Noronhia comorensis S. Moore

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 : 74-75

15. Noronhia comorensis S. Moore in J. Bot. 58: 189. 1920 ( Fig. 7D ).

Typus: M AYOTTE: Forêt de Combani , [12°45’S 45°08’E], 3.XI.1884, Humblot 1376 (holo-: P [ P00184551 ]!; iso-: BM [ BM000021591 ] image seen, K [ K000233196 ] image seen, P [ P00184552 , P0018453 ]!) .

Description

Trees to 10 m tall, trunk to 10 cm diameter; young twigs cylindrical, 0.6-1.6 mm diameter, glabrous; bark light gray, smooth to slightly rugose. Leaves opposite, persistent; bud scales persistent; blades medium green above, lighter below, oblong to elliptic, sometimes obovate, 6.5-14 3 2-6 cm, chartaceous, glabrous, domatia absent, base acute to attenuate, margin flat to slightly undulate, apex acuminate, the acumen 6-20 mm long, midrib flat above, slightly raised below, secondary veins conspicuous, 8-12 per side, 7-17 mm apart, looping 1.5-4 mm from the margin; petiole medium to light gray, 3-7 3 1-1.8 mm, entirely woody, glabrous. Flowers fasciculate; pedicel 5-16 mm long, glabrous; calyx sparsely pubescent outside, glabrous inside, lobes triangular, 1-2 3 1-2.2 mm; corolla yellow tinged reddish, cupuliform, 5-7 mm long, glabrous on both side, the tube 3.5-6 mm long, lobes widely ovate, apex obtuse; corona present, 1.8-2.3 mm long, undivided; stamens 2-3.2 mm long, anthers widely obovate, 1.5- 2.6 mm long; pistil 2-3 mm long, stigma capitate. Fruiting pedicel 7-23 3 0.8-1.6 mm; young fruits green, dark brown when mature, ovoid, 10-16 3 8-10 mm, surface smooth, apex rostellate, the rostellum flattened, rounded, with the persistent style; dry pericarp 0.2-0.4 mm thick; endocarp woody; seed 8.5-12 3 4-7 mm.

Distribution, ecology and phenology

Noronhia comorensis occurs in low- to mid-elevation humid forests in the Comoro Islands (Anjouan, Grande Comore, Mayotte, and Moheli) ( Fig. 9 ). It produces flowers and fruits from September to May.

Conservation status

Based on 15 collections representing eight localities, the assessment provided an EOO of 966 km 2, an AOO of 32 km 2, and seven subpopulations representing seven locations, of which three occur within protected areas (Réserves forestières de Benara, des Crêtes du Nord et de Majimbini). A decline in EOO and AOO as well as in habitat quality will very likely occur due to land conversion affecting the subpopulations in Anjouan, Grande Comore and Moheli, which are not encompassed within protected areas. Therefore, N. comorensis is assigned a preliminary status of “Vulnerable” [VU B1ab(i,ii,iii,iv,v)+2ab(i,ii, iii,iv,v)].

Notes

Noronhia comorensis can be recognized by its chartaceous, oblong to elliptic leaf blades, fasciculate, yellow flowers, and distinctly rostellate fruits. It differs from N. cochleata by the features mentioned under that species.

Additional specimens examined

COMOROS: Anjouan ( Ndzouani ), 1 km E of Lingoni, 200- 200 m, 14.IX.1991, Attoumane 13 ( MO) ; Anjouan ( Ndzouani ), Lavanchie s.n. ( P) ; Grande Comore ( Ngazidja ), Iconi , 11°43’48”S 43°14’03”E, 27 m, 23.V.2006, Labat 3677 ( K, MO, P) ; Moheli (Mwali), piste du Bajo au sommet du M’Ze , 12.XI.1970, Jacquemin 860 J ( P) ; Miringoni, Mdawnyombe Chalet Saint-Antoine , 12°17’18”S 43°39’51”E, 688 m, 29.V.2006, Labat et al. 3729 ( K, MO, P) . MAYOTTE: Chinconi, Grande Terre, Coconi , 5.II.2001, Barthelat & M’Changama 282 ( G, MO, P) ; Dembeni, Réserve forestière de Benara , 7.IX.2001, Barthelat 486 ( G, K, MO, P) ; Chembenyoumba, Hachirongou , 9.X.2001, Barthelat 537 ( G, K, MO, P) ; Mamoudzou, La Convalescence , Réserve forestière de Majimbini , 11.I.2002, Barthelat & Sifary 673 ( G, K, MO, P) ; ibid. loc., 11.I.2002, Barthelat & Sifary 675 ( G, K, MO, P) ; ibid. loc., Réserve de Majimbini, Mlima M’Tsapere , 12°46’10”S 45°11’26”E, 300- 400 m, 19.XI.2000, Labat 3257 ( G, K, MO, P) ; ibid. loc., 23.XI.2000, Labat 3281 ( G, K, MO, P) ; Piste de Convalescence, 11.XII.1990, Ménager S52 ( MO, P) ; Hachiroungou , [12°43’S 45°04’E], 450 m, 16.IV.1996, Pascal 507 ( MO, P) ; Convalescence , 400 m, 18.IX.1996, Pascal 666 ( BR, G, MO, NY, P, WAG)

Figures

Fig. 7. Photographs of Noronhia Stadtm.ex Thouars. A. Noronhia christenseniana Hong-Wa [Ratovoson 1280]; B. Noronhia clarinerva Hong-Wa [Nusbaumer 821]; C. Noronhia cochleata Labat, M. PignaL & O. PascaL [Labat 3258]; D. Noronhia comorensis S. Moore [Barthelat 537]; E. Noronhia cordifolia (Labat, M. PignaL & O. PascaL) Hong-Wa & Besnard [Barthelat 788].

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