Cleistopholis myristiciflora Diels & Mildbr., Bot. Jahrb. Syst. 53(3-5): 439 (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 : 89-91

Cleistopholis myristiciflora Diels & Mildbr., Bot. Jahrb. Syst. 53(3-5): 439 (1915)

Map 3D

Type.

Cameroon. South Region (?) or Equatorial Guinea. Río Muni; Campo-Gebiet; Bebao [i?], Weg nach Olonga [Manga?], Tessmann, G. 767, 6 Jan. 1909: holotype: B[B 10 0154074] .

Description.

Tree, to 19 m tall, d.b.h. to 16 cm; stilt roots or buttresses absent, trunk brown. Indumentum of simple hairs (?); old leafless branches glabrous, young foliate branches pubescent (?). Leaves: petiole ca. 3 mm long, ca. 1 mm in diameter, pubescent (?), grooved, blade inserted on the side of the petiole; blade 8-12 cm long, ca. 4 cm wide, elliptic to oblong, apex acuminate, acumen ca. 1.5 cm long, base cuneate, papyraceous, below pubescent when young (?), glabrous when old, above glabrous when young and old, concolorous; midrib impressed, above glabrous when young and old, below pubescent when young (?), glabrous when old; secondary veins 10 to 13 pairs, glabrous below; tertiary venation reticulate. Individuals bisexual; inflorescences ramiflorous on young and old leafless branches, axillary, peduncule generally absent. Flowers with 9 perianth parts in 3 whorls, 4 to 9 per inflorescence, pedicel 15-27 mm long, ca. 1 mm in diameter, sparsely pubescent (?); in fruit ca. 20 mm long, 2-3 mm in diameter, glabrous (?); bracts not seen (soon falling?); sepals 3, valvate, free, 1.5-2 mm long, ca. 1.5 mm wide, circular, apex rounded, base rounded, color unknown, pubescence not observed, margins flat; petals free; outer petals 3, valvate, 5-7 mm long, 2-3 mm wide, broadly elliptic to oblong, apex rounded, base truncate, color unknown, margins flat or wavy when dry, pubescence not observed; inner petals 3, imbricate (?), dimensions and shape not observed; stamens number not counted, row number not counted, ca. 1 mm long, broad; connective discoid, pubescence not observed, color unknown; staminodes absent (?); carpels free, 10 to 15 (?, possibly more based on the number of monocarps counted), ovary ca. 1.5 mm long, stigma flat, glabrous. Monocarps stipitate, stipes 49-50 mm long, ca. 1 mm in diameter; monocarps 17 to 18, 10-15 mm long, 10-15 mm in diameter, globose, apex rounded, glabrous (?), bumpy; seeds not seen.

Distribution.

Equatorial Guinea and Cameroon (?); if present in Cameroon then from South region.

Habitat.

A rare species, in primary submontane tierra firme forest. Altitude 750-850 m a.s.l. (altitude in Equatorial Guinea).

Local and common names known in Cameroon.

Akom (Equatorial Guinea) ( Guinea López 1946).

IUCN conservation status.

No assessed, but probably CR.

Uses in Cameroon.

None recorded.

Notes.

Cleistopholis myristiciflora (initially known only from the type; Tessmann 767 (B, but see below)) was originally described as being from Cameroon ( Diels 1915) with the type locality written as "Kamerun: Campo-Gebiet; Bebao[i?], Weg nach Olonga [Manga?]". This locality information, however, is also found on several other of Günther Tessmann (1884-1969) specimens (e.g. 779, 800), collected between end 1908 and early 1909 but are suggested to be from Equatorial Guinea rather than Cameroon. Tessmann is suggested to have collected around 700 specimens in Equatorial Guinea between the island of Bioko and mainland Río Muni ( Fero 2013). Le Thomas (1969b) also suggested this species is from Equatorial Guinea and is cited in the check list of plants in "Ensayo geobotánico de la Guinea continental Española” ( Guinea López 1946). It was however not cited in the "Les arbres de la Guinée Équatoriale” ( Wilks et al. 2000). Fero indicates that they did not locate any specimens of this species in Equatorial Guinea in the herbaria of BATA, LISU, MA and WAG, but suggest it should be present ( Fero 2013). In Tessmann’s book about the Pangwe culture ( Tessmann 1913), the name "Bebai “Bébai” is found several times and is suggested to be at the border between Equatorial Guinea and Cameroon (page XXI). There is a map in the book (page 1) showing a village named Bébai, almost exactly on the border between Equatorial Guinea and Cameroon. Thus, evidence for its presence in Cameroon is still doubtful with no recent collections in Cameroon but two recent ones from Equatorial Guinea (see below). We include it in our taxonomic treatment as tentatively occurring in Cameroon and provide a tentative coordinate for Bebai in the map of this species.

The taxonomic affinities of this species were unclear for some time but suggested to be conspecific with either C. patens or C. staudtii . Le Thomas (1969b) notes that it has morphological characters of both C. patens (shape of the petals and number of carpels) and C. staudtii (leaf shape and venation), the later also suggested by Diels and Mildbrand (1915).

Recently, we located two specimens collected from Monte Alén in Guinea Equatorial (Senterre & Obiang 2939, 3699, BRLU) which appear to belong to C. myristicifolia (identified as such by B. Senterre). The leaves match the description and the type specimen, especially the shape and the length of the petiole being shorter (ca. 3 mm) than in the other species (> 3 mm). One specimen (Senterre & Obiang 2939), is in fruit. This single fruit is morphologically quite different than those of the other species in Cleistopholis . It is partially described here for the first time. The main difference is the length and diameter of the stipes being much longer and thinner than those from the other three species (49-50 mm long and ca. 1 mm in diameter versus 1-30 mm and 2-3 m in diameter). The number of monocarps appears to be higher with 17 to 18 counted in Senterre & Obiang 2939, versus 3 to 8 in the other species. These observations strongly support the hypothesis that C. myristiciflora is indeed a distinct and valid species. In terms of its ecology, observations from Senterre & Obiang suggest it to occur in primary submontane rain forests, occurring on gentle slopes or top of small mountains.

One specimen collected from southern coastal Gabon (Bergen 217 [WAG.1379499, WAG.1379500]) at 10 m a.s.l. was identified as C. myristiciflora by M. Fero. It is true that the inflorescences and flowers could potentially match, but the size of the tree (8 m) and leaves are different having a long petiole (> 3 mm). The ecology is also different than described above occurring along the coast on laterite soil. For now we do not consider this specimen as part of C. myristiciflora and Bergen 217 could potentially represent an undescribed Gabonese coastal species, as has been done recently in other Annonaceae genera such as Greenwayodendron littorale Lissambou, Dauby & Couvreur ( Lissambou et al. 2018).

Figures

Map 3. A Artabotrys velutinus B Brieya fasciculata C Cleistopholis glauca D Cleistopholis myristiciflora E Cleistopholis patens F Cleistopholis staudtii G Dennettia tripetala H Duguetia barteri I Duguetia confinis. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).