Benthamia glaberrima (Ridl.) H.Perrier

Hervouet, Jean-Michel, Descourvières, Pascal, Hermans, Johan & Longou, Ludivine, 2025, Revision of the genus Benthamia A. Rich. (Orchidaceae, Orchidioideae, Habenariinae), Adansonia (3) 47 (11), pp. 171-249 : 204-205

Benthamia glaberrima (Ridl.) H.Perrier

( Fig. 45 )

Bulletin de la Société botanique de France 81 ( Perrier 1934: 28). — Holothrix glaberrima Ridl. , Journal of the Linnean Society, Botany, vol. 22: 125 ( Ridley 1886); Perrier (1939: 22). — Peristylus glaberrima (Ridl.) Rolfe , Orchid Review 7 (73): 4 ( Rolfe 1899). — Platanthera glaberrima (Ridl.) Kraenzl. , Orchidacearum Genera et Species, vol. 1: 609 ( Kraenzlin 1899). — Habenaria glaberrima (Ridl.) Schltr., Beihefte zum Botanischen Centralblatt 33: 405 ( Schlechter 1915). — Rolfeella glaberrima (Ridl.) Schltr., Repertorium Specierum Novarum Regni Vegetabilis 33: 18 ( Schlechter 1924).

Habenaria deceptrix Baron ex Ridley , nomen nudum in Baron’s “ Compendium des plantes Malgaches ”. Revue de Madagascar, vol. 3, no. 10: 722 ( Baron 1901).

TYPE MATERIAL. — Madagascar • Analamanga, Ambatovory; 18°54’S, 47°42’E; III.1882; J. T. Fox 23; holotype: K [ K000415546 ] !.

ETYMOLOGY. — From Latin “ glaber ”, glabrous, with superlative ending “ rima ” thus completely smooth, without hairs.

PHENOLOGY. — January to May.

DISTRIBUTION AND ECOLOGY. —Restricted to the central mountains and plateaux of Madagascar, from 1500 to 2250 m, in dry montane grasslands, also rocky outcrops and sometimes humid places ( Fig. 46 ). CONSERVATION. — Widespread in Madagascar, this species is considered of Least Concern (LC). However, it was considered Near Threatened (NT) by IUCN in 2015 (https://doi.org/10.2305/ IUCN. UK.2015-2.RLTS.T68002690A68015027.en).

