Panicum voeltzkowii Mez

Vorontsova, Maria S., 2018, Revision of the group previously known as Panicum L. (Poaceae: Panicoideae) in Madagascar, Candollea 73 (2), pp. 143-186 : 180-181

28. Panicum voeltzkowii Mez in Bot. Jahrb. Syst. 57: 187. 1921 ( Fig. 13B ).

Lectotypus (designated here): MADAGASCAR. Prov. Antsiranana: Baie de Rigny, X.1848, Boivin 2266 ( P [ P00450240 ]!; isolectotype: K [ K000805591 ]!, G [ G00378071 , G00378072 ] images seen, P [ P03367593 ]!, US, W [ W18890147243 ] image seen) . Syntypus: MADAGASCAR: sine loco, Voeltzkow 321 (not found) .

= Panicum mandrarense A. Camus in Bull. Soc. Bot. France 99: 63. 1952 . Lectotypus (designated here): MADAGASCAR. Prov. Toliara: montagnes entre l’Andohahela et l’Elakelaka , entre Ampahiso et Mahamavo , I.1934, Humbert 13783 ( P [ P00450230 ]!; isolectotype: P [ P00450231 , P02207804 ]!, US) . Syntypus: MADAGASCAR. Prov. Toliara: Mandrare valley, Anadabolava, Humbert 12549 (not found), syn. nov .

= Panicum pseudowoeltzkowii A. Camus in Bull. Soc. Bot. France 105: 248. 1958 . Lectotypus (designated here): MADAGASCAR. Prov. Toliara: Manampetsotsa au Delta de la Linta, 17.VIII.1928, Humbert & Swingle 5345 ( P [ P00450248 ]!; isolectotype: NY, P [ P00450249 , P02608146 ]!, TAN!, US [3 sheets]!) . Syntypus: MADAGASCAR. Prov. Toliara: Manampetsotsa au delta de la Linta , 17.VIII.1928, Humbert & Swingle 5302 ( P [ P02608148 ]!), syn. nov .

= Panicum pseudowoeltzkowii var. latifolium A. Camus in Bull. Soc. Bot. France 105: 248. 1958 . Lectotypus (designated here): MADAGASCAR. Prov. Toliara: du Lac Manampetsa près d’Itampolo , 17.VIII.1928 – 24.VIII.1928, Humbert & Swingle 5388bis ( P [ P00450250 ]!) . Syntypus: MADAGASCAR. Prov. Mahajanga: env. de Marovoay , XII.1903, Perrier de la Bâthie 11100 ( P [ P02207800 ]!) , syn. nov.

= Panicum morombense A. Camus in Notul. Syst. (Paris) 15: 412. 1959 . Holotypus: MADAGASCAR. Prov. Toliara: Morombe, 24.II.1943, Decary 18765 ( P [ P00450234 ]!) , syn. nov.

Caespitose perennial, forming stolons and rooting at nodes, the plant tufted or geniculately ascending or creeping, 10–40 cm tall, the culms glabrous. Leaf sheaths glabrous. Ligule a line of hairs. Leaf blades linear to lanecolate, flat or rolled, chartaceous, 3–9 × 0.15–0.7 cm, drying yellow-green, glabrous to sparsely pubescent on both sides, often with bulbous based cilia on the lower part of the margin. Panicles terminal, fully exserted, 2.5–6 cm long, ovate, the branches lax, ascending, glabrous. Spikelets ovate to subglobose, apically obtuse, 1.3–1.7 mm long, pale brown or purplish, gaping open at maturity. Lower glume c. ½ as long as the spikelet, keeled, apically finely acuminate, 3-veined, finely scabrous on the keel. Upper glume as long as the spikelet, herbaceous, 5-veined, glabrous. Lower floret male, with palea. Lower lemma herbaceous, 5-veined, glabrous. Upper lemma smooth, shiny, pale.

