Isolona campanulata Engl. & Diels, Monogr. Afrik. Pflanzen.-Fam. 6: 83, 1901

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 : 131-133

Isolona campanulata Engl. & Diels, Monogr. Afrik. Pflanzen.-Fam. 6: 83, 1901

Fig. 33 ; Map 4I

= Isolona leonensis Sprague & Hutch., Bull. Misc. Inform. Kew: 151, 1916. Type. Sierra Leone. Northern Province, Yonibana, Thomas N.W. 4230, 30 Oct 1914: lectotype, designated by Couvreur (2009), p. 137: K[K000199016]. (this name was erroneously reported as " I. konensis " in Onana (2011)).

= Isolona soubreana A.Chev., Explor. Bot. Afrique Occ. Franc. 1: 12, 1920. Type. Ivory Coast. Sassandra, Chevalier A.J.B. 19088, 23 Jun 1907: lectotype, designated by Couvreur (2009), p. 137, sheet here designated: P[P00363265]; isolectotypes: P[P00363264, P00363266]; WAG[WAG0027026].

Type.

Cameroon. Northern Region ; Bangwe, Conrau G. 93, 17 Oct 1899: holotype: B[B 10 0154200]; isotype: K[K000198841] .

Description.

Tree to shrub, 10-15 m tall, d.b.h. 10-15 cm; stilt roots or buttresses absent. Indumentum absent; old leafless branches glabrous, young foliate branches glabrous. Leaves: petiole 3-6 mm long, 1-2 mm in diameter, glabrous, weakly grooved adaxially, blade inserted on the side of the petiole; blade 10-18 cm long, 3-7 cm wide, elliptic to obovate, apex acuminate, acumen 1 cm long, base decurrent to cuneate, subcoriaceous, below glabrous when young and old, above glabrous when young and old, concolorous; midrib raised, above glabrous when young and old, below glabrous when young and old; secondary veins 7 to 12 pairs, glabrous below; tertiary venation reticulate. Individuals bisexual; inflorescences ramiflorous on old or young foliate branches, axillary. Flowers with 9 perianth parts in 2 whorls, 1 to 2 per inflorescence; pedicel 5-30 mm long, ca. 1 mm in diameter, glabrous; in fruit 2-5 mm long, 2-3 mm in diameter, glabrous; bracts 2 to 5, several basal and one upper towards the lower half of pedicel, basal bracts 2-3 mm long, 1-2 mm wide; upper bract sometimes leaf-like, 2-19 mm long, 1-4 mm wide; sepals 3, valvate, free, 4-9 mm long, 3-5 mm wide, elliptic to ovate, apex acute, base truncate, green speckled with red and purple, glabrous inside, glabrous outside, margins flat; petals basally fused, tube 4-7 mm long, inner and outer whorl not differentiated, equal; lobes 6-20 mm long, 2-7 mm wide, triangular, apex acute, green, turning bright yellow, margins flat, glabrous outside, glabrous inside, spreading horizontally; stamens numerous, in 3 to 4 rows, ca. 1 mm long, broad; connective discoid, glabrous, cream; staminodes absent; carpels fused into a single structure, ca. 2 mm long, stigma capitate, glabrous. Fruit syncarpous, sessile, 40-75 mm long, 20-35 mm in diameter, ovoid, apex rounded, