Revision of the genus Benthamia A. Rich. (Orchidaceae, Orchidioideae, Habenariinae) Hervouet, Jean-Michel Descourvières, Pascal Hermans, Johan Longou, Ludivine Adansonia 2025 3 2025-07-21 47 11 171 249 LHMV Schltr. Schltr. [969,1300,1688,1715] Liliopsida Orchidaceae Benthamia Plantae Asparagales 55 224 Tracheophyta species monophylla  ( Figs 76; 77)    Repertorium Specierum Novarum Regni Vegetabilis33: 30 ( Schlechter 1924).    TYPE  MATERIAL. —   Madagascar• Haute Matsiatra, massif d’Andringitra; alt.  2200-2600 m;  III.1922;  H. Perrier14387; holotype: P[ P00094540]!;  isotype: P[ P00094541]!.   ETYMOLOGY. — “ Monophylla”, in Greek with a single leaf.   PHENOLOGY. — January to April.   DISTRIBUTION AND ECOLOGY. — Madagascar. A high elevation plant, from 1600 to 2600 m, found in the southern half of the country, mostly from Andringitra massif (Haute Matsiatra region) to Andohahela in the south (Anosy region), in humid mountain grasslands or small patches of vegetation on rocks ( Fig. 78).   CONSERVATION. — This species has a large EOO and is locally abundant, but the AOO is probably less than 2000 km². It was quoted NT by IUCN in 2016 (https://doi.org/10.2305/IUCN. UK.2018-1.RLTS.T44393380A69785668.en).   ADDITIONAL SPECIMENS EXAMINED. —   Madagascar• Analamanga, near Mandraka; 18°55’30”S, 47°56’20”E;  XII.1905;  C. d’Alleizette7066b; L[ L1487725]! •  Haute Matsiatra, pic Boby, Andringitra; 22°11’S, 46°53’E; 1946;  A.M. Homolle1192; P[ P02115319, P02115320]! •  sine loc.; 1946;  A.M. Homolle1263; P[ P00692277]! •  sine loc.; 1946;  A.M. Homolle1277; P[ P00692278]!•  Anosy, massif de l’Andohahela; 24°36’S, 46°42’E; alt.  1800-1975 m;  I.1934;  H. Humbert13608; P[ P0009454, P00094543, P00094544]!,  G!,  TAN! •  Haute Matsiatra, canton Sendrisoa, district Ambalavao; 22°13’S, 46°55’E;  17.I.1958;  C. Rakotovao9938RN; P[ P00692318, P00692461]! •  Haute Matsiatra,  30 kmNW of Fianarantsoa;  VIII.1963;  W.Rauh10613; HEID[ HEID2500341]!•  Haute Matsiatra, pente du Vohidray, Andringitra;  13.I.1971;  J.L. Guillaumet3761; TAN! •  Anosy, massif de l’Andohahela, RN11;  I.1974;  P. Morat4389; P[ P00692454, P00692455]! •  Haute Matsiatra, Andringitra reserve; 22˚10’S, 46˚56’E; alt.  1975 m;  13.I.1987;  M. Nicoll262; K[ K000453691, K000453692]!,  MO[ MO3022623]!,  TAN! •  Haute Matsiatra, Andringitra, near to Pic Boby;  II.2007;  T. Ranariveloet al. 484; K!,  TAN! •  Haute Matsiatra, Andringitra;  D. RobertsDLR119& DLR120; K! •  Haute Matsiatra, Andringitra;  D. Roberts DLR125; K[spirit 76706]!.   NOTES Plants sometimes have two basal leaves (e.g. on Ambondrombe). The flowers have a lip that is very similar to the petals and are reminiscent of some  Holothrixin South Africa. It can form hugecolonies, e.g. on Andringitra. With its elongate spur, this species is not a typical  Benthamiawith a short spur like the typeof the genus,  Benthamia latisatis. Perhaps it belongs to a different genus. The specimen H. Perrier 14387has two sheets in P, but Perrier’s handwriting on specimen P00094540 clearly shows that it is the sheet sent to Berlin for the description by Schlechter, it is therefore the holotype. See also: Schlechter (1930: t.11 n°42), Perrier (1939: 24), Perrier (1939: 30), Cribb & Hermans (2009: 42), Cribb & Hermans (2009: 46), Hervouet (2018: 169).   