Noronhia richardii, Hong-Wa, 2016

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 : 230-232

71. Noronhia richardii Hong-Wa, spec. nova ( Fig. 57).

Typus: MADAGASCAR. Prov. Toliara: Anosy, Fort-Dauphin , Iaboko , Antsotso , forêt Ivohibe , 24°34’26”S 47°11’42”E, 261 m, XII.2005, Razakamalala et al. 2666 (holo-: MO-6615556!; iso-: G [ G00341619 ]!, P [ P06490472 ] image seen, TAN) .

Diagnosis

Noronhia richardii Hong-Wa can be distinguished from other congeneric species by its lanceolate leaves, and its long and diffuse inflorescences with red flowers.

Description

Small trees to 7 m tall; young twigs cylindrical, 0.7-1.4 mm diameter, glabrous; bark medium gray, smooth. Leaves opposite, persistent; bud scales rarely persistent; blades medium green above, yellowish below, lanceolate to oblong, 9-11 3 2-4 cm, chartaceous, glabrous, domatia absent, base acute to rounded, margin slightly revolute, apex acuminate, the acumen 5-9 mm long, midrib flat above, slightly raised below, secondary veins conspicuous, 9-12 per side, 9-17 mm apart, looping 1.3-3 mm from the margin; petiole medium gray, 6-11 3 1-2.5 mm, entirely woody, glabrous. Thyrses geminate, pauciflorous, diffuse; peduncle 4-30 mm long, glabrous; pedicel 11-25 mm long, glabrous; calyx sparsely pubescent to glabrescent outside, glabrous inside, lobes ovate, 1-2.5 3 1-2 mm; corolla red, cupuliform, 3-7 mm long, glabrous on both sides, the tube 1-5 mm long lobes widely ovate, apex acute; corona absent; stamens 2-3 mm long, anthers widely oblong to almost square, 1.6- 1.9 mm long; pistil 2.2-3.5 mm long, stigma capitate. Fruits unseen.

Etymology

This name honors Richard Razakamalala, a botanist at the Missouri Botanical Garden in Madagascar and one of the most knowledgeable Malagasy field botanists, for collecting the type specimen and for providing invaluable preliminary identification on countless field collections.

Distribution, ecology and phenology

Noronhia richardii occurs in low-elevation humid forests on basement rocks at Bemangidy-Ivohibe north of Ste Luce in the south ( Fig. 49 ). It has been collected in flowers in November and December.

Conservation status

Only three collections, representing three localities, were available and were all obtained from a single location within the recently established protected area of Tsitongambarika. The subpopulation occurs on the northeastern edge of the protected area, where significant human activities still put some pressure on the forest, resulting in continuing decline in habitat quality. Thus, with an AOO of just 8 km 2, a single location, and lingering threats that could rapidly affect the area, N. richardii is assigned a preliminary status of “Vulnerable” [VU D2].

232 Boissiera 70

Notes

Noronhia richardii closely resembles N. capuronii , from which it differs by its glabrous (vs. pubescent) petioles, lanceolate to oblong (vs. ovate) leaf blades with an acute to rounded (vs. cordate) base, long peduncles and pedicels (up to 30 mm vs. 8 mm), and red (vs. greenish) flowers. It can be recognized by its lanceolate leaves and long, diffuse inflorescences with red flowers.

Paratypi

MADAGASCAR. Prov. Toliara: Fort-Dauphin, Iaboko, Antsotso , forêt d’Ivohibe, 24°34’14”S 47°12’04”E, 265 m, 28.XI.2005, Razakamalala et al. 2424 ( G, MO, P, TAN); ibid. loc., 24°34’16”S 47°12’06”E, 271 m, 8.XII.2007, Razakamalala et al. 3777 ( MO, P, TAN) .

Figures

Fig. 49. Distribution maps of species of Noronhia Stadtm.ex Thouars. N. pervilleana (KnobL.) H. Perrier to N. seyrigii H. Perrier.