Anonidium brieyi De Wild., Repert. Spec. Nov. Regni Veg. 13: 383, 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 : 47-52

Anonidium brieyi De Wild., Repert. Spec. Nov. Regni Veg. 13: 383, 1914

Figs 9 , 10 ; Map 1H

≡ Anonidium mannii var. brieyi (De Wild.) R.E.Fr., Acta Hort. Berg. 10: 80, 1930.

= Anonidium friesianum Exell, J. Bot. 70, Suppl. Polypet.: 211, 1932. Type. Angola. Mayombe, Buco Zau, Gossweiler J. 6690, 16 Sep 1916: lectotype, designated here: LISC[LISC000056]; isolectotypes: COI[COI00004880]; BM[BM000546826, BM000546827]; LISC[LISC000054, LISC000055, LISC000057, LISC000058, LISC000059, LISC000060, LISC000061, LISC000062, LISC000063].

Type.

Democratic Republic of the Congo. Bas-Congo; Ganda-Sundi, de Briey J. 86, 1911: lectotype, here designated: BR[BR8822635]; isolectotype: BR[BR8822642] .

Description.

Tree, 15-25 m tall, d.b.h. up to 35 cm; stilt roots or buttresses absent. Indumentum of simple hairs; old leafless branches glabrous, young foliate branches sparsely pubescent to glabrous. Leaves: petiole 3-10 mm long, 2-5 mm in diameter, sparsely pubescent, soon becoming glabrous, slightly grooved, blade inserted on top of the petiole; blade 37-50 cm long, 10-16 cm wide, oblong, apex rounded to abruptly acuminate, acumen 2-3.5 cm long, base rounded, subcordate, subcoriaceous to coriaceous, below sparsely pubescent when young, glabrous when old, above glabrous when young and old, concolorous; midrib impressed, above glabrous when young and old, below sparsely pubescent when young, glabrous when old; secondary veins 14 to 16 pairs, glabrous above; tertiary venation reticulate. Individuals dioecious; inflorescences cauliflorous or on leafless branches, axillary; peduncle 50-115 mm long, 3-10 mm in diameter, woody, hanging or semi erect from the trunk, glabrous. Flowers with 9 perianth parts in 3 whorls, 1 to 10 per inflorescence, male and female inflorescences similar; pedicel 10-35 mm long, 2-4 mm in diameter, glabrous; bracts, 1 to 2 basal and one upper towards the upper of pedicel, basal bracts 5-10 mm long, 5-10 mm wide; upper bract directly under the calyx, amplexicaul, 12-21 mm long, 10-20 mm wide; sepals 3, valvate, free, 20-40 mm long, 14-18 mm wide, triangular, apex long acuminate, gradually tapering into an acute apex, base truncate, green, densely pubescent outside, glabrous inside, margins flat; petals free, sub equal; outer petals 3, 35-60 mm long, 10-18 mm wide, narrowly elliptic to obovate, apex acute to attenuate, base attenuate, green turning yellow, margins flat, pubescent outside, pubescent inside; inner petals 3, valvate, 30-50 mm long, 9-16 mm wide, narrowly elliptic, apex acute, base truncate, green turning yellow, margins flat, pubescent outside, pubescent inside; stamens in male flowers: 500 to 700 inserted on a conical receptacle, in 14 to 17 rows, 3.5-5 mm long, oblong, connective truncate, sparsely pubescent, green to cream-yellow; carpels in female flower (see notes) 220 to 260, ovary 2-3 mm long, stigma capitate, glabrous; staminodes absent. Whole fruits not seen, label information: ca. 20 cm long, ca. 10 cm in diameter [taken from descriptions on specimens Hallé & Villiers 4505, P02032580], white [taken from Cheek 10240 P00956188]; seed 1, 40-48 mm long, 17-23 mm wide, ellipsoid; aril absent.

Distribution.

A central African species, known from Cameroon, Gabon, Republic of the Congo and Angola (Cabinda); in Cameroon known from the Littoral and South-West regions.

Habitat.

An uncommon species, in lowland primary or old secondary rain forests. Altitude 100-350 m a.s.l.

Local and common names known in Cameroon.

None recorded.

IUCN conservation status.

Not evaluated.

Uses in Cameroon.

None recorded.

Notes.

Anonidium brieyi differs from A. mannii by its usually larger leaves and the narrower inner (10-18 mm wide versus 15-25 mm in A. mannii ), and the upper bract inserted just under the calyx (versus near the middle of the pedicel in A. mannii ). Three collections seen have strictly female flowers (Couvreur 1132, WAG; Hallé & Villiers 4505, [P02032580]; Sita 712 [MPU411091). The first author’s field observations failed to see any stamens in the thus apparently female flowers (Fig. 10J ). A note by Le Testu (Le Testu 1641 [P02032574]) also indicates that the species is dioecious. This suggests that A. brieyi is a strictly dioecious species (male and female flowers on different individuals) rather than androdioecious as in the other species of Anonidium ( Le Thomas 1969b). This is the first time this is suggested to occur in this species as only male flowers were described to date. Anonidium letestui Pellegr. (endemic to Gabon) has functionally female flowers, but has a small row of sterile stamens at the base ( Le Thomas 1969b), something not observed in the two female specimens examined in A. brieyi (Fig. 10J ). Variation of sexual systems within genera (e.g. androdioecious and dioecious species) has been reported in African Annonaceae such as Monanthotaxis ( Hoekstra et al. 2021) or Uvariopsis ( Couvreur and Luke 2010).

