Artabotrys rufus De Wild., Bull. Jard. Bot. Etat Bruxelles 4: 386, 1914

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 : 71-75

Artabotrys rufus De Wild., Bull. Jard. Bot. Etat Bruxelles 4: 386, 1914

Figs 16 , 17 ; Map 2H

= Artabotrys boonei De Wild., Repert. Spec. Nov. Regni Veg. 13: 383, 1914. Syn. nov. Type. Democratic Republic of the Congo. Orientale, Nala, Boone A. 80, 1911: lectotype, sheet here designated: BR[BR0000008820365]; isotype: BR[BR0000008820372].

= Artabotrys dahomensis Engl. & Diels, Notizbl. Königl. Bot. Gart. Berlin 2: 299, 1899. Syn. nov. Type. Benin: Dahome, Newton s.n., 1886: holotype: B[B 10 0153018].

= Artabotrys setulosus Mildbr. & Diels, Bot. Jahrb. Syst. 53. 447, 1915. Type. Cameroon. East Region, Mulundou, Mildbraed G.W.J. 4999, 26 Jan 1911: lectotype, here designated: HBG[HBG502545].

Type.

Democratic Republic of the Congo. Equateur; Likimi, Malchair L. 274, 20 Avr 1910: holotype: BR[BR0000008820297]

Description.

Liana, to 20 m tall, d.b.h. 3-5 cm. Indumentum of simple hairs; old leafless branches sparsely pubescent, young foliate branches hirsute, with erect hairs. Leaves: petiole 2-4 mm long, 1-2 mm in diameter, hirsute, slightly grooved, blade inserted on top of the petiole; blade 8-14 cm long, 3.5-5.5 cm wide, oblong to obovate, apex acuminate, acumen 0.5-1 cm long, base rounded to subcordate or obtuse, papyraceous, below pubescent when young and old with long appressed hairs, above glabrous when young and old, concolorous; midrib impressed, above glabrous when young and old, below pubescent when young and old; secondary veins 9 to 12 pairs, glabrous above; tertiary venation reticulate. Individuals bisexual; inflorescences ramiflorous on old leafless branches, leaf opposed. Flowers with 9 perianth parts in 3 whorls, 1 to 3 per inflorescence, hook-shaped peduncle 4-7 mm long; pedicel 3-5 mm long, ca. 1 mm in diameter, pubescent to sparsely hirsute; in fruit 3-15 mm long, ca. 2 mm in diameter, pubescent; bracts caduceus, not seen; sepals 3, valvate, free, 5-7 mm long, 2-4 mm wide, triangular, apex acute, base truncate, green, hirsute outside, glabrous inside, margins flat; petals free, sub equal, green turning yellow; outer petals 3, 10-20 mm long, 3-4 mm wide, very narrowly elliptic to linear, apex acute, base rounded to broad and concave, green turning bright yellow, margins flat, recurved inwards in vivo, densely appressed-pubescent outside, appressed-pubescent to glabrous inside; inner petals 3, valvate, 12-20 mm long, 2-3 mm wide, very narrowly elliptic to linear, apex acuminate to acute, base broad and concave, green turning bright yellow, margins flat, recurved inwards in vivo, appressed-pubescent outside, appressed-pubescent inside; stamens 60 to 70, in ca. 5 rows, ca. 1 mm long, broad; connective discoid, glabrous, green; staminodes absent; carpels free, 8 to 10, ovary ca. 1 mm long, stigma capitate, glabrous. Monocarps sessile, 5 to 11, 12-15 mm long, 5-6 mm in diameter, ellipsoid to fusiform, apex apiculate, glabrous, smooth, not ribbed, red when ripe; seeds 1 to 2 per monocarp, 10-12 mm long, 5 mm in diameter, ellipsoid to oblong; aril absent.

Distribution.

A mainly central African species, from Benin to Nigeria and Cameroon to the Republic of the Congo and in the Democratic Republic of the Congo; in Cameroon known from the Central and East regions.

Habitat.

A fairly common species, in secondary lowland or premontane rain forests. Altitude 400-900 m a.s.l.

Local and common names known in Cameroon.

nginda ( pygmée-bibaya) ( Letouzey 1964).

IUCN conservation status.

Not evaluated.

Uses in Cameroon.

None recorded.

Notes.

Artabotrys rufus is distinguished by the hirsute pubescence of the young foliate branches, petioles, peduncles and flowering pedicels, its leaves that are elliptic, apiculate and less than 14 cm long, with long (1-2 mm) appressed hairs on the lower side of the leaf blade and a rounded to subcordate or obtuse base, a short peduncle (generally less than 7 mm long), petals with long dense brown hairs and smooth apiculate monocarps. The tertiary venation is also clearly visible forming clear loops towards the margins of the leaves.

