Noronhia verrucosa 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 : 275-276

86. Noronhia verrucosa H. Perrier in Mém. Inst. Sci. Madagascar, Sér. B, Biol. Vég. 2: 283. 1949.

Typus: M ADAGASCAR. Prov. Toamasina : N d’Andilamena, [17°01’S 48°35’E], 900 m, XI.1922, Perrier de la Bâthie 15026 (holo-: P [ P00418104 ]!) .

Description

Trees to 8 m tall, trunk to 18 cm diameter; young twigs cylindrical to subquadrangular, 1.6-2.2 mm diameter, glabrous; bark medium gray to brownish, smooth to slightly rugose. Leaves opposite, verticillate at the tips of the branches, persistent; bud scales persistent; blades dark green above, lighter below, obovate to obtrullate, sometimes oblong, 5.5-9.5 3 2-4 cm, coriaceous, glabrous, domatia common, base acute to attenuate, margin flat to slightly undulate, apex acute to mucronate, the mucro 2-6 mm long, midrib sunken above, raised below, secondary veins conspicuous, 8-12 per side, 5-12 mm apart, looping 1.5-4 mm from the margin; petiole medium gray, 5-11 3 2-2.5 mm, entirely woody, glabrous. Thyrses geminate, pauciflorous, compact; peduncle 6-12 mm long, moderately pubescent; pedicel 4-7 mm long, moderately pubescent; calyx moderately pubescent outside, glabrous inside, lobes triangular, 1.5-1.8 3 0.5-1.3 mm; corolla probably white to yellow, cupuliform, 3-4 mm long, glabrous on both sides, the tube 1.5-2 mm long, lobes oblong, apex rounded; corona present, 1.5-2 mm long, undivided; stamens 1.8-2.1 mm long, anthers oblong, 1.1-1.5 mm long; pistil 1.5-2.3 mm long, stigma capitate. Fruiting pedicel 5-16 3 1.7-2.2 mm; young fruits whitish green, yellowish when mature, subglobose, 17.5-19 3 14.5-15.5 mm, areolate to verrucose, apex flat; dry pericarp 1.8 mm thick; endocarp woody; seed 11 3 7 mm.

Distribution, ecology and phenology

Noronhia verrucosa occurs in low- to mid-elevation humid forests on basement rocks in the east, between Mandritsara, Andilamena and Betampona ( Fig. 68 ). It produces flowers and fruits from November to April.

Conservation status

Based on six collections representing six localities, the assessment yielded an EOO of 14,382 km 2, an AOO of 24 km 2, and six subpopulations representing six locations, of which three occur within protected areas (Betampona, Mananara-Nord, and Zahamena). The forests outside of these protected areas still experience much disturbance, resulting in continuing decline in habitat quality, AOO and number of mature individuals. These disturbances are mostly in the form of wood harvesting and shifting agriculture. Noronhia verrucosa is, therefore, assigned a preliminary status of “Vulnerable” [VU B1ab(ii,iii,v)+2ab(ii,iii,v)].

Notes

Noronhia verrucosa can be recognized by its obovate to obtrullate leaf blades that are verticillate at the tips of the branches, its compact inflorescences, and its areolate to verrucose fruits. It differs from N. macrocarpa , as previously discussed, by the texture of its petioles, the shape of its leaves and fruits, and the surface of its fruits.

276 Boissiera 70

Additional specimens examined

MADAGASCAR. Prov. Mahajanga: Mandritsara, Marotandrano , Antsiatsiaka , Ambendraria , 16°03’34”S 49°06’45”E, 764 m, 9.XI.2004, Lehavana 200 ( G, MO, P, TAN); Mandritsara, Antsirabe , forêt d’Angijombarika, [15°57’30”S 48°58’00”E], 1100 m, 17.VIII.1954, Service Forestier 10605 ( P, TEF) . Prov. Toamasina: Betampona RNI, 17°55’S 49°13’E, 15.IV.1999, Iambana 201 ( G, MO, P); Manambato forest , N of riv. Anove between Mananara and Manompana, 16°32’S 49°43’E, 125 m, 25.II.1987, Nicoll 510 ( MO, TAN); Zahamena RNI, Mt d’Amboditamenaka , 17°43’S 48°59’E, 700 m, 20.XII.1993, Randrianjanaka & Be Maxime 46 ( MO, TAN) .

Figures

Fig. 68. Distribution maps of species of Noronhia Stadtm. ex Thouars.N. urceolata H. Perrier to Noronhia verticillata H. Perrier.