Le Thomas (1969b) recognized this species as a variety of A. mannii ( A. mannii var. brieyi (De Wild.) Fries), however, the morphological differences in addition to its dioecious nature described above warrant it to be retained at the species level for now. Nevertheless, a phylogeographic study of A. mannii based on hundreds of nuclear markers inferred a nested position of A. brieyi (population collected around reference number Couvreur 1132, here identified as A. brieyi ) within A. mannii ( Helmstetter et al. 2020). This sheds further doubt on the delimitation between these two species and needs further study.

Narrowly elliptic petals are also found in the Gabonese species A. floribundum Pellegr. (not recorded for Cameroon to date). However, this latter species is a small tree up to 4 or 5 m tall, the inflorescences are shorter with fewer flowers, and it is androdioecious ( Le Thomas 1969b).

Two herbarium specimens (Cheek 10240, Cameroon; Hallé & Villiers 4505, Gabon) indicate that the collection had fruits, but we were unable to locate them. Cheek 10240 states the fruits are white. Collection Cheek 12040 was identified as A. mannii in the check list of the plants of Mt Kupe ( Cheek et al. 2004, p. 236). Four of the type sheets of the name A. friesianum have seeds (Gossweiler 6690, LISC000055, LISC000058, LISC000060, LISC000063). On sheets LISC000055 and LISC000061 there are large narrow structures (18 cm by 3.5 cm) which we cannot identify, either being a dried fruit or part of the bark (?).

The sheet Cheek 10240 from P (P00956188) is a mixed collection. The leaves belong to a species of Uvariopsis (probably Uvariopsis connivens ), and not A. brieyi . The flowers however are from A. brieyi. The other sheets we have seen appear to have the correct leaves (K, WAG [WAG.1378838])

Finally, for the type of Anonidium friesianum , among the 10 sheets of Gossweiler 6690 available at we did not designate one sheet as lectotype because every sheet has important information (leaves, seeds, leaves) and should be considered as a single collection. Among the 10 sheets of Gossweiler 6690 available at LISC for the type of Anonidium friesianum , we selected a single sheet as the lectotype (LISC000056). Indeed, according to the ICBN, different sheets are considered as a single specimen only if they are cross-referenced (e.g. "Sheet I", "Sheet II") which is not the case here. The selected sheet (LISC000056) was the only one that had a leaf and a flower (but broken) thus being the most complete. The other sheets only had either just leaves, or inflorescences or flowers or seeds.

Specimens examined.

Littoral Region: Loum Forest Reserve , 4.73°N, 9.731°E, 16 April 2005, Onana J.M. 3101 (K). South-West Region : Banga, 4.55°N, 9.416°E, 01 March 1956, Binuyo A. 35606 (FHO); Southern Bakundu FR, 4.48°N, 9.350°E, 13 March 1948, Brenan J.P.M. 9410 (K,P); Just west of Loum, 4.73°N, 9.729°E, 03 December 1999, Cheek M. 10240 (K,MO,P,WAG,YA); S Bakundu FR, 4.49°N, 9.374°E, 09 April 1951, Olorunfemi J. 30508 (K); 5 km S of Kumba on Buea /Douala Road, 4.65°N, 9.39°E, 21 June 1983, Thomas D.W. 2188 (MO,P,WAG) .

Figures

Map 1. A Afroguatteria discostigma B Annickia affinis C Annickia chlorantha D Annickia letestui E Annickia polycarpa F Annona senegalensis G Annona senegalensis subsp. oulotricha H Anonidium brieyi I Anonidium mannii. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).

Figure 9. Anonidium mannii A leaf B male inflorescence, note upper bract inserted towards lower part of pedicel C receptacle of male flower, all petals removed D stamen E receptacle of bisexual flower, note small row of stamens at base of carpels F longitudinal section of bisexual flower G stamen of bisexual flower, front view H two free carpels, showing basal ovules I fruit, note syncarpous nature, referred to as pseudosycarpous J seed, side view. Anonidium brieyi K flower, note narrow petals A from Le Testu 9169 B-D from Le Testu 9509 E-H from Le Testu 7269 I from Nigerian tree photo J from Le Testu s. n. K from Le Testu 1641. Drawings by Helene Lamourdedieu, Publications Scientifiques du Museum national d'Histoire naturelle, Paris; modified from Le Thomas (1969 b; pl. 60, p. 331).

Figure 10. Anonidium manni A habit, A. manni is the species with white trunk in the center B base of leaf blade, upper side C pseudosyncarpous fruit, note hand for size D Narcisse Kamdem holding an inflorescence E detail of flower, side view F detail of receptacle of bisexual flower, note 2 to 3 rows of stamens at base. Anonidium brieyi G trunk with semi erect inflorescences H leaf, upper side I flower, side view, note narrow petals J detail of receptacle in female flower, note absence of stamens at base of carpels K flower, top view showing insertion of upper bract just belong the calyx A no voucher, Gabon B, C Couvreur 449, Otottomo, Cameroon D, F Couvreur 696, Campo, Cameroon E Couvreur 1207, Masea, Cameroon G-K Couvreur 1132, Gabon. Photos Thomas L. P. Couvreur.