Xyris roraimae

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Xyris roraimae


Tall, often solitary or in small tufts, brittle perennial, to 100 cm high or more, stem short, whole plant with yellowish tints, foliage including scapes papillose-rugulose. Leaves erect or ascending, 20-40 cm, sheath abruptly dilated, there castaneous, ciliate, eligulate or with short (less than 0.5 mm) ligule, blade flattened, 3-5 mm wide, margins pale-ciliate and tuberculate. Scapes distally flattened, 2-3 mm wide, 2flat ribs making pale-ciliate edges; spikes broadly ovoid, ellipsoid or cylindric, 1-3 cm, pale red-brown or yellow-tan, bracts numerous in a spiral, lacking dorsal area and with narrow but distinctive, reddish, scario-lacerate margins; empty bracts several, grading larger into the flowering ones, these broadly obovate to suborbicular, 5-7 mm, ecarinate. Lateral sepals free, very inequilateral, curved, 5.5-6.5 mm, keel broad, lacero-fimbriate or ciliate from about middle to tip; petals obovate, ca. 5 mm; staminodes bearded; anthers 2 mm long. Capsule 2.5-3 mm, placentation basal, valves eseptate; seeds ellipsoid-cylindric, ca. 1 mm, amber.


Brazilian Planalto present, SE and SC Bolivar present, SW Guyana present, Southern America: Brazil Northeast (Bahia present); Brazil Southeast (Minas Gerais present); Brazil West-Central (Goiás present); Venezuela (Venezuela present), contiguous Amazonian Brazil present
SE and SC Bolivar, Venezuela E into SW Guyana and in contiguous Amazonian Brazil, disjunct in the Brazilian Planalto (Bahia, Goias, Minas Gerais).


This species is one of the rare examples of montane Xyris with a bicentric distribution in South America, numerous populations of it recently found in central Brazil.