Noronhia cochleata Labat, M. Pignal & O. Pascal

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 : 72-73

14. Noronhia cochleata Labat, M. Pignal & O. Pascal in Novon 9: 66. 1999 ( Fig. 7C ).

Typus: M AYOTTE: Mlima Combani, [12°50’S 45°10’E], 28.XII.1995, Pascal 281 (holo-: P [ P00075025 ]!; iso-: K [ K000691509 ] image seen, MO –5203140!, P [ P00075026 , P00075027 ]!) .

Description

Trees to 15 m tall, trunk to 15 cm diameter; young twigs cylindrical, 0.6-2.3 mm diameter, glabrous; bark medium gray, smooth. Leaves opposite, persistent; bud scales deciduous; blades medium green above, lighter below, oblong to elliptic, 6-12 3 2-4 cm, chartaceous, glabrous, domatia common, base acute to attenuate, margin flat to slightly undulate, apex acuminate, the acumen 6-15 mm long, midrib flat to slightly sunken above, raised below, secondary veins conspicuous, 8-13 per side, 4-18 mm apart, looping 1.5-4 mm from the margin; petiole yellow, 5-12 3 0.7-2.4 mm, not woody or only partially, glabrous. Thyrses geminate to fasciculate, pauciflorous, diffuse; peduncle 6-8 mm long, moderately pubescent; pedicel 1.5-9 mm long, moderately pubescent; calyx moderately pubescent outside, glabrous inside, lobes deltate, 0.5-1.2 3 0.8-1.4 mm; corolla pinkish outside, white inside, cupuliform to subrotate, 3-5.5 mm long, glabrous on both sides, the tube 1-3 mm long, lobes oblong to ovate, apex apiculate; corona present, 1-1.5 mm long, undivided; stamens 1.2-2 mm long, anthers oblong, 0.9-1.3 mm long; pistil 1.3-2 mm long, stigma capitate. Fruiting pedicel 3-10 3 0.8-1.2 mm; young fruits green, purplish black when mature, ovoid, 14-17 3 8-11 mm, surface smooth, covered with white dots, apex rostellate, the rostellum circular, rounded, with the persistent style; dry pericarp 0.3-0.5 mm thick; endocarp woody; seed 11.5-12 3 5-6 mm.

Distribution, ecology and phenology

Noronhia cochleata occurs in low- to mid-elevation humid forests on Mayotte in the Comoro Islands ( Fig. 9 ). It produces flowers and fruits from September to April.

Conservation status

The assessment was based on 15 collections representing 13 localities and indicated an EOO of just 161 km 2, an AOO of 40 km 2, and five subpopulations representing five locations, of which four are encompassed within protected areas (Réserves forestières de Benara, des Crêtes du Sud, de Majimbini et de Songoro Mbili). Subpopulations of N. cochleata will likely experience continuing decline in habitat quality and habit loss due to land conversion, therefore the species is assigned a preliminary status of “Endangered” [EN B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v)].

Notes

Noronhia cochleata can be recognized by its non-woody petioles, oblong to elliptic leaf blades bearing domatia, diffuse inflorescences and distinctly rostellate fruits. It differs mostly from N. comorensis by its non-woody (vs. woody) petioles, thyrsoid inflorescences (vs. fasciculate flowers), and pinkish-white (vs. yellow tinged reddish) corolla.

Additional specimens examined

MAYOTTE: Grande Terre, Chiconi, réserve forestière de Sohoa, 21.XII.2000, Barthelat 148 ( G, K, MO, P) ; Mamoudzou, Ilot Bouzi, 14.III.2001, Barthelat 327 ( G, K, MO, P) ; Bandrele, Contreforts du Choungui kely, 17.IX.2001, Barthelat 503 ( G, K, MO, P) ; Mamoudzou, La Convalescence, Réserve forestière de Majimbini, 12. I.2002, Barthelat 684 ( G, K, MO, P) ; ibid. loc., Mlima M’Tsapéré, 12°46’10”S 45°11’26”E, 300-400 m, 19.XI.2000, Labat 3258 ( B, G, K, MO, P, WAG) ; Combani, base du Mlima Combani, 12°48’27”S 45°09’13”E, 20.XI.2000, Labat 3261 ( K, MO, P) ; Réserve forestière du Benara, sommet du Bepilipli, 12°52’46”S 45°09’19”E, 550 m, 29.XI.2000, Labat 3308 ( BR, G, K, MO, P) ; Sommet du Mlima Choungi, 12°57’20”S 45°07’55”E, 500-640 m, 1.XII.2000, Labat 3339 ( G, K, MO, P, PRE) ; Shungui, 13.XI.1990, Ménager 15 ( MO, P) ; Mlima Choungi, [12°57’S 45°07’E], 16.XI.1995, Pascal 205 ( G, K, MO, P, WAG) ; Sohoa, 30.XI.1995, Pascal 257 ( MO, P) ; ibid. loc., 12°50’S 45°08’E, 160 m, 14.III.1996, Pascal 418 ( MO, P) ; Dapani, 150 m, 7. I.1997, Pascal 857 ( K, MO, WAG) ; Sazile Be, 12°58’39”S 45°12’01”E, 116. IV.1999, Pignal 1112 ( MO, P) .

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.