Monanthotaxis gracilis (Hook.f.) P.H.Hoekstra, Taxon 66 (1): 14, 2017

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 : 206-209

Monanthotaxis gracilis (Hook.f.) P.H.Hoekstra, Taxon 66 (1): 14, 2017

Fig. 59 ; Map 7I

≡ Uvaria gracilis Hook.f., Niger Fl.: 210, 1849. Oxymitra gracilis (Hook.f.) Sprague & Hutch., Bull. Misc. Inform. Kew 6: 154, 1916; Richella gracilis (Hook.f.) R.E.Fr., Nat. Pflanzenfam., ed. 2, 17a (2): 139, 1959; Friesodielsia gracilis (Hook.f.) Steenis, Blumea 12: 359, 1964.

= Oxymitra platypetala Benth., Trans. Linn. Soc. London 23(3): 472, 1862; Cleistopholis platypetala (Benth.) Engl. & Diels, Monogr. Afrik. Pflanzen.-Fam. 6: 34, 1901. Type. Sierra Leone. Southern Province, Bagroo river, Mann G. 857, Apr 1896: holotype: K[K00198952].

= Unona millenii Engl. & Diels, Monogr. Afrik. Pflanzen.-Fam. 6: 40, 1901. Type. Nigeria. Lagos State, Lagos, Millen H. 149, Mar 1896: holotype: K, not seen.

= Oxymitra rosea Sprague & Hutch., Bull. Misc. Inform. Kew 6: 154, 1916; Richella rosea (Sprague & Hutch.) R.E.Fr., in Engler & Prantl Nat. Pflanzenfam., ed. 2, 17a (2): 139, 1959; Friesodielsia rosea (Sprague & Hutch.) Steenis, Blumea 12: 361, 1964. Type. Nigeria. Cross River State, Oban, Talbot P.A. 199, 1911: holotype: BM[BM000547067].

Type.

Sierra Leone. no region; no location, Don G. s.n., no date: holotype: BM[BM000547066] .

Description.

Shrub to liana, 4-20 m tall, d.b.h. 10-20 cm. Indumentum of simple hairs; old leafless branches sparsely pubescent to glabrous, light grey in color, young foliate branches pubescent with very short appressed to ascending hairs 0.1 mm long. Leaves: petiole 2-4 mm long, 0.5-1 mm in diameter, pubescent, grooved, blade inserted on top of the petiole; blade 4-16.5 cm long, 1.4-5.7 cm wide, obovate to oblanceolate, apex acuminate to acute, acumen ca. 2 cm long, base cuneate to subcordate, subcoriaceous, below sparsely pubescent to glabrous when young, glabrous when old, above glabrous when young and old, discolorous, whitish below; midrib depressed, above glabrous when young and old, below sparsely pubescent when young, glabrous when old; secondary veins 7 to 10 pairs, glabrous above; tertiary venation percurrent. Individuals bisexual; inflorescences ramiflorous on old leafless branches, leaf opposed to extra axillary. Flowers with 9 perianth parts in 3 whorls, 1 to 3 per inflorescence; pedicel 15-45 mm long, ca. 0.5 mm in diameter, pubescent; in fruit 25-50 mm long, 0.5-1 mm in diameter; basal bract 1-2 mm long, 0.5-1 mm wide; upper bract 2-3 mm long, ca. 1 mm wide, lanceolate in shape; sepals 3, valvate, basally fused, 3-6 mm long, 4-5 mm wide, ovate, apex obtuse, base truncate, sparsely pubescent outside, glabrous inside, margins flat; petals free, outer petals longer than inner, inner petals entirely covered in bud; outer petals 3, 12-30 mm long, 7-12 mm wide, elliptic, apex obtuse, base truncate, light yellow to light green, margins flat, pubescent outside, pubescent inside; inner petals 3, valvate, 5-9 mm long, 3-5 mm wide, ovate to rhombic, apex acute, base truncate, margins flat, pubescent outside, sparsely pubescent to glabrous inside; stamens 80 to 125, in 3 to 5 rows, ca. 1 mm long, linear to oblong; connective globose, glabrous; staminodes absent; carpels free, 17 to 24, ovary 1-2 mm long, stigma elongate, pubescent. Monocarps stipitate, stipes 4-8 mm long, 2 mm in diameter; monocarps 10 to 20, red when ripe, 13-35 mm long, 4-5 mm in diameter, moniliform, ellipsoid to globose, apex apiculate, densely pubescent, pubescent, constricted around seeds when more than 1, red when ripe; seeds 1 to 5 per monocarp, ca. 6 mm long, ca. 4 mm in diameter, ellipsoid; aril absent.

Distribution.

A mainly west African species, from Sierra Leone to Nigeria, just reaching into Cameroon where known from the South-West region.

Habitat.

A rare species in Cameroon; in primary and secondary rain forests, swamp forests and gallery forests, on river banks and summit ridges. Altitude: 100 m a.s.l.

Local and common names known in Cameroon.

None recorded.

Preliminary IUCN conservation status.

Least Concern (LC) ( Hoekstra et al. 2021).

Uses in Cameroon.

None reported.

Notes.

Monanthotaxis gracilis is distinguished by its light-grey branches, very short hairs on the branches and pedicels, a small lanceolate upper bract, its long slender flowering pedicels and ellipsoid flower buds and elliptic outer petals.

This species is only known from a single collection in Cameroon to date.

Specimens examined.

South-West Region: Korup National Park , 5.01°N, 8.8°E, 15 June 2000, van der Burgt X.M. 614 (WAG) .

Figures

Map 7. A Monanthotaxis diclina B Monanthotaxis dielsiana C Monanthotaxis elegans D Monanthotaxis enghiana E Monanthotaxis ferruginea F Monanthotaxis filamentosa G Monanthotaxis foliosa H Monanthotaxis glaucifolia I Monanthotaxis gracilis. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).

Figure 59. Monanthotaxis gracilis A Flowering branch B flower, side view C sepal, inner view D outer petal, inner view E inner petal; inner view F stamens, side and front views G carpel, side view and detail of ovules H fruit, note persistent sepals. Monanthotaxis montana I flowering branch J flower, side view K inner petal, inner view L flower, all petals removed, side view M stamen, front view N carpel, side view and details of ovules O fruiting branch P seed, side view. Monanthotaxis hirsuta Q flowering branch R inner petal, inner view S stamen, front view T fruiting branch A from Meikle 956 B, C from Akpabla 1106 D-G from Dalziel 1096 H from FHI 28906 I-P unknown Q-S from Chevalier 14817 T from FHI 19738. Drawings by Helene Lamourdedieu, Publications Scientifiques du Museum national d'Histoire naturelle, Paris.