42. Noronhia leandriana H. Perrier in Mém. Inst. Sci. Madagascar, Sér. B, Biol. Vég. 2: 289. 1949.

Typus: M ADAGASCAR. Prov. Mahajanga: Ouest, Tsingy du Bemaraha (9e Réserve Naturelle), secteur du Menabe, [18°12’S 44°35’E], 1932-1933, Leandri 1004 (holo-: P [P00413235]!; iso-: K [K000233188] image seen, P [P00413236, P00701476]!) .

Description

Trees to 20 m tall, trunk to 35 cm diameter; young twigs cylindrical, 0.6-2.6 mm diameter, glabrous; bark dark to medium gray, smooth. Leaves opposite, persistent; bud scales persistent; blades light green, oblong, 9-20 3 2-5 cm, chartaceous, glabrous, domatia common, base attenuate, margin flat to slightly undulate, apex acute to acuminate, the acumen 1-15 mm long, midrib sunken above, raised below, secondary veins conspicuous, 7-17 per side, 7-19 mm apart, looping 1-4 mm from the margin; petiole yellow to orangish, 5-15 3 0.7-2.2 mm, not woody, glabrous. Thyrses geminate to fasciculate, multiflorous, diffuse; peduncle 2-25 mm long, moderately pubescent; pedicel 2.5-13 mm long, moderately pubescent; calyx moderately pubescent outside, glabrous inside, lobes triangular, 0.9-1.4 3 1.2-1.8 mm; corolla yellowish-green, rotate, 3-4.5 mm long, glabrous on both sides, the tube 0.5-2 mm long, lobes ovate, apex acute; corona present, 1.2-2 mm long, slightly lobed; stamens 1.4-2.1 mm long, anthers widely oblong, 0.9-1.3 mm long; pistil 1.5-2 mm long, stigma capitate. Fruiting pedicel 5-18 3 0.6-1.7 mm; young fruits green, brownish when mature, ovoid, 13-26 3 9.5-16 mm, surface slightly rugose, apex bluntly pointed to rostellate, the rostellum flattened, ridged, truncate; dry pericarp 0.6-1 mm thick; endocarp woody; seed 9-20 3 7.5-11 mm.

Distribution, ecology and phenology

Noronhia leandriana occurs in low- to mid-elevation dry forests on limestones and basement rocks in the west, from Sofia to Antsalova (Fig. 27). It produces flowers and fruits throughout the year except in September and October.

Conservation status

Based on seven collections representing six localities, the assessment indicated an EOO of 13,337 km 2, an AOO of 24 km 2, and six subpopulations representing six locations, of which three occur within protected areas (Bemaraha and Corridor Bongolava). Continuing decline in habitat quality, AOO and number of mature individuals are expected outside these protected areas due to fire, wood harvesting, forest exploitation, land conversion and artisanal mining. Therefore, N. leandriana is assigned a preliminary status of “Vulnerable” [VU B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v)].

Notes

Noronhia leandriana can be recognized by its chartaceous, oblong leaf blades and large inflorescences with rotate flowers. It differs from N. urceolata H. Perrier by its nonwoody (vs. woody) petioles, rotate (vs. urceolate) flowers, the presence (vs. absence) of a corona, and its woody (vs. crustaceous) endocarp.

Additional specimens examined

MADAGASCAR. Prov. Mahajanga: Bekopaka, Antsalova, [19°08’S 44°47’E], 4.VII.1970, Jacquemin 754 (P) ; Antsingy, vers Bevary (E d’Antsalova), [18°37’S 44°48’E], 400-600 m, 27.I-5. II.1960, Leandri & Saboureau 2847 (G, MO, P) ; Bords de la Mahavavy, au-dessus de Itampika (Ambongo), [16°23’S 45°53’E], IX.1904, Perrier de la Bâthie 1757 (P) ; Causse d’Ankara (Boina), [17°13’S 46°16’E], VIII.1922, Perrier de la Bâthie 14827 (P) ; Melaky, Antsalova, [18°27’S 44°44’E], 25. II.1960, Réserves Naturelles 11116 (P, TEF) ; Ambondrona, Maevatanana, [16°57’S 46°50’E], 16. V.1955, Service Forestier 14938 (MO, P, TEF) ; Ambodiriana II, Port-Bergé, [15°55’S 47°29’E], 0-300 m, 24.XI.1958, Service Forestier 19236 (MO, P) ; 14 km E Antsalova, [18°30’S 44°45’E], 18.III.1993, Villiers et al. 4830 (P) .