DESCRIPTION Erect terrestrial herb, 15-50 cmtall. Tubers 2, oblong-fusiform. Stem 1-4 mmin diameter, with 2-3 sheaths at the base and one radical leaf. Leaf 1 (rarely 2), linear to oblong, 6-15 cm× 6-35 mm, a little narrowed towards the base, somewhat acute or shortly acuminate. Rachis 8-15 cmlong, subdense, unilateral, bearing 35-60 flowers. Floral bracts lanceolate-acuminate, 1.5-7 × 0.8-2 mm, normally equalling the flower or sometimes a little longer. Ovary 4.5-6.8 × 0.9-1 mm. Flowers about 3 mmwide, yellow; sepals elliptic-oblong, obtuse, 1-veined, 1.5-3 × 0.8-1.3 mm, lateral sepals navicular, dorsal sepal concave; petals 1.3-3 × 0.9-1.5 mm, as long as the sepals but a little wider and fleshy, oblong, obtuse, 2-veined and a little thickened towards the apex; lip concave, oval-elliptic, 1.8-3.4 × 0.9-1.75 mm, obtuse, entire or obscurely trilobed, the base 3-veined, the anterior part thickened and fleshy; spur narrowly conical, gradually narrowing towards the apex, 1.4-3.5 × 0.4-0.8 mm, somewhat curved. Column 0.5-1.1 × 0.4-0.9 mm, anther subglobose, very obtuse; auricles oblong, subcrenulate, half the length of the anther. 5898708445 1922-03 P H. Perrier Madagascar 2400 massif d'Andringitra Haute Matsiatra 55 224 P00094540 1 holotype 5898708886 [1075,1303,1907,1931] 1922-03 P H. Perrier Madagascar 2400 massif d'Andringitra Haute Matsiatra 55 224 P00094541 1 isotype 5898709117 1905-12 L C. d'Alleizette Madagascar -18.925 Analamanga 21 47.93889 Mandraka 56 225 L1487725 1 5898708755 P A. M. Homolle Andringitra -22.183332 Haute Matsiatra 1261 46.883335 56 225 P02115319, P02115320 1 5898708879 P A. M. Homolle 56 225 P00692277 1 5898708570 P A. M. Homolle 56 225 P00692278 1 5898708795 1934-01 P H. Humbert 1888 -24.6 massif de l'Andohahela 1250 46.7 Anosy 56 225 P0009454, P00094543, P00094544 1 5898708714 [391,421,1792,1816] G 1250 56 225 1 5898708592 [424,476,1792,1816] TAN 1250 56 225 1 5898708980 1958-01-17 P C. Rakotovao Ambalavao -22.216667 Haute Matsiatra 1260 46.916668 Sendrisoa 56 225 P00692318, P00692461 1 5898709021 1963-08 HEID W. Rauh Haute Matsiatra 56 225 HEID2500341 1 Fianarantsoa 5898708764 1971-01-13 TAN J. L. Guillaumet pente du Vohidray Haute Matsiatra 56 225 1 Fianarantsoa 5898708706 1974-01 P P. Morat Anosy 56 225 P00692454, P00692455 1 Fianarantsoa 5898709025 1987-01-13 K, MO, TAN M. Nicoll 1975 Haute Matsiatra Andringitra reserve 56 225 K000453691, K000453692, MO3022623 1 Fianarantsoa 5898708432 [578,775,2003,2027] 1987-01-13 MO M. Nicoll 1975 Haute Matsiatra Andringitra reserve 56 225 MO3022623 1 Fianarantsoa 5898708982 [811,863,1418,1442] 1987-01-13 TAN M. Nicoll 1975 Haute Matsiatra Andringitra reserve 56 225 1 Fianarantsoa 5898708718 2007-02 K T. Ranarivelo Haute Matsiatra Andringitra 56 225 1 Fianarantsoa 5898708934 [1057,1109,1444,1468] TAN 56 225 1 Fianarantsoa 5898709091 K D. Roberts Haute Matsiatra Andringitra 56 225 1 Fianarantsoa 5898708841 K D. Roberts Haute Matsiatra Andringitra 56 225 DLR125 1 Fianarantsoa