Afroguatteria discostigma (Diels) X.Guo & R.M.K.Saunders, Taxon 66 (1): 13, 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 : 26-29

Afroguatteria discostigma (Diels) X.Guo & R.M.K.Saunders, Taxon 66 (1): 13, 2017

Fig. 4 ; Map 1A

Cleistopholis discostigma ≡ Cleistopholis discostigma Diels, Bot. Jahrb. Syst. 39: 474, 1907; Oxymitra discostigma (Diels) Ghesq. ex Pellegr., Bull. Soc. Bot. France, 66, 1949; Richella discostigma (Diels) R.E.Fr., in Engler & Prantl Nat. Pflanzenfam., ed. 2, 17a (2): 139, 1959; Friesodielsia discostigma (Diels) Steenis, Blumea 12: 359, 1964.

Type.

Cameroon. South Region; Bipindi, Zenker G.A. 2980, Apr 1904: holotype: B[B10 0153055]; isotypes: BM[BM001125042]; BR [BR000008800398]; [BR000008800398]; G[G00308361]; GOET[GOET005676]; HBG[HBG-502538]; K[K000198949]; L[L.1754813]; M[M-0107910]; P[P00363341]; S[S03-2239]; WAG[WAG0053550] .

Description.

Liana, height unknown, d.b.h. unknown. Indumentum of simple hairs; old leafless branches glabrous, young foliate branches pubescent with short sericeous hairs. Leaves: petiole 3-4 mm long, 1-2 mm in diameter, sparsely pubescent to glabrous, grooved, blade inserted on the side of the petiole, 7.5-10 cm long, 4-5 cm wide, elliptic, apex acuminate, acumen ca.1 cm long, base obtuse, subcoriaceous, below sparsely pubescent to glabrous when young, glabrous when old, above glabrous when young and old, discolorous, whitish below (both when fresh and dry); midrib flat or sunken, above glabrous when young and old, below sparsely pubescent when young, glabrous when old; secondary veins 8 to 13 pairs, glabrous above; tertiary venation reticulate. Individuals bisexual; inflorescences cauliflorous or ramiflorous on young foliate branches, leaf-opposed or extra-axillary. Flowers with 9 perianth parts in 3 whorls, 1 per inflorescence; pedicel 18-22 mm long, ca. 1 mm in diameter, pubescent; in fruit 20-40 mm long, 2-3 mm in diameter, pubescent; bracts not seen; sepals 3, valvate, free, 1-2 mm long, 1-2 mm wide, triangular, apex acute, base truncate, pubescent outside, glabrous inside, margins flat; petals free, subequal; outer petals 3, valvate, 5-6 mm long, 3-4 mm wide, ovate, apex acute, base narrowed, margins flat, pubescent outside, pubescent inside; inner petals 3, valvate, 3-3.5 mm long, 2-3 mm wide, elliptic, apex obtuse, base truncate, margins flat, pubescent outside, pubescent inside; number of stamens not counted, number of rows not seen, 2-3 mm long, oblong; anthers not septate; connective discoid, pubescence not seen; staminodes absent; carpels not seen but free. Monocarps stipitate, stipes 5-10 mm long, 1-2 mm in diameter; monocarps 3 to 7, 10-15 mm long, 5-8 mm in diameter, ellipsoid, apex apiculate, pubescent, smooth, not ribbed, color unknown; seed 1, 13-15 mm long, 5-7 mm in diameter, ellipsoid; aril absent.

Distribution.

endemic to Cameroon; known from the South Region.

Habitat.

A rare species, in primary lowland rain forests. Altitude 100-200(?) m a.s.l.

Local and common names known in Cameroon.

None recorded.

IUCN conservation status.

NE (Not Evaluated), but probably CR.

Uses in Cameroon.

None recorded.

Notes.

Afroguatteria discostigma is only known from four collections by Zenker, all collected close to the type locality in Bipindi (South Region). It remains incompletely known and measurements here are incomplete. The species can be distinguished by its almost glabrous vegetative parts (young foliate branches and underside of young leaves can be pubescent with short hairs), its small leaves that are glaucous below (both when fresh and dry) and branches drying black. The flowers are borne on terminal pedicels that appear leaf-opposed or extra-axillary, but can also be cauliflorous (Zenker 3023), the carpels have a single ovule and thus monocarps are single-seeded like in Afroguatteria bequaertii (De Wild.) Boutique) ( Boutique 1951a). The altitude range given here is the one around Bipindi, but could be higher given that the mountain range Ngovayang (up to 1000 m) is very close.

A recent molecular phylogenetic study showed that this species (under the name Friesodielsia discostigma ) clustered in the genus Afroguatteria being sister to the Congolese species A. bequaertii ( Guo et al. 2017b). It is thus quite different genetically from the the African species of Friesodielsia (now Monanthotaxis ) in which it was placed before based on morphology ( van Steenis 1964).

Specimens examined.

South Region: Bipindi, 3.05°N, 10.25°E, 01 January 1905, Zenker G.A. 2102a (BM,BR,E,G,K,P); Bipindi, 3.05°N, 10.25°E, 01 January 1904, Zenker G.A. 3023 (BM,G,K,L,P,WAG); Bipindi, 3.08°N, 10.41°E, 01 March 1914, Zenker G.A. 576 (MA).

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 4. Afroguatteria discostigma A branch B upper and lower side of leaf, notice glaucous lower side and network like secondary veins C detail of upper lower side of leaf and petiole D inner (left) and outer petals (right), inner view E stamens front and side views F carpels side view and view of ovules G infructescence with moniliform monocarps A-C from Zenker 2980 [S 03 - 2239] reproduced from Swedish Museum of Natural History Department of Botany (S) https: // plants. jstor. org / D-G from Zenker 3023. Drawings by Helene Lamourdedieu, Publications Scientifiques du Museum national d'Histoire naturelle, Paris.