Urochloa jubata

Vorontsova, Maria S., 2022, Revision of some Malagasy forage grasses and their relatives within Brachiaria, Echinochloa, Moorochloa, and Urochloa, Candollea 77 (2), pp. 199-236 : 228-229

23. Urochloa jubata (F ig. & De Not.) Sosef, F l. Gabon 5bis: 64. 1999.

Panicum jubatum F ig. & De Not. in Agrost. Aegypt. F ragm. 2: 15. 1853. Brachiaria jubata (F ig. & De Not.) Stapf in Oliv., F l. Trop. Afr. 9: 563. 1919.

Holotypus: SUDAN: Cordofan, s.d., Figari s.n. (F I).

Tufted perennial, erect, 0.25–1.2 m high, culms not branched, glabrous. Leaf sheath glabrous. Ligule a ciliate membrane. Leaf blade broadly linear, chartaceous, 5–30 × 0.3–1.7 cm, glabrous on both sides, with bulbous based trichomes on margins at base. Inflorescence racemose, slender, contracted, 5–25 cm long. Racemes 5–10, 1–6 cm long, often curved, on a common axis 3–20 cm long, with no secondary branching, rhachis winged, 1–2 mm wide, margin ciliate with yellow tubercle-based trichomes 2–6 mm long, spikelets imbricate, single, subsessile, in 2 rows. Spikelets elliptic, apically subacute, 2.5–3.8 mm long, yellowish, often with a purple tinge. Lower glume ⅔–¾ as long as spikelet, membranous, apically rounded, 7–11-veined, glabrous, turned towards rhachis. Upper glume as long as spikelet, membranous, 5–7-veined, pubescent. Lower floret male, palea as long as lemma, anthers 3, c. 1.5 mm long. Lower lemma membranous, 5-veined, with a few cross veins, pubescent. Upper lemma subacute, rugulose, shiny, with a minute apical crest.

Distribution and ecology. – This African species seems to be an isolated experimental forage introduction to Madagascar. It has not been seen since the only known collection (F ig. 15).

Notes. – Urochloa jubata can be readily recognised by the yellow cilia on the edges of the rhachis, and long rounded lower glume with 7–11 veins.

Additional specimens examined. – MADAGASCAR. Reg. Itasy [Prov. Antananarivo]: vallée de l’Isaonjo, 10–15 km W d’Ambohitrombo, V.1964, Groene s.n. ( TAN, P).