Urochloa eminii (Mez) Davidse

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 : 226-227

20. Urochloa eminii (Mez) Davidse in Monogr. Syst. Bot. Missouri Bot. Gard. 45: 1258. 1993.

Panicum eminii Mez in Bot. Jahrb. Syst. 34: 135. 1904. Brachiaria eminii (Mez) Robyns in Bull. Jard. Bot. État Bruxelles 9: 176. 1932.

L ectot y pus (d e s i g n a t e d b y R O B Y N S,1 9 3 2: 1 7 7): TANZANIA. Mwanza Reg.: Muansa , V.1892, Stuhlmann 4663 ( B; isolecto-: BR [ BR0000008756312 ] image!, K [ K000282133 ]!) .

= Brachiaria decumbens Stapf in Oliv., F l. Trop. Afr. 9: 528.1919. Urochloa decumbens (Stapf) R.D. Webster, Austral. Paniceae: 234. 1987. Lectotypus (designated by SOSEF, 2016: 360): UGANDA. Kampala: Mengo Distr. , Mpumu, X.1914, Dümmer 1070 (K [ K000282130 ]!; isolecto-: BM [ BM000923187 ]!, BOL [ BOL139359 ] image!, BR [ BR0000008639684 ] image!, PRE [ PRE0664142 -0] image!).

= Brachiaria ruziziensis R. Germ. & C.M. Evrard in Bull. Jard. Bot. État Bruxelles 23: 373. 1953. Urochloa ruziziensis (R. Germ. & C.M. Evrard) Crins in J. Arnold Arbor., Suppl. Ser. 1: 269. 1991. Holotypus: DEMOCRATIC REPUBLIC OF THE CONGO: plaine de la Ruzizi, Tsimuka, II.1950, Germain 6214 (BR [ BR0000008756558 ] image!; iso-: EA [ EA000000400 ] image!, YBI [ YBI143266063 ] image!).

Stoloniferous perennial, largely erect, to 0.3–2 m high, culms weakly branched, rooting at lower nodes, glabrous to sparsely hirsute. Leaf sheath glabrous to pilose. Ligule a ciliate membrane. Leaf blade broadly linear to narrow-lanceolate, chartaceous, 5– 20 × 0.7–1.5 cm, pilose on both sides. Inflorescence racemose, stout, open, 5–20 cm long. Racemes 2–7, 1– 5 cm long, often curved, roughly even in length, on a common axis 1–8 cm long, with no secondary branching, rhachis subfoliaceous, 2–3.5 mm wide, margin ciliate with trichomes 1.5–3 mm long, spikelets imbricate, single, subsessile, usually in 2 rows. Spikelets plump elliptic to obovate, apically subacute, 4–5 mm long, white-yellowish, often with a purple tinge. Lower glume ⅓– ½ as long as spikelet, membranous, clasping, acute or obtuse, 5-veined, glabrous, separated from rest of spikelet by a short internode, turned towards rhachis. Upper glume almost as long as spikelet, membranous, not shining, 5–7-veined, pubescent. Lower floret male, palea as long as lemma. Lower lemma membranous, not shining, 5–7-veined, pubescent. Upper lemma acute, smooth to finely rugulose, with a minute apical crest.

Distribution and ecology. – Introduced trial forage which does not seem to have gained widespread use or become naturalised; all known collections cite its introduced origin. Included here for completeness (F ig. 13).

Notes. – We follow SOSEF (2016) and accept Urochloa eminii , U. decumbens (Stapf) R.D. Webster, and U. ruziziensis (R. Germ. & C.M. Evrard) Crins as representing a single species; all records known from Madagascar were previously placed in U. ruziziensis . Diagnostic characters of the known Malagasy specimens of U. eminii include herbaceous upper glume and lower lemma (shiny cartilaginous upper glume and lower lemma in U. brizantha ), wide rhachis (narrow rhachis in U. brizantha ), and stoloniferous habit (tufted habit in U. brizantha ), although all of these intergrade into U. brizantha .

Additional specimens examined. – MADAGASCAR. Reg. Alaotra-Mangoro [Prov. Toamasina]: introduit du Cogo Belge , Station Agricole Lac Alaotra, VI.1955, Bosser 8146 ( P). Reg. Analamanga [Prov. Antananarivo]: Antananarivo Ville , Ivato , 16.IX.2000, Allorge 2531 ( P). Reg. Bongolava [Prov. Antananarivo]: Kianjasoa , introduit, pasturage, 19.IV.1962, Boudet 1156 ( P) .