Distribution and ecology. – Endemic to Madagascar and nearby islands. Southern and western areas of Madagascar, especially on the coast and at low elevations on sand, common along roadsides, pastures, secondary vegetation, grasslands, dunes, and spiny forest, 0–500 m ( Fig. 16A ). Common on the coast of La Réunion.

Notes. – Panicum voeltzkowii commonly forms ground cover in arid southern Madagascar. Clearly a relative of P. luridum , this species occupies a more arid habitat niche; the spikelets are smaller than P. luridum and apically rounded. The long-standing distinction between P. voeltzkowii (tufted with no stolons, salt tolerant) and P. pseudowoeltzkowii (stoloniferous, not salt tolerant) is not possible to differentiate on herbarium specimens; both morphologies have been observed in a single population in the field.

Of the two syntype collections, only Boivin 2266 was successfully located. The lectotype sheet is selected because it represents the top set of Boivin’s collections held at P, with an original handwritten label. The lectotype of P. mandrarense is selected for its best quality original material annotated by the author. The epithet of P. pseudowoeltzkowii has sometimes been spelled as ‘ Panicum pseudovoeltzkowii’, a variation in transliteration that does not constitute a correctable error. The protologue of P. pseudowoeltzkowii indicates two syntypes from the southwestern coast: Humbert & Swingle 5302, and 5345; the lectotype is chosen because the collection Humbert & Swingle 5345 has better global distribution of duplicates and the lectotype sheet bears the best material annotated by the author. The chosen lectotype sheet of P. pseudowoeltzkowii var. latifolium is the only sheet annotated by A. Camus of the two syntype collections indicated in the protologue: Perrier de la Bâthie 11100 and Humbert & Swingle 5388bis. The type collection of P. morombense is cited in the protologue as “Decary 8765”, almost certainly an erroneous citation of Decary 18765.

This species is illustrated in BOSSER (1969: Fig. 126a-d as ‘ Panicum pseudovoeltzkowii’).

