Habenaria

Willdenow

Sp. Pl. 4(1): 5, 44. 1805.

Common names: Rein orchid
Etymology: Latin habena, rein or strap
Treatment appears in FNA Volume 26. Treatment on page 581. Mentioned on page 497, 570.
Revision as of 16:41, 18 September 2019 by FNA>Volume Importer

Herbs perennial, terrestrial or semiaquatic, often rather succulent. Roots scattered along basal portion of stem, both slender and tuberous, fleshy; tuberoids usually spheroid. Stems: leaves basal, abruptly reduced to bracts or scattered, gradually reduced toward inflorescence. Leaves several, alternate, ascending to spreading, conduplicate, bases sheathing stem. Inflorescences terminal, lax to rather dense spicate racemes; bracts large and foliaceous to reduced. Flowers few to many, resupinate, pedicellate, sometimes showy; petals 2-lobed, lateral lobe on abaxial margin; lip 3-lobed, spurred at base; pollinaria 2; pollinia 2; viscidia free; stigma with 2 fleshy processes flanking or encircling mouth of spur. Fruits capsules, ellipsoid.

Discussion

Species ca. 600 (4 in the flora).

A recently identified species, Habenaria macroceratitis, is described but not fully treated here.

Key

1 Lateral lobes of lip and petals greatly reduced; lip hastate-auriculate; petals auriculate on abaxial margin. Habenaria odontopetala
1 Lateral lobes of lip and petals prominently filiform, nearly equal to or exceeding other lobes; lip conspicuously 3-lobed; petals conspicuously 2-lobed. > 2
2 Spur more than 4 cm (often much more). Habenaria quinqueseta
2 Spur at most 2 cm (often much shorter). > 3
3 Leaves basal, spreading, broadly elliptic to ovate or obovate; spur slenderly clavate. Habenaria distans
3 Leaves scattered along length of stem, ascending, linear-lanceolate to lanceolate, narrowly elliptic, or oblanceolate; spur slenderly cylindric to scarcely clavate. Habenaria repens