Hannonia is a genus of plants in the Amaryllis family.[1] It contains only one known species, Hannonia hesperidum, endemic to Morocco and confined to Western Morocco, Promontory of Hercules.[2] [3] [4] The specific epithet comes from Greek έσπερος, of evening, as the flowers open in the late afternoon.
The bulbs are 20-25x20 mm., with brown papery tunics; they have a long neck about 4 cm long. The species is hysteranthous. Scape about 10 cm high, 2-edged, a little twisted, hollow (according to; solid according to [5]), terete; umbel two-flowered. Outermost leaf reduced to a scarious sheath with a very short blade, inner leaves 2 or 3, linear, fleshy, glaucous, flat, just 2 mm wide and 20 cm long. Spathe bracts two, free, but appressed to the scape below their middle. The pedicel is 1 cm, green; the perianth has a short green tube, 5 mm, much shorter than the tepal segments, spreading in six white tepals, 15 mm long and 2.5 mm wide, linear-lanceolate, a bit broadened below the apex, gradually attenuate (narrowing) towards the base, subequal (nearly equal), keeled green on the abaxial surface, keel formed by 3 closely spaced veins. The stamens are biseriate, free, inserted at the throat, 3 equaling the tepals, 3 shorter; filaments filiform; anthers dorsifixed (attached to the filaments at their middle), oblong, versatile, yellow; style white, filiform, and terete. Stigma captitate, obscurely 3-lobed. Ovary with 3 locules; ovules 5-6 per locule.
Flowering period: late summer. Each flower lasts just one day. No scent. Grows in rock-fissures, a very sandy-gritty soil is needed in cultivation. No water in summer and very little in winter. In areas which experience frost a frost-free bulb frame or a greenhouse have to be used. Full sun.
This genus was placed in tribe Galantheae by Traub on the basis of morphology only; molecular investigations are inconclusive.
The name Hannonia hesperidum var. legionariorum was coined in 1935[6] for a Moroccan plant initially thought to be a variety of Hannonia hesperidum. The name is, however, now considered a synonym of Vagaria ollivieri in the genus Vagaria.[2] [7] [8]