Panicum perrieri A. Camus

Vorontsova, Maria S., 2018, Revision of the group previously known as Panicum L. (Poaceae: Panicoideae) in Madagascar, Candollea 73 (2), pp. 143-186 : 170

22. Panicum perrieri A. Camus in Bull. Soc. Bot. France 72: 371. 1925.

Lectotypus (designated here): MADAGASCAR. Prov. Fianarantsoa: massif d’Andringitra , III.1921, Perrier de la Bâthie 13694 ( P [ P00224770 ]!; isolectotype: K [ K000244712 ]!, P [ P00224771 ]!, TAN!).

Prostrate perennial, with a small rhizome, branched, the long thin culms rooting at nodes, 15 – 70 cm long, the culms and nodes glabrous. Leaf sheaths glabrous. Ligule a ciliolate membrane. Leaf blades linear, flat, chartaceous, 2 –8 × 0.2– 0.6 cm, drying yellow-green, often reflexed at maturity, glabrous to pubescent on both sides. Panicles terminal, partly or fully exserted, 2–8 cm long, linear to narrowly ovate, a relatively small proportion of the plant, the branches appressed or ascendant, never spreading, glabrous, the spikelets clustered at branch apices, the pedicels 3–5 mm long. Spikelets lanceolate, apically acuminate, 2.5 –3(– 3.2) mm long, with prominent veins, green to purple, opening only partly. Lower glume equalling the spikelet, chartaceous, apically acuminate, 3–5-veined, glabrous or finely pubescent. Upper glume as long as the spikelet, herbaceous, apically acuminate, 7-veined, glabrous or finely pubescent. Lower floret barren, with a reduced palea. Lower lemma herbaceous, 7-veined, glabrous or finely pubescent. Upper lemma somewhat shorter than the lower floret, smooth, shiny, pale.

Distribution and ecology. – Endemic to high elevation central Madagascar, open savanna, forest understory, rocky habitats, often on limestone and gneiss, 950–2400 m ( Fig. 10B ).

Notes. – The leaf shape is somewhat variable. Panicles can open out at maturity. This species is prone to fungal infections which distort the spikelet shape and produce dark coloured globose spikelets.

The lectotype sheet is chosen for its best quality original material annotated by Camus.

This species is illustrated in BOSSER (1969: Fig. 123e-h).

Additional material examined. – MADAGASCAR. Prov. Antananarivo: Manjakatompo, 19.XII.1951, Benoist 1669 ( P [ P01914221 ]) ; la Mandraka , II.1953, Bosser 4902 ( P [ P01914229 ]) ; ibid. loco, II.1953, Bosser 4904 ( TAN) ; Analabe, III.1953, Bosser 5152 ( P [ P02726856 ], TAN) ; ibid. loco, III.1953, Bosser 5187 ( P [ P01914216 ]) ; PK 40 rte d’Anjozorobe , II.1954, Bosser 7255 ( P [ P02309310 ]) ; Faratsiho, I.1955, Bosser 7619 ( P [ P01914223 ]) ; ibid. loco, I.1955, Bosser 7620 ( P [ P01914224 ]) ; Tampoketsa d’Ankazobe , IV.1955, Bosser 7864 ( TAN) ; Ankaratra, XI.1955, Bosser 8669 ( P [ P01914219 ]) ; PK 26 rte Arivonimamo , XII.1955, Bosser 8902 ( TAN) ; Faratsiho , face W de l’Ankaratra , II.1957, Bosser 10791 ( TAN) ; au dessus Manjakatompo , II.1957, Bosser 10802 ( P [ P01914227 ]) ; rte Ambatolampy – Faratsiho , II.1957, Bosser 10839 ( P [ P06795983 ]) ; ibid. loco, II.1957, Bosser 10841 ( P [ P00524459 ]) ; Antongona, I.1960, Bosser 13714 ( P [ P06795917 ], TAN) ; la Mandraka , IV.1960, Bosser 14240 ( TAN) ; PK 28 rte du Sud , XII.1960, Bosser 14917 ( P [ P06768560 , P06768564 ]) ; Nanokely, II.1961, Bosser 15166 ( P [ P01914228 ], TAN) ; au dessus de Manjakatompo , III.1961, Bosser 15276 ( P [ P00524469 ]) ; Nanokely, V.1962, Bosser 16360 ( P [ P06768561 ], TAN) ; Lac Mantasoa, 3.III.1970, Bosser 19991 ( K [ K000805595 ], P [ P02222317 ]) ; Ankaratra , IV.1914, Perrier de la Bâthie 10742 ( P [ P01914218 ]) . Prov. Antsiranana: montagne d’Ambre, VI.1970, Bosser 20353 ( K [ K000805593 ], P [ P02222310 ]) ; Massif de Marivorahona, 18.III.1951, Humbert & Capuron 25654 ( P [ P02225793 ]) ; mount Tsaratanana , Perrier de la Bâthie 16363 ( P [ P01914225 ]) . Prov. Fianarantsoa: Ambatofinandrahana, II.1962, Bosser 15869 ( P [ P02251333 ], TAN) ; Andringitra, IV.1964, Bosser 19498 ( P [ P02307358 ]) ; mont Antety près Antsirabe , 10.II.1895, Forsyth-Major s.n. ( G [ G00418812 ]) ; Papanga , 2.XII.1928, Humbert 6952 ( P [ P01914226 ]) ; Andringitra NP , Andohariana , 22°09'24"S 46°53'19"E, 26.XI.2013, Nanjarisoa et al. 75 ( K, TAN) ; Itremo, Ambatoantrano , 20°34'07"S 46°34'47"E, 16.II.2014, Nanjarisoa et al. 128 ( K, TAN) ; Itremo, Ambatoantrano , 20°33'51"S 46°34'48"E, 14.III.2012, Vorontsova et al. 749 (K, TAN) ; Andringitra NP , at camp 2 , 22°09'09"S 46°53'51"E, 14.XII.2013, Vorontsova et al. 1280 ( TAN) ; Itremo, Ambatoasira , 20°36'44"S 46°34'26"E, 20.V.2014, Vorontsova et al. 1580 ( TAN) . Prov. Toliara: Massif de l’Andohahela , I.1934, Humbert 13568 ( P [ P01914294 ]).

Figures

Fig. 10. – Distribution maps. A. Panicum luridum Hack. (stars), P. manongarivense A. Camus (triangles), P. mitopus K. Schum. (circles) and P. novemnerve Stapf (squares); B. Panicum palackyanum A. Camus (stars), P. perrieri A. Camus (triangles), P. pleianthum Peter (circles) and P. spergulifolium A. Camus (squares).