Wetschnig, Knirsch & Martínez-Azorín & Pfosser & Wetschnig, 2015

Knirsch, Walter, Martínez-Azorín, Mario, Pfosser, Martin & Wetschnig, Wolfgang, 2015, The reinstatement and rediagnosis of the madagascan genus Rhodocodon (Asparagaceae, Scilloideae), with validation and remarks on H. Perrier’s taxa, Phytotaxa 195 (2), pp. 101-134 : 122

9. Rhodocodon linearifolius Knirsch, Mart. -Azorín & Wetschnig sp. nov.

≡ Rhodocodon calcicola var. linearifolius Perrier de la Bâthie (1938: 116) , nom. inval.

Illustrations:—fig. XVI (11) in Perrier de la Bâthie (1938: 121).

Type:— MADAGASCAR. Rocailles denudées—sur les labradorites de l’Antanimena, December 1924, Perrier 16824 (holotype P 00516239!, Fig. 18 ; isotype P 00516238!) .

Description:—Deciduous bulbous plant, 10 ‒ 15 cm high. Bulb conical, 1.5 ‒ 2.5 × 1 ‒ 1.5 cm, proliferous, bulb scales loosely arranged; roots white, branched. Leaves 5 ‒ 8 per bulb, synanthous but fully developed after the anthesis, very rigid, linear, acute, 3 ‒ 10 × 0.1 ‒ 0.2 cm, green, glabrous, flat or only very slightly canaliculated on the adaxial side, without a distinct keel on the abaxial side. Inflorescence erect; peduncle 3–7 cm long, green, glabrous, smooth; raceme 2 ‒ 9 cm long with 5 ‒ 25 flowers; pedicels 6–10 mm long, suberect to patent; bracts lanceolate, ca. 1.5 mm long, with a spur of ca. 1 mm long; bracteoles absent; flowers white, nodding. Perigone tubular, contracted at the middle, ca. 3 × 1.5 mm, connate for most of their length, the tube being pure white, with six, erect lobes. Stamens 6, converging to the ovary. Capsule obovate to cordate in outline, 2 ‒ 3 × 3 ‒ 4 mm. Seeds hemiellipsoidal, L-H: 3.3 ‒ 2 mm, black, glossy, with a light brown distinct raphe.

Diagnosis:— Rhodocodon linearifolius is easily identified by the rigid, erect, linear narrow leaves and the very proliferous bulbs.

Habitat:— Rhodocodon linearifolius grows in the Plateau d’Antanimena at elevations spanning 130 ‒ 150 m in tropical savanna characterized by winter dry season with highest temperatures in November (mean of 33.7°C), and the lowest temperatures occurring in June (mean 17.1°C). The peak of precipitation is found in January and February and the annual average precipitation is 1486 mm.

Biology:—Flowering and fruiting time: October to December.

Distribution:— Madagascar. Province Mahajanga: Districts Boeny, Betsiboka and Melaky.

Selected material studied:— MADAGASCAR. Pelouses (basaltes) denudées du Plateau d’Antanimena (Boina), October 1901, Perrier 1383 (P 02160885!).

Figures

FIGURE 18. Holotype of Rhodocodon linearifolius Knirsch, Mart.-Azorín & Wetschnig: Perrier 16824 (P 00516239!).