Uvaria osmantha Diels, Bot. Jahrb. Syst. 53: 436, 1915

Couvreur, Thomas L. P., Dagallier, Leo-Paul M. J., Crozier, Francoise, Ghogue, Jean-Paul, Hoekstra, Paul H., Kamdem, Narcisse G., Johnson, David M., Murray, Nancy A. & Sonke, Bonaventure, 2022, Flora of Cameroon - Annonaceae Vol 45, PhytoKeys 207, pp. 1-532 : 366-367

Uvaria osmantha Diels, Bot. Jahrb. Syst. 53: 436, 1915

Map 14E

= Uvaria scaberrima Exell, J. Bot. 73 (Suppl. 1): 3, 1935. Type. Angola. Cuanza Sul Province, Quibanga de Mucende, Libolo, Gossweiler J. 6311, 19 May 1915: holotype: BM[BM000554067]; isotypes: COI[COI00004869]; LISC[LISC000302].

Type.

Cameroon. East Region; Molundu, Mildbraed G.W.J. 4715, 1911: lectotype, sheet here designated: B[B 10 0153106]; isotypes: B[B 10 0153105]; HBG[HBG502489] .

Description.

Liana, 4-6 m tall, d.b.h. unknown. Indumentum of stellate or fasciculate hairs; old leafless branches glabrous, young foliate branches densely pubescent. Leaves: petiole 2-3 mm long, 1-2 mm in diameter, densely pubescent to tomentose, slightly grooved, blade inserted on top of the petiole; blade 4.5-12 cm long, 2-5 cm wide, elliptic to oblong, apex acuminate to acute, acumen 0.9-1.5 cm long, base rounded to cordate, papyraceous to subcoriaceous, discolorous, below completely covered with short stipitate stellate hairs when young and old, above pubescent with very short scabrid fasciculate hairs; midrib sunken or flat, above densely to sparsely pubescent when young, sparsely pubescent to glabrous when old, below densely pubescent when young and old; secondary veins 9 to 12 pairs, sparsely pubescent to glabrous above; tertiary venation reticulate, but indistinct. Individuals bisexual; inflorescences ramiflorous on young foliate branches, leaf opposed or extra axillary. Flowers with 9 perianth parts in 3 whorls, 1 to 3 per inflorescence; pedicel 10-30 mm long, 1-2 mm in diameter, densely pubescent; in fruit 20-30 mm long, 2-3 mm in diameter, pubescent; bracts 2, one basal and one towards the lower half of pedicel, basal bract 2 mm long, 2 mm wide; upper bract 2-3 mm long, 3-5 mm wide; sepals 3, valvate, completely fused, tearing at anthesis, 12-15 mm long, 8-10 mm wide, ovate, apex acute to acuminate, base truncate, pubescent outside, glabrous inside, margins flat; petals free, sub equal; outer petals 3, 25-35 mm long, 10-18 mm wide, oblong-obovate to oblong, apex acute, base truncate, green to light yellow, margins flat, densely pubescent outside, pubescent inside; inner petals 3, imbricate, 25-35 mm long, 10-18 mm wide, obovate to ovate, apex obtuse, base truncate, green to light yellow, margins flat, densely pubescent outside, pubescent inside; stamens 120 to 150, in 6 to 7 rows, 1-2 mm long, elongated; connective discoid, sparsely pubescent; staminodes absent; carpels free, 30 to 45, ovary 3-4 mm long, stigma coiled, glabrous. Monocarps stipitate, stipes 10-15 mm long, 1-2 mm in diameter, inserted laterally; monocarps 15 to 20, 15-30 mm long, 5-12 mm in diameter, cylindrical, apex apiculate, brown-tomentose, verrucose, slightly constricted between the seeds in dried material, brown when ripe; seeds 4 to 8 per monocarp, 7 mm long, 4-6 mm in diameter, ellipsoid; aril absent.

Distribution.

A central African species, known from Cameroon, Gabon, Democratic Republic of the Congo and Angola; in Cameroon known from the East region.

Habitat.

A fairly rare species in Cameroon; in lowland secondary or primary rain forests. Altitude 500-900 m a.s.l.

Local and common names known in Cameroon.

None recorded.

IUCN conservation status.

Not evaluated.

Uses in Cameroon.

None reported.

Notes.

Uvaria osmantha is distinguished by its strongly discolorous leaves with a rounded to cordate, scabrid above and completely covered with stellate hairs below. In addition, its sepals are completely fused in bud and tearing at anthesis (see notes under U. angolensis ) and its monocarps are cylindrical and brown-tomentose, with moderately long stipes (10-15 mm long) inserted laterally. In leaf shape and indumentum, U. osmantha resembles U. scabrida (also found in Cameroon, upper side of leaves also scabrous) and U. schweinfurthii (not found in Cameroon but in the Democratic Republic of the Congo, Central African Republic and East Africa) but the monocarps of the latter two are clearly different being sessile in the former and long (> 20 mm long) stipitate (more than twice as long as the monocarp) in the latter. In addition, U. scabrida has stipitate (not sessile) stellate hairs on lower leaf surface, much more prominent secondary leaf veins, percurrent tertiary venation, and a calyx with distinct sepals. Uvaria schweinfurthii also has a calyx with distinct sepals and monocarps inserted centrally on the stipes.

Specimens examined.

East Region: Prairies 10 km à l’E de Kinsassa village situé à 65 km au NNE de Moloundou par route Yokadouma 2.61°N, 15.47°E, 04 March 1971, Letouzey R. 10494 (P,YA); Prairie à 30 km WSW de Kinsasa village situé à 65 km NNE de Moloundou sur la route de Yokadouma 2.34°N, 15.28°E, 10 March 1971, Letouzey R. 10556 (P,YA) .

Figures

Map 14. A Uvaria klaineana B Uvaria mollis C Uvaria muricata var. yalingensis D Uvaria obanensis E Uvaria osmantha F Uvaria poggei G Uvaria scabrida H Uvariastrum insculptum I Uvariastrum pierreanum. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).