Noronhia peracuminata H. Perrier

Hong-Wa, Cynthia, 2016, A taxonomic revision of the genus Noronhia Stadtm. ex Thouars (Oleaceae) in Madagascar and the Comoro Islands, Boissiera 70, pp. 1-292 : 206

63. Noronhia peracuminata H. Perrier in Mém. Inst. Sci. Madagascar, Sér. B, Biol. Vég. 2: 299. 1949.

Typus: M ADAGASCAR. Prov. Antsiranana: base des montagnes bordant la vallée du Sambirano, [14°19’00’’S 48°17’30’’E], VIII.1907, Perrier de la Bâthie 8823 (holo-: P [ P00418094 ]!; iso-: P [ P00418093 ]!) .

Description

Trees to 9 m tall, trunk to 15 cm diameter; young twigs cylindrical, 0.6-0.8 mm diameter, glabrous; bark medium gray, smooth. Leaves opposite, persistent; bud scales persistent; blades medium green, lighter below, lanceolate, 6.5-7.5 3 2 cm, chartaceous, glabrous, domatia absent, base acute to attenuate, margin slightly undulate, apex acuminate, the acumen 14-19 mm long, midrib slightly sunken above, flat to raised below, secondary veins conspicuous, 7-8 per side, 8-9.5 mm apart, looping 1.5-2.2 mm from the margin; petiole light gray to brownish, 4-6 3 0.7-0.8 mm, partially to entirely woody, glabrous. Flowers geminate, sometimes solitary; pedicel 5-12 mm long, glabrous; calyx glabrous on both sides, lobes triangular, 1-1.5 3 1 mm; corolla red tinged yellowish, cupuliform, 5 mm long, glabrous on both sides, the tube 3.5 mm long, lobes ovate, apex acute; corona present, 2 mm long, undivided; stamens 2 mm long, anthers obovate, 1.6 mm long; pistil 2.2 mm long, stigma capitate. Fruiting pedicel 13-20 0.8-1.2 mm; young fruits green, brownish when mature, ovoid, 18 3 8 mm, surface smooth, apex apiculate to rostrate, the rostrum flattened, apiculate; dry pericarp 0.3 mm thick; endocarp crustaceous; seed 8 3 5 mm.

Distribution, ecology and phenology

Noronhia peracuminata occurs in low- to mid-elevation riparian and rupicolous vegetation on sandstones in the Sambirano region in northwestern Madagascar ( Fig. 36 ). It has been collected in flowers and fruits in August and November.

Conservation status

Noronhia peracuminata is currently known only from two collections representing two localities. With an AOO of 8 km 2, two subpopulations representing two locations, of which one occurs within a protected area (Manongarivo), and a projected continuing decline in habitat quality and number of mature individuals as well as habitat loss resulting from forest exploitation and land conversion, N. peracuminata is assigned a preliminary status of “Endangered” [EN B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v)].

Notes

Noronhia peracuminata can be recognized by its chartaceous leaf blades with a long acumen, geminate, sometimes solitary, red flowers, and apiculate, crustaceous fruits. It differs from N. rostrata by its woody (vs. non-woody) petioles, red (vs. white) flowers, and apiculate (vs. rostrate) fruits.

Additional specimens examined

MADAGASCAR. Prov. Antsiranana: Ambahatra (cours moyen), Manongarivo RS, 13°55’43”S 48°27’19”E, 230 m, 19.XI.2000, Wohlhauser 327 ( G, MO, P) .

Figures

Fig. 36. Distribution maps of species of Noronhia Stadtm. ex Thouars.N. maculata Hong-Wa to N. perrieriana Hong-Wa.