Additional material examined. – MADAGASCAR. Prov. Antsiranana: Fotsimavo, Ambilobe , XII.1964, Morat 1281 ( P [ P 01914239 ]) . Prov. Mahajanga: Majunga , 4.III.1924, Decary 2420 ( P [ P 02207805 ]) ; plage de Marofototra , X.1904, Morat 746 ( P [ P02309297 ]) ; E d’Antsalova , I.1975, Morat 4885 ( TAN) ; baie de Bombetoka , V.1907, Perrier de la Bâthie 11040 ( P [ P02608152 ]) ; près d’Andranomavo , X.1903, Perrier de la Bâthie 11103 ( P [ P 01914247 ]) ; Station Forestière Antsianitia , 15°34'42"S 46°24'55"E, 15.II.2013, Vorontsova et al. 937 ( K, TAN) ; ibid. loco, 15.II.2013, Vorontsova et al. 945 ( K, TAN) ; between Station Forestière Marohogo and Andradia , 15°43'13"S 46°28'39"E, 19.II.2013, Vorontsova et al. 969 ( K, TAN) . Prov. Toliara: Manasoa, Mahafaly , 29. I.1913, Afzelius G45 ( K [ K 000805607 ]) ; Toliara Ville, jardin Griton , V.1930, Basse s.n. ( P [ P 02608158 ]) ; entre Efoetsy et Itampolo , V.1951, Bosser 166 ( P [ P 01914252 , P 06795573 ], TAN) ; Ampanihy-Beloha , V.1951, Bosser 308 ( P [ P 02726818 ], TAN) ; Androka, Ranomasy , V.1951, Bosser 319 ( TAN) ; W d’Ejeda , V.1951, Bosser 407 ( P [ P 01914154 ], TAN) ; Efoetsy , V.1951, Bosser 460 ( P [ P 01914253 ], TAN) ; Ifotaka, Mandrare , XI.1952, Bosser 4203 ( P [ P 02207811 ], TAN) ; Imanombo, XI.1952, Bosser 4298 ( P [ P02608153 , P02726855 ], TAN) ; Ankilizato, Mahabo , I.1953, Bosser 4526b ( P [ P01914251 ], TAN) ; Sakaraha, II.1956, Bosser 9025 ( P [ P01914248 ], TAN) ; env. de Morondava , IX.1956, Bosser 10033 ( P [ P01914249 ]) ; entre Ampanihy et Ejeda , XI.1956, Bosser 10537 ( P [ P01914255 ]) ; vallée du Fiherenana , III.1960, Bosser 14023 ( P [ P01914158 ], TAN) ; Vohitany , bords de la Linta , II.1962, Bosser 15739 ( P [ P01914153 ], TAN) ; Beheloka, 17.III.1962, Bosser & Viennot 16073 ( P [ P01914157 ]) ; Tanandava, Mangoky , III.1962, Bosser & Viennot 16103 ( P [ P02207809 ]) ; PK 20 rte de Ianakafy , près de Betroka , II.1963, Bosser 17210 ( P [ P02307384 ]) ; env. d’Ankazoabo , II.1963, Bosser 17478 ( P [ P01914155 ]) ; Ampanihy-Beloha, S d’Ampanihy , III.1964, Bosser 19218 ( P [ P02726823 ]) ; entre Ampanihy et Tranoroa , III.1964, Bosser 19334 ( P [ P02726817 ]) ; île de Nosy-Ve, au large d’Anakao , II.1964, Bosser 19337 ( P [ P02608155 ]) ; Andavadoaka, III.1964, Chabonis s.n. ( P [ P01914236 ]) ; between Tongobory and Betioky , 23°31'30"S 44°19'30"E, 14.II.1975, Croat 31210 ( TAN) ; Lavanono, 17.II.1975, Croat 31562 ( K [ K000805560 ], P [ P01914254 ]) ; vicinity of Tsihombe , 18.II.1975, Croat 31619 ( TAN) ; Ambovombe, 19.IV.1924, Decary 2561 ( P [ P01914233 ]) ; Antanimora, près du Fort-Dauphin , 12.VII.1926, Decary 4218 ( P [ P02207799 ]) ; Amboasary , 22.I.1932, Decary 9572 ( P [ P03487909 ], TAN, US) ; station Behemboka , Dequaire 27585 ( P [ P02726887 ]) ; S Ambovombé , 1956, Descoings 1635 ( P [ P02726850 ], TAN) ; ibid. loco, 1956, Descoings 1657 ( P [ P02307354 ], TAN) ; Itampolo, IV.1969, Guillaumet 2444 ( P [ P01914250 ]) ; Soaranano, 20.I.1938, Herb. Jard. Bot.Tan. 3122 ( P [ P01914235 ]) ; entre Beloha et Ambovombe , VII.1930, Herb.Jard.Bot.Tan. 261952 ( P [ P01914232 ]) ; delta du Fiherenana, 14.IX.1924, Humbert & Perrier de la Bâthie 2450 ( K [ K000805590 ]) ; plateau Mahafaly , 27.IX.1924, Humbert 2668 ( P [ P02726884 ]) ; delta de la Linta , 24.VIII.1928, Humbert & Swingle 5456 ( US) ; env. de Tsihombe , 8.IX.1928, Humbert & Swingle 5564 ( P [ P00450253 ]) ; vallée de la Manambolo , XII.1933, Humbert 12779 ( P [ P02207821 ]) ; entre Ampahiso et Mahamavo , I.1934, Humbert 13713 ( P [ P01914238 ]) ; env. de Manera , III.1934, Humbert 14419 ( P [ P02207806 ]) ; env. de Manombo , 29.I.1947, Humbert 20062 ( P [ P01914240 ]) ; env. d’Antanimoro , 30–35 km N vers Ambia, 6.II.1955, Humbert & Capuron 28831 ( P [ P03487885 , P03487907 ]) ; baie des Galions , 18.II.1955, Humbert & Capuron 29014a ( P [ P02222306 ], TAN) ; ibid. loco, 18.II.1955, Humbert 29033 ( P [ P01914241 ]) ; ibid. loco, 18.II.1955, Humbert & Capuron 29034 ( P [ P02222307 ]) ; cap Sainte-Marie , 5.III.1955, Humbert & Capuron 29249 ( P [ P01914244 ]) ; lac Tsimanampetsa , 25.XI.1960, Leandri 4056 ( P [ P02309294 ]) ; Sarodrano, II.1967, Morat 2637 ( P [ P01914237 ]) ; Toliary rural , II.1968, Morat 2872 ( TAN) ; Sakaraha, II.1968, Morat 2886 ( TAN) ; Ankaboka – Bemandraty , Ankazoabo , VIII.1967, Morat 2900 ( TAN) ; Sakaraha, IV.1967, Morat 2927 ( TAN) ; lac Tsimanampetsotsa , 15.IV.1961, Peltier & Peltier 3124 ( P [ P02307319 ]) ; entre Tulear et St Augustine , 31.III.1966, Peltier & Peltier 5841 ( P [ P01914151 ]) ; Mahafaly Plateau, Perrier de la Bâthie 114 ( K [ K000805494 ]) ; ibid. loco, Perrier de la Bâthie 119 ( K [ K000805493 ]) ; dunes de la côte Mahafaly , Perrier de la Bâthie 139 ( K [ K000805558 ]) ; plateau Mahafaly , VI.1910, Perrier de la Bâthie 11205 ( P [ P01914149 ]) ; ibid. loco, VI.1910, Perrier de la Bâthie 11206 ( P [ P01914150 ]) ; Antaka, de la côte Mahafaly , Perrier de la Bâthie 11184 ( P [ P01914243 ]) ; dunes des Befanamy , 15.II.1921, Poisson 141 ( P [ P02207810 ]) ; terrain d’aviation , Morondava, 9.III.1953, Portères s.n. ( P [ P06795577 ]) ; SW, V.1953, Portères s.n. ( P [ P02373633 ]) ; Betioky-Ejeda road , 23°52'34"S 44°07'15"E, 20.III.1993, Prendergast 583 ( K [ K000805559 ]) ; Betioky, May , Réserves Naturelles 3923 ( P [ P03183557 ]) ; 25 km N of Itampolo, 24°13'22"S 43°41'09"E, 25.IV.2014, Vorontsova et al. 1391 ( TAN) ; from delta of the Linta to Ampanihy , 25°02'57"S 44°23'27"E, 25.IV.2014, Vorontsova et al. 1400 ( TAN) ; c. 3 km from Cape Ste Marie towards the ANGAP office, Bevozoa , 25°35'02"S 45°08'32"E, 27.IV.2014, Vorontsova et al. 1418 ( TAN) ; Vavaony beach , 25°36'18"S 45°09'46"E, 28.IV.2014, Vorontsova et al. 1425 ( TAN) ; Ambalanosy, 25°30'22"S 45°06' 57"E, 28.IV.2014, Vorontsova et al. 1438 ( TAN) ; Ambaliandro, 25°21'11"S 45°26'13"E, 29.IV.2014, Vorontsova et al. 1448 ( TAN) . Sine loco: Herb. Stat. Agric. Alaotra 27239 ( P [ P02307348 ], TAN) ; IV.1967, Morat 2937 ( TAN) .

Figures

Fig. 13. – A. Habitat of Panicum spergulifolium A. Camus with P. spergulifolium pink at the forefront; B. Habitat of P. voeltzkowii Mez with the green-brown mat of P. voeltzkowii across the forefront; C. Panicum subhystrix A. Camus; D. Panicum vohitrense A. Camus. [A: Vorontsova et al. 1218; B: Vorontsova et al. 1391; C: Ratovonirina et al. 185; D: Vorontsova & Onjalalaina 1466] [Photos: M.S. Vorontsova]

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).