Noronhia cuspidata

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 : 85-87

20. Noronhia cuspidata Hong-Wa, spec. nova ( Fig. 12C , 13 ).

Typus: M ADAGASCAR. Prov. Toamasina: Alaotra-Mangoro, Zahamena PN, Antanandava, sur la piste entre Ankosy et Antenina, 17°29’03”S 48°44’48”E, 900 m, 13.VII.2000, Rakotondrajaona et al. 126 (holo-: MO-6615563!; iso-: CNARP, G [ G00341624 ]!, K, P [ P03559027 ]!, TEF) .

Diagnosis

Noronhia cuspidata Hong-Wa can be distinguished from other species of this genus by the presence of domatia on its stems, its reddish petioles, its broadly elliptic leaf blades terminated by a short cusp and its subcrustaceous, ovoid fruits.

Description

Trees to 16 m tall, trunk to 20 cm diameter; young twigs cylindrical, 1-2 mm diameter, glabrous; bark medium gray, smooth. Leaves opposite, persistent; bud scales deciduous; blades medium green above, lighter below, broadly elliptic, 6-11 3 3-5 cm, subcoriaceous, glabrous, domatia casual, present also on stems, base attenuate, margin flat, apex cuspidate, the cusp 7-14 mm long, midrib slightly sunken above, distinctly raised below, secondary veins conspicuous, 8-12 per side, 6-16 mm apart, looping 2-4 mm from the margin; petiole red, 5-9 3 1-2.7 mm, rarely woody, glabrous. Flowers unseen, but infructescence thyrsoid. Fruiting pedicel 3-12 3 1.2-2.7 mm; young fruits green, purplish green when mature, ovoid, 17.5-23 3 14.5-19 mm, surface smooth, apex bluntly pointed; dry pericarp 0.6-1 mm thick; endocarp subcrustaceous; seed 12.5-16 3 7-14.5 mm.

Etymology

A cuspidate leaf blade is one of the prominent features of this species, from which its name was derived.

Distribution, ecology and phenology

Noronhia cuspidata occurs in low- to high-elevation humid forests on basement rocks in the east, from Mangoro to Zahamena ( Fig. 9 ). It fruits from July to October.

Conservation status

Noronhia cuspidata is currently known only from three collections representing three localities. With an EOO of 6,658 km 2, an AOO of 12 km 2, and three subpopulations representing three locations, all of which occur within protected areas (Analamazaotra, Masoala, and Zahamena) where rapid continuing decline is not expected in the near future, N. cuspidata is assigned a preliminary status of “Least Concern”.

Notes

Noronhia cuspidata is similar to N. decaryana H. Perrier , but can be distinguished by its broadly elliptic (vs. oblong to elliptic) leaf blades, often covered with domatia (vs. rarely so) on the lower surface, and its subcrustaceous (vs. crustaceous) endo-carp. Distinctive features of this new species include the presence of domatia on its stems, as well as its reddish petioles, broadly elliptic leaf blades terminated by a short cusp, and subcrustaceous, ovoid fruits.

86 Boissiera 70

Paratypi

MADAGASCAR. Prov. Toamasina: Andasibe, Analamazaotra RS, 18°56’12”S 48°25’09”E, 953 m, 2. V .2010, Hong-Wa & Ortiz 643 ( MO, P, TAN); Ambatondradama (env. 10 km au NE d’Ankovona), Navana, 15°17’08”S, 50°01’14”E, 400 m, 1-6.X.1997, Ralimanana et al. 123 ( G, K, MO, P, TAN) .

Figures

Fig. 12. Photographs of Noronhia Stadtm.ex Thouars.A. Noronhia crassinodis H. Perrier [Ramandimbimanana 175];B. Noronhia crassiramosa H. Perrier [Rasoazanany et al. 326]; C. Noronhia cuspidata Hong-Wa [Hong-Wa 643]; D. Noronhia divaricata Scott-ELLiot [Rakotovao 5500].

Fig. 13. Noronhia cuspidata Hong-Wa. A. Fruiting branch; B. AbaxiaL side of Leaf bLade; C. Fruit.

Fig. 9. Distribution maps of species of Noronhia Stadtm.ex Thouars. N. christenseniana Dubard to N. domatifera Bosser.