Noronhia spinifolia, Hong-Wa, 2016, 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 : 251-252

78. Noronhia spinifolia Hong-Wa , spec. nova ( Fig. 63 ).

Typus: MADAGASCAR. Prov. Antsiranana: SAVA, Vohémar, Daraina , Bekaraoka Sud , 13°10’17”S 49°42’12”E, 149 m, 31.V.2005, Hong-Wa et al. 278 (holo-: MO-6615554!; iso-: CNARP!, G [ G00341617 ]!, K!, P [ P04254208 ]!, TAN!) .

Diagnosis

Noronhia spinifolia Hong-Wa can be distinguished from other congeneric species by its narrowly linear leaf blades that are terminated by a spiny apex.

Description

Shrubs to 6 m tall, trunk to 8 cm diameter; young twigs cylindrical, 0.6-1.4 mm diameter, glabrous; bark medium gray, smooth. Leaves opposite, persistent; bud scales rarely persistent; blades light green above, darker below, linear, 4-9.5 3 0.3- 0.7 cm, coriaceous, glabrous, domatia absent, but can be present on stems, base rounded, margin revolute, apex acute and spiny, the point 1-2 mm long, midrib flat above, slightly raised below, secondary veins inconspicuous, 8-14 per side, 3-13 mm apart, looping 0.4-1 mm from the margin; petiole medium gray, 1-4 3 0.5-1.5 mm, entirely woody, glabrous. Flowers solitary to geminate; pedicel 5-14 mm long, glabrous; calyx glabrous on both sides, lobes triangular, 1-1.7 3 0.4-0.7 mm; corolla cream-white, urceolate, 5-7 mm long, glabrous on both sides, the tube 4-6 mm long, lobes deltate, apex truncate; corona present, 1.4-2 mm long, slightly lobed; stamens 1.7-2.3 mm long, anthers oblong to obovate, 1.1-1.6 mm long; pistil 3-3.5 mm long, stigma bilobed. Fruiting pedicel 6-12 3 0.5-1 mm; young fruits green, reddish when mature, ovoid, 8-10 3 6-7 mm, smooth to rugose, apex apiculate; dry pericarp 0.3 mm thick; endocarp crustaceous; seed 7 3 5 mm.

Etymology

The leaf blade is terminated by a sharp, spine-like apex, which characterizes this spe-cies and was used as the basis for the specific epithet.

Distribution, ecology and phenology

Noronhia spinifolia occurs in low-elevation semi-deciduous forests on basement rocks and limestones in the north, particularly around Daraina and Montagne des Français ( Fig. 62 ). It produces flowers and fruits from October to May.

Conservation status

The assessment included 11 collections representing 10 localities and indicated an EOO of 708 km 2, an AOO of 36 km 2, and seven subpopulations representing five locations, of which three occur within the newly established protected areas of Loky-Manambato and Montagne des Français. Forest exploitation and land conversion will cause decline in habitat quality and loss of mature individuals at some of the locations. Therefore, N. spinifolia is assigned a preliminary status of “Endangered” [EN B1ab(iii,v)+2ab(iii,v)].

252 Boissiera 70

Notes

Noronhia spinifolia closely resembles N. linearifolia , from which it differs by its acute and spiny (vs. retuse) leaf apex, cream-white (vs. reddish brown) flowers, and crustaceous (vs. woody) endocarp. It can be recognized by its narrowly linear leaf blades with a spiny apex, solitary to geminate cream-white flowers, and apiculate fruits.

Paratypi

MADAGASCAR. Prov. Antsiranana: Vohémar, Daraina , Mahatsara , Ambilondambo , 13°09’55”S 49°38’52”E, 292 m, 17.XI.2005, Be et al. 297 ( CNARP, G, MO, P, TAN) ; Mahavanona, Andranomanitra, Montagne des Français , 12°22’07”S 49°20’54”E, 195 m, 14.XII.2006, Be et al. 324 ( CNARP, MO, P, TAN) ; Daraina, Ankijabe, forêt de Binara , 13°15’S 49°37’E, 500 m, 6.XI.2001, Gautier & Ravelonarivo 4077 ( Daraina , G, K, MO, TEF) ; Daraina, forêt de Solaniampilana-Maroadabo, 13°05’53”S 49°34’51”E, 100 m, 6.III.2004, Gautier et al. 4444 ( Daraina , G, K, MO, TEF) ; Daraina, forêt de Bekaraoka, 13°04’58”S 49°42’04”E, 140 m, 22.XI.2006, Gautier & Chatelain 4897 ( Daraina , G, K, MO, TEF) ; Daraina, Ambararatabe, 13°04’50”S 49°41’44”E, 80 m, 26.X.2004, Maraia 13 ( Daraina , G, K, NEU, P, TEF) ; Daraina, Mantamena, part of Bekaraoka Range , 7 km NE of Daraina, 14°60’S 49°42’E, 112-330 m, 14.XII.1990, Meyers 235 ( K, MO, P, TAN) ; ibid. loc., 13°08’S 49°42’E, 112-330 m, 1991, Meyers 292 ( MO, P, TAN) ; Daraina, Befarafara, forêt de Solanampilana , 13°05’26”S 49°34’32”E, 100 m, 15.XI.2005, Rakotonandrasana et al. 991 ( CNARP, G, MO, P, TAN) ; ibid. loc., Ampasimbe , 13°06’02”S 49°34’39”E, 186 m, 11.XII.2006, Rakotondrajaona et al. 403 ( CNARP, MO, P, TAN) ; Vohémar , versant E du massif de l’Ankerana (partie S du massif de Mafokovo), 50-450 m, 17.XII.1966, Service Forestier 27353 ( P, TEF) .

Figures

Fig. 63. Noronhia spinifolia Hong-Wa.

Fig. 62. Distribution maps of species of Noronhia Stadtm. ex Thouars.N. similis Hong-Wa to N. tubulosa H. Perrier.