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.

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