Noronhia macrocarpa, 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 : 166

49. Noronhia macrocarpa Hong-Wa, spec. nova ( Fig. 33B , 34 ).

Typus: MADAGASCAR. Prov. Antsiranana: SAVA, Andapa, Doany, Andranomilolo, versant SE Anjanaharibe, 14°19’43”S 49°18’08”E, 1412 m, 12.XI.2006, Razakamalala et al. 2941 (holo-: MO-6615568!; iso-: G [ G00341627 ]!, K!, P [ P03533806 ]!, TAN) .

Diagnosis

Noronhia macrocarpa Hong-Wa can be distinguished from other congeneric species by its subcoriaceous, lanceolate to obovate leaf blades and its large, rugose fruits, with thick and woody endocarp.

Description

Trees to 20 m tall, trunk to 30 cm diameter; young twigs cylindrical, 0.8-1.9 mm diameter, glabrous; bark brownish, slightly rugose. Leaves opposite, persistent; bud scales deciduous; blades medium green above, lighter below, lanceolate to obovate, 6.5-11 3 2-4 cm, subcoriaceous, glabrous, domatia absent, base acute, margin flat to slightly revolute and undulate, apex acuminate, the acumen 2-10 mm long, midrib slightly sunken above, raised below, secondary veins conspicuous, 8-15 per side, 7.5-18 mm apart, looping 1-4 mm from the margin; petiole medium gray, 8-13 3 1-2.5 mm, partially woody, glabrous. Flowers unseen, but infructescence thyrsoid. Fruiting pedicel 5-10 3 1.8-2.6 mm; young fruits green, blackish when mature, ovoid, 25-28 3 19.5-22.5 mm, surface rugose, apex flat to bluntly pointed; dry pericarp 1.2-2 mm thick; endocarp woody; seed 18.5-19.5 3 9-10 mm.

Etymology

The specific epithet refers to the large fruits of this species.

Distribution, ecology and phenology

Noronhia macrocarpa occurs in low- to high-elevation humid forests on basement rocks in the north, from Anjanaharibe- Sud RS to Nosy Be ( Fig. 27 ). It fruits from September to November.

Conservation status

Noronhia macrocarpa is known only from three collections representing three localities, all of which occur within protected areas (Anjanaharibe Sud, Lokobe, and Tsaratanana-Ambohimirahavavy-Corridor Marojejy). With an EOO of 1,875 km 2, an AOO of 12 km 2, and three subpopulations representing three locations, along with an exclusive known occurrence within protected areas, mostly at high elevations, N. macrocarpa is assigned a preliminary status of “Least Concern”.

Notes

Noronhia macrocarpa most closely resembles N. verrucosa H. Perrier , from which it differs by its partially (vs. entirely) woody petioles, lanceolate (vs. obovate to obtrullate), acuminate (vs. acute to mucronate) leaf blades, and ovoid (vs. subglobose), rugose (vs. areolate to verrucose) fruits. The new species can be recognized by its subcoriaceous, lanceolate to obovate leaf blades and its large fruit, with thick and woody pericarp.

Paratypi

MADAGASCAR. Prov. Antsiranana: Nosy-Be, Lokobe RNI, 13°24’40”S 48°18’50”E, 40-80 m, 24.XI.1994, Antilahimena 195 ( G, K, MO, P, TAN); Andapa, Anjanaharibe-Sud RS, 14°47’S 49°27’E, 1100 m, 13-18.IX.1996, Ravelonarivo et al. 1035 ( G, MO, P, TAN) .

Figures

Fig.33.Photographs of Noronhia Stadtm.ex Thouars

Fig. 34. Noronhia macrocarpa Hong-Wa.

Fig. 27. Distribution maps of species of Noronhia Stadtm. ex Thouars. N. intermedia Hong-Wa to N. macrocarpa Hong-Wa.