Trichanthecium brazzavillense (Franch.) Zuloaga & Morrone in Syst. Bot. Monogr. 94: 21. 2011

Vorontsova, Maria S., 2018, Revision of the group previously known as Panicum L. (Poaceae: Panicoideae) in Madagascar, Candollea 73 (2), pp. 143-186 : 182

30. Trichanthecium brazzavillense (Franch.) Zuloaga & Morrone in Syst. Bot. Monogr. 94: 21. 2011 .

. ≡ Panicum brazzavillense Franch. in Mem. Soc. Hist. Nat Autun 8: 341. 1895.

Holotypus: DEMOCRATIC REPUBLIC OF THE CONGO: env. de Brazzaville , IX.1887, Thollon 876 ( P [ P00057688 ]!; isotype: K [ K000255588 ]!, P [ P00057689 ]!).

= Panicum fredericii Rendle, Cat. Afr. Pl. (Hiern) 2: 180. 1899 . Lectotypus (designated by ZULOAGA et al., 2011: 21): ANGOLA: Pungo Andongo , s.d., Welwitsch 2872 ( K [ K000282489 ]!; isolectotype: BM [ BM000923104 ] image seen, LISU [ LISU226248 , LISU226246 , LISU226247 ] images seen).

= Panicum decaryanum A. Camus in Bull. Soc. Bot. France 99: 65. 1952 . Holotypus: MADAGASCAR. Prov. Fianarantsoa: env. d’Ambatofinandrahana , 17.II.1938, Decary 13013 ( P [ P00450263 ]!), syn. nov.

Erect caespitose perennial, 20–70 cm tall, the culms glabrous or sparsely pubescent on nodes. Leaf sheaths glabrous. Ligule membranous, truncate. Leaf blades filiform, rolled, firm, 5–15 × 0.1–0.2 cm, drying green-brown, basally sparsely pilose above. Panicles terminal, fully exserted, 5–10 cm long, ovate, the branches wiry, appressed to spreading, glabrous, the pedicels filiform and undulating, 2–10 mm long. Spikelets subglobose to ovate, apically acute, 1.5–1.8 mm long, usually purple or brown, gaping open at maturity. Lower glume 3/4–4/5 as long as the spikelet, obtuse to acute, with hyaline edges, 3–5-veined, pilose separated from the rest of the spikelet by an internode of c. 0.3 mm. Upper glume as long as the spikelet, herbaceous, 5-veined, pilose. Lower floret male, with palea. Lower lemma herbaceous, 5-veined, glabrous. Upper lemma shorter than the lower floret dull, finely verruculose, the small verruccae difficult to see without a microscope.

Distribution and ecology. – Tropical African species; distribution in Madagascar limited to open seasonally flooded and grazed grassland and tapia forest on the High Plateau, 800–1800 m ( Fig. 16B ).

Notes. – Recognisable by its filiform leaves, pilose spikelets, and a lower glume almost as long as the spikelet. The panicle resembles the sympatric Panicum ibitense and can be distinguished from that species by its erect tufted habit, basal leaves, and a lack of swollen underground storage organs.

This species is illustrated by BOSSER (1969: Fig. 119a-d as Panicum decaryanum ) and by ZULOAGA et al. (2011: Fig. 8 ).

Additional material examined. – MADAGASCAR. Prov. Antananarivo: Analabe , III.1953, Bosser 5140 ( P [ P02608840 ]) ; ibid. loco, III.1953, Bosser 5144 ( K [ K000805464 ], P [ P02608843 ], TAN) . Prov. Fianarantsoa: Itremo , I.1964, Bosser 18946 ( P [ P02608823 ]) ; ibid. loco, I.1964, Bosser 18946bis ( P [ P02608825 ]) ; ibid. loco, I.1964, Bosser 18952 ( P [ P02608842 ], TAN) ; ibid. loco, I.1964, Bosser 18952bis ( P [ P02608826 ]) ; ibid. loco, IV.1964, Bosser 19540 ( K, P [ P02608822 ]) ; Col de Itremo , 27.I.1975, Croat 29817 ( TAN) ; Itremo, Ianasana , 20°34'39"S 46°34'59"E, 15.III.2013, Nanjarisoa & Andriamampionona 9 ( K, TAN) ; Itremo, Ampangabe , 20°37'02"S 46°36'49"E, 15.II.2014, Nanjarisoa et al. 115 ( K, TAN) ; Itremo, Ambatoantrano , 20°34'77"S 46°34'50"E, 16.II.2014, Nanjarisoa et al. 126 ( K, TAN) ; Itremo, Ankevo , 20°39'35"S 46°34'46"E, 13.III.2012, Ratovonirina et al. 193 ( K [ K000753883 ], TAN) . Prov. Toamasina: Mahatsinjo , XII.1954, Bosser 7475 ( P [ P02307362 ]) ; lac Alaotra , VI.1959, Bosser 13043 ( P [ P02608824 ], TAN).

Figures

Fig. 16. – Distribution maps. A. Panicum subalbidum Kunth (stars), P. subhystrix A. Camus (triangles), P. trichocladum K. Schum. (circles) and P. voeltzkowii Mez (squares); B. Panicum vohitrense A. Camus (stars), Trichanthecium brazzavillense (Franch.) Zuloaga & Morrone (triangles), T. parvifolium (Lam.) Zuloaga & Morrone (circles) and Urochloa maxima (Jacq.) R.D. Webster (squares).

Fig. 8. – Distribution maps. A. Panicum cupressifolium A. Camus (stars), P. danguyi A. Camus (triangles), P. dregeanum Nees (circles) and P. flacourtii A. Camus (squares); B. Panicum humbertii A. Camus (stars), P. humile Nees ex Steud. (triangles), P. ibitense A. Camus (circles) and P. inconspicuum Voronts. (squares).