikelet, ca. 0.5 mm long, pilose. Spikelets solitary, occasionally in pair with one aborted spikelet, 4.7–4.9 × 2.5–2.8 mm, elliptic-ovate to broadly ovate, green or light brown at maturity, bi-seriate, compactly imbricate along the rachis, dorsiventrally compressed; lower glume absent or, rarely, nearly obsolete in some spikelets; upper glume 4.7–4.9 × 2.5–2.7 mm, about 0.03–0.06 mm longer than the upper anthecium, papyraceous, the margin winged, not or rarely wrinkled, glabrous or with few hairs on the dorsal surface, apex acute, usually with two to four apical teeth, 5-nerved, two marginal nerves on the wings; lower lemma 4.7–4.8 × 2 mm, papyraceous, 5-nerved, glabrous, not or rarely corrugate; apex attenuate; upper anthecium 4 × 1 mm, 0.03–0.06 mm less than the upper glume length, crustaceous, lightly papillose, narrowly ellipsoid, pale, glabrous; stamens 3, anthers ca. 2.3 mm, yellow. Caryopsis not seen.

Paratype:— BRAZIL. Goiás: Cavalcante, “Reserva Particular Natural (RPPN) Serra do Tombador”, about 5 km from the Center, area recently burnt, 1.5 km from the type collection, in a hilly area, growing in sand between rocky outcrops, locally frequent caespitose herb, 13º40’39.1”S, 47º50’14.2”W, 8 December 2012, R.C. Oliveira & C.W. Fagg 2787 (UB!, CEN!).

Etymology:— The epithet of the new species refers to the Cerrado biome, a neotropical environment mostly dominated by the savannah physiognomy, that covers some 20% of the Brazilian territory.

Distribution and habitat:— The species has been found in open savannah, on sandy-rocky soils, so far only in the “RPPN Serra do Tombador” area, Goiás, Brazil. At both of the collection sites, the species was found flowering after seasonally common natural fires ( Fig. 2 ).

IUCN Red List category:— Paspalum cerradoense is only known from “RPPN Serra do Tombador”, in legally conserved areas. Although the two documented occurrences have restricted distributions, and no further searching has yet been conducted, there is no evidence of population decline at these sites or of a possible threat of extinction. This RPPN is in the “Chapada dos Veadeiros” region, which has several protected areas, including a National Park inside the Cerrado Biosphere Reserve of Goiás. Paspalum cerradoense fits in the Data Deficient (DD) category, following the IUCN Red List criteria ( IUCN 2001).

Chromosome number:— Paspalum cerradoense has 2n=20 chromosomes ( Fig. 3 ).

Figures

FIGURE 1. Paspalum cerradoense R.C. Oliveira & Valls. A. Habit. B. Inflorescence.A. Habit. B. Inflorescence. C. Segment of rachis with pedicels. D. Ligule region. E. Upper glume, detail of the subapical teeth in dorsal view. F. Upper glume, ventral view. G. Spikelet, dorsal view, showing upper glume. H. Spikelet, ventral view, showing lower lemma. I. Upper anthecium, ventral view. J. Upper anthecium, dorsal view.

FIGURE 2. Distribution map of Paspalum cerradoense in the Cerrado biome, Brazil.

FIGURE 3. Chromosomes of Paspalum cerradoense R.C. Oliveira & Valls, Oliveira & Fagg 2787 (paratype). Scale: 10 μm.