Plants cespitose, to 110 cm. Roots basal, 1.5-4 mm diam. Stems unbranched, straight, compressed, to 60 cm. Leaves 5-13; petiole 20-36 mm; blade elliptic, obtuse, middle ones somewhat larger than basal or apical, 4-18 × 1-4 cm, leathery. Inflorescences racemes, subcapitate, densely flowered, 10-50 cm; 1st raceme terminal, producing additional racemes from nodes of long peduncle over years; peduncle elongate, laterally compressed, 9-48 cm. Flowers to 25 per raceme, not resupinate, spirally oriented, yellow-green to red-brown; sepals obovate-elliptic, 5.5-7.5 × 3-4 mm, fleshy, apex obtuse; petals narrowly oblanceolate, thin, 5-7 × 0.5-1 mm, apex obtuse; lip cordate, apex 2-lobed, 4-6 × 4.5-7 mm, fleshy, with prominent longitudinal ridge terminating in fleshy mucro; column 5 mm; anther ovoid, apex saddle-shaped; ovary 7-14 mm. Capsules subglobose; pedicel 6.5 mm; body 7.5 × 6 mm; beak obsolete.

Flowering Dec--Jul. Widespread and common in forests and hammocks of the Big Cypress Swamp and Everglades, on deciduous trees and palms; 0--30 m; Fla.; West Indies (Cuba).

Epidendrum amphistomum grows in Martin, Lee, Collier, Miami-Dade, and Monroe counties, Florida.

The species is pollinated by male night moths: Eucereon carolina, Lymire edwardsii, Cisseps fulvicollis, and Oxydia vesulia. Its reproduction is obligately allogamous. Flowers produce a fragrance reminiscent of overly ripe vegetables, heaviest between late afternoon and dawn (R. M. Adams and G. J. Goss 1976).

This name has been generally regarded as synonymous with Epidendrum anceps Jacquin, which L. A. Garay and H. R. Sweet (1974) considered synonymous with Epidendrum secundum Jacquin (E. Hágsater 1993).

Outside the flora area are several closely related species, all of them having been considered by recent authors under the name Epidendrum anceps.