Artabotrys rufus resembles A. velutinus being pubescent, but the pubescence of A. velutinus is not hirsute, with shorter hairs and more tomentose on the young foliate branches and petioles. The petals are also very similar being curved inwards, giving them the appearance of a tube. It is possible that both names are synonymous. Artabotrys rufus is also very close morphologically to the west African species A. hispidus Sprague & Hutch. by its hirsute pubescence and the shape of the leaves and flowers. It is also very possible that these names are synonymous. Several specimens from Cameroon where identified as A. hispidus , but upon closer look we have identified them as belonging to A. rufus . Several authors ( Boutique 1951b; Le Thomas 1969b) have suggested that the name A. rufus might be synonym with the east African A. rupestris Diels, although Verdcourt didn’t recognize this synonymy ( Verdcourt 1971a) suggesting differences in the leaves.

We here synonymize the names A. boonei and A. dahomensis with A. rufus. The former name was considered a synonym of A. velutinus ( Lebrun and Stork 1991), but the type clearly suggests it is a synonym of A. rufus (if the latter is really distinct from A. velutinus ).

More detailed studies across the range of these species ( A. hispidus , A. rufus , A. rupestris and A. velutinus ) are needed to determine if there is one single widespread species from west to east Africa (possibly with different infraspecific taxa), or if there are several different species possibly grouped into a species complex ( Hawthorne and Jongkind 2006).

Specimens examined.

Central Region: Fébé Mount, 3.91°N, 11.48°E, 30 March 1962, Breteler F.J. 2717 (A,BR,K,P,WAG,YA); Mont Mbam Minkon on trail 5 km from Nkol Nyada village On top of small hill, 3.97°N, 11.40°E, 21 March 2013, Couvreur T.L.P. 418 (MPU,WAG,YA); Nachtigal, 4.35°N, 11.63°E, 01 July 1964, de Wilde W.J.J.O 2779 (P,WAG,YA); Nkolbison, 3.88°N, 11.45°E, 02 November 1964, de Wilde W.J.J.O 3715 (BR,K,P,WAG); Left bank Sanaga river near Ferry Nachtigal ca 20 km N of Obala, 4.34°N, 11.64°E, 29 April 1965, Leeuwenberg A.J.M. 6011 (B,BR,C,K, MO,P,WAG,YA). East Region : Dimako, 4.38°N, 13.57°E, 02 August 1961, Breteler F.J. 1752 (P,YA); Bertoua 15 km along road to Deng Deng, 4.66°N, 13.63°E, 31 August 1961, Breteler F.J. 1825 (WAG); Bamékok (Batouri), 4.2°N, 14.15°E, 16 April 1962, Breteler F.J. 2825 (P,WAG); 60 km south of Yokadouma 5 km south of Maséa village, 3.10°N, 14.84°E, 06 March 2019, Couvreur T.L.P. 1211 (MPU,WAG,YA); A 25 km au NE de Bangé km 75 route Yokadouma-Moloundou, 3.02°N, 15.12°E, 25 May 1963, Letouzey R. 5147 (P,YA); Mbatika-Malen 20 km de Moloundou route Yokadouma 2.03°N, 15.22°E, 22 April 1971, Mezili P. 193 (P,YA); Moloundou near Lokomo Bumba and Bange, 2.08°N, 15.25°E, 26 January 1911, Mildbraed G.W.J. 4350 (B,HBG); Forêt inhabitée entre Yokaduma et Assobam, 3.52°N, 15.05°E, 24 April 1911, Mildbraed G.W.J. 4999 (B,HBG) .

Figures

Map 2. A Artabotrys aurantiacus B Artabotrys aurantiacus var. multiflorus C Artabotrys congolensis D Artabotrys dielsianus E Artabotrys insignis F Artabotrys insignis var. batesii G Artabotrys jacques-felicis H Artabotrys rufus I Artabotrys thomsonii. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).

Figure 16. Artabotrys rufus A leaf, upper side B base of leaf blade, upper side C base of leaf bade, lower side D branch, note erect hairs E flowering branch F flower, side view G detail of receptacle, 4 petals removed H flower, top view A-H Couvreur 854, Gabon. Photos Thomas L. P. Couvreur.

Figure 17. Artabotrys thomsonii A flowering branch B outer petal, inner view C inner petal, inner view D flowering receptacle, petals removed E stamens, front and side views F carpel, side and detail of ovules G fruiting peduncle. Artabotrys rufus H flowering branch I flowering receptacle with one outer petal removed J outer petals, outer view and inner views K inner petals, inner and outer views L flowering receptacle, petals removed M stamen N carpel, side view and detail of ovule O fruiting peduncle A-G from Le Testu 9249 H-N from Hall 3193; 15 from Hall 3528. Drawings by Helene Lamourdedieu, Publications Scientifiques du Museum national d'Histoire naturelle, Paris; modified from Le Thomas (1969 b, pl. 23, p. 441 (A. rufus )).