Gladiolus quadrangularis Ker Gawl.

Plants 350-700 mm high. Corm globose-conic, 12-20 mm diam.; tunics papery to leathery, decaying into fine or medium-textured vertical fibres below. Stem erect, flexed outward above sheaths of two upper leaves, unbranched. Leaves 3, lowermost markedly longest, reaching to between base and apex of spike, sheathing lower part of stem for 50-80 mm, erect or trailing above, centric, 2.5-4.0 mm wide, cross-shaped in section with midrib raised on either side of surface into wing-like ridges, edges of midrib wings and margins lightly thickened, second leaf sheathing stem for ± 2/3 of its length with a short blade, third leaf inserted shortly below spike, sheathing below. Spike erect, nearly straight, 4-to 8(11)-flowered; bracts green, outer 30-45 mm long, inner shorter, forked apically. Flowers scarlet to brick-red, rarely pink, dorsal and lower lateral tepals becoming transparent along lower edges, occasionally lower tepals orange toward bases, unscented; perianth tube (35-)43-55 mm long, lower part slender and cylindric (10-)12-22 mm, abruptly expanded and curved outward into a wider cylindric upper part (15-)24-32 mm long, 5-7 x 4-6 mm wide; tepals lanceolate, dorsal largest, extended horizontally over stamens, (20-)25-29 x (8-)12-15 mm, upper laterals spreading outward almost from base, (16-)20-28 x (6-)9-11 mm, lower tepals curving outward from base, laterals 10-15 x 4.5-6.5 mm, lower median (12-)15-20 x (3-)5-6 mm. Filaments ± horizontal 30-40 mm long, exserted (4-)6-10 mm from tube; anthers 9-11(-14) mm long, yellow; pollen yellow. Style extending horizontally over stamens, dividing between middle and apices of anthers, branches 3.5-4.5 mm long. Capsules ellipsoid, ± 25 mm long. Seeds unknown.