ADDITIONAL SPECIMENS EXAMINED. — Madagascar • Imerina; R. Baron 849; BM ! • sine loc.; Deans Cowan 23; BM!, B!, M000032247 ! • sine loc.; B. Pettersson et al. 221; K! flowers in spirit [K55124.000] • Montagnes d’Amoron Kay, est de l’Imerina; alt. 1600-1900 m; H. Rusillon 166; G ! • Ambatovory; III.1886; J. T. Fox 23; K! ex LDS • north west, IX.1887; R. Baron 5240; K! mounted with G. F. Scott Elliot 1944 and Baron 849 • Near Mahabo; 19°07’S, 46°58’E; received IV.1890; G. F. Scott Elliot 1944; K ! • Vakinankaratra, cime du Famoizankova près d’Antsirabe; 19°39’32”S, 47°03’48”E; alt. 2200 m; V.1912; H. Perrier 11385; P [ P00094511 ] ! • Vakinankaratra, pente du mont Ibity au sud d’Antsirabe; alt. 1800-2200 m; 20°05’44”S, 47°00’12”E; II.1914; H. Perrier 8087; P [ P00094510 the plant on the right is Benthamia rostrata ] ! • Haute Matsiatra, massif d’Andringitra; alt. 2000 m; I.1922; H. Perrier 14326; P [ P00094512 ] ! • Vakinankaratra, flanc Est du Tsiafajavona; 19°19’58”S, 47°16’08”E; alt. 2000 m; 1928; H. Perrier 13518; P [ P00094508 , P00094509 ] ! • Analamanga, massif de l’Angavo près d’Ankazobe; 18°14’S, 47°02’E; 10.III.1930; R. Decary 7325; P [ P00094505 ] ! • Analamanga, Tampoketsa au nord d’Ankazobe; 18°12’56”S, 47°17’17”E; 12.III.1930; R. Decary 7453; P [ P00094504 ]!, TAN • Analamanga, massif de l’Angavo près d’Ankazobe; 18°14’S, 47°02’E; 16.III.1930; R. Decary 7600; P [ P00094506 ] ! • Amoron’i Mania, montagnes à l’ouest d’Itremo; 20°34’12”S, 46°34’55”E; alt. 1500-1700 m; 1955; H. Humbert 30055; P [ P00692284 all but second specimen]!, P [ P00692285 specimen on the right only]!, P [ P00692286 ]!, TAN ! • Vakinankaratra, environs de Faratsiho (face ouest de l’Ankaratra); 19°24’S, 46°57’E; alt. 1800 m; II.1957; J. Bosser 10864; P [ P00094507 ]!, TAN ! • Analamanga, Iarinandriana, 40 km from Antananarivo; 19°10’S, 47°30’E; IV.1957; J. Bosser 11061; TAN ! • Vakinankaratra, massif de l’Ibity; 20°10’S, 47°01’E; 19.III.1960; M. Peltier 2112; P [ P00692291 ] ! • Amoron’i Mania, Ambositra, Anjoma; III.1960; J. & M. Peltier 2173; TAN! plant on the right • Amoron’i Mania, route Ambositra à Ambatofinandrahana; 20°40’03”S, 47°08’03”E; III.1960; M. Keraudren 148; P [ P00692288 , plant in the middle only] ! • Haute Matsiatra, route Ambositra à Ambatofiterahana à 99 km de l’embranchement d’Ivato; 20°40’03”S, 47°08’03”E; III.1960; M. Keraudren 157; P [ P00692289 ] ! • Vakinankaratra, col des Tapias, 45 km avant Ambositra; 20°14’34”S, 47°06’04”E; IV.1964; J. Bosser 19597; P [ P00692258 ] ! • Haute Matsiatra, Andringitra Forest Reserve , along path to Pic Boby; 22°11’S, 46°55’E; alt. 1900-2050 m; 23.III.1989; P. Goldblatt et al. 8965; K!, MO [ MO3011473 ] ! • Vakinankaratra, Ankaratra Massif W of Ambatolampy ; 19°20’S, 47°16’E; III.1989; P. Goldblatt et al. 9011; K!, MO [ MO4314444 ] ! • Analamanga, c. 85 km in direction Ankazobe; 18°15’59”S, 47°10’53”E;. XII.1998; W. Rauh R21598 ; HEID [ HEID744389 ] ! • Vakinankaratra, Ibity, Mt. Kiboy ; 20°05’44”S, 47°00’12”E; alt. 1600 m; 1999; J. Hermans 2410; K ! • Haute Matsiatra, Ambondrombe; alt. 2000 m; 1999; J. Hermans 4406; K ! • Amoron’i Mania, Ambatofinandrahana, W of Itremo ; 20°34’12”S, 46°34’55”E; 2002; J.Hermans 3382; K !• Vakinanakaratra, Ibity Massif; 20°04’10”S, 47°00’16”E; alt. 1700 m; II.2003; G. E. Schatz et al. 4097; TAN!, MO ! • Vakinanakaratra, Ibity Massif; alt. 1700 m; 17.II.2003; G. E. Schatz et al. 4139; MO [ MO3022642 ] ! • Haute Matsiatra, Andringitra; alt. 1987 m; I.2005; G. Fischer et al. FS2031-2005; WU0848511 ! • Vakinankaratra, Mt. Ibity , Ankobohy; 20°04’30”S, 47°00’47”E; II.2007; T. Ranarivelo et al. 465; TAN!, K ! • Amoron’i Mania, Ambatofinandrahana, Itremo massif, about 25 km from Itremo village ; 20°33’42”S, 46°33’49”E; alt. 1647 m; II.2010; L. R. Rajaovelona et al. RJL145; K!, TAN ! • Haute Matsiatra, RN 7 PK420.7, bifurcation à droite vers la commune d’Andoharanomaitso; 21°30’07”S, 46°58’43”E; alt. 1293 m; 14.III.2010; L. Ramandimbisoa et al. 58; P [ P06773266 ] !.

NOTES

The species can be easily recognised in herbaria by its basal leaves followed by a series of prominent long acuminate sheaths, then by its dense rachis and also by its long and filiform spur. See also: Cribb & Hermans (2009: 40), Bosser & Lecoufle (2011: 176), Hervouet (2018: 164).

DESCRIPTION

Erect terrestrial herb, 30-60 cm tall. Tubers 4-5, bunched, oblong-fusiform; Stem 2-3 mm in diameter, with a single radical sheathing leaf, higher covered by 6-11 acuminate sheaths 20-35 mm long. Leaf narrowly lanceolate-acute, 8.5- 16 × 0.9-1.4 cm, very gradually narrowed towards the base, 5-veined. Rachis very dense, with 20-55 flowers, unilateral, 5-19 cm long. Floral bracts lanceolate, longly acuminate, 10-20 × 2.5-5 mm, normally longer than the flower. Ovary twisted, 5.5-10 × 1-2.5 mm. Flowers small, sulphur yellow; all sepals narrowly ligulate, a little fused to the petals at the base, dorsal sepal 5.1-7.5 × 0.6-1.3 mm, lateral sepals 4.5-8 × 0.5-1.8 mm; petals lanceolate, 5.2-8 × 0.6-2.1 mm, slightly longer than the sepals; lip oval in outline, 5.2-7.5 × 3-4.5 mm, obviously trilobed, a little fused with the sepals at the extreme base; midlobe oval-acute, the lateral lobes much smaller; spur filiform, pendent, 7.2-10 × 0.5-1.2 mm, a little longer than the ovary. Column straight, 1.1-2 × 0.9-1.5 mm; anther obtuse or subapiculate; auricles small, rounded, pollinia claviform with a very short caudicula; rostellum small, tridentate.

Figures

FIG. 45. — Benthamia glaberrima (Ridl.) H.Perrier: Mount Ibity, Madagascar, 5 March 2009. Photograph by Jean-Michel Hervouet.

FIG. 46. — Distribution map of Benthamia glaberrima (Ridl.) H.Perrier.