Noronhia randrianaivoi, 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 : 220

68. Noronhia randrianaivoi Hong-Wa, spec. nova ( Fig. 52 , 53).

Typus: MADAGASCAR. Prov. Toliara: Anosy, Fort-Dauphin, Ankarara , Tsimelahy , à 6 km à l’E du gite (bureau de l’ANGAP), 24°56’37’’S 46°39’10’’E, 227 m, 4.III.2008, Randrianaivo et al. 1564 (holo-: MO-6615567!; iso-: G [ G00341626 ]!, P, TAN) .

Diagnosis

Noronhia randrianaivoi Hong-Wa can be distinguished from other congeneric species by its short, non-woody petioles, its ovate leaves, its long, diffuse inflorescences, with cupuliform, red flowers.

Description

Shrubs; young twigs cylindrical, 0.7-0.8 mm diameter, glabrous; bark medium gray, smooth. Leaves opposite, persistent; bud scales deciduous; blades dark green above, lighter below, ovate, 4-6.5 3 2-3 cm, coriaceous, glabrous, domatia absent, base cordate, margin slightly revolute, apex acuminate, the acumen 3-4 mm long, midrib flat above, slightly raised below, secondary veins conspicuous mostly above, 6-8 per side, 5-10 mm apart, looping 2-3 mm from the margin; petiole green, 2 3 1-1.6 mm, not woody, glabrous. Thyrses solitary, pauciflorous, diffuse; peduncle 11-21 mm long, glabrous; pedicel 8-11 mm long, glabrous; calyx sparsely pubescent outside, glabrous inside, lobes triangular, 1-1.5 3 1-1.3 mm; corolla red, cupuliform, 5-7 mm long, glabrous on both sides, the tube 2-3 mm long, widely ovate, apex acute; corona present, 1.5 mm long, lobed; stamens 2 mm long, anthers widely oblong, 1.5 mm long; pistil 2.8 mm long, stigma capitate to bilobed. Fruits unseen.

Etymology

This name honors Richard Randrianaivo, a botanist at the Missouri Botanical Garden in Madagascar, for collecting the type specimen and for contributing to the knowledge of the Malagasy flora.

Distribution, ecology and phenology

Noronhia randrianaivoi occurs in mid-elevation transitional forests and basement rocks in Andohahela PN in southern Madagascar ( Fig. 49 ). It has been collected in flowers in March.

Conservation status

Noronhia randrianaivoi is currently known only from a single collection made outside a protected area, where decline in habitat quality resulting from forest exploitation continues. With an AOO of just 4 km 2, a single location and projected continuing decline, N. randrianaivoi is assigned a preliminary status of “Critically Endangered” [CR B2(iii)].

Notes

Noronhia randrianaivoi is similar to N. ovalifolia , but can be distinguished by its nonwoody (vs. woody) petioles, thyrsoid inflorescences (vs. solitary flowers), and red (vs. pink) corolla. Distinguishing features of this species include short, non-woody petioles, ovate leaf blades, long, diffuse inflorescences, and cupuliform, red flowers.

Figures

Fig. 52. Noronhia randrianaivoi Hong-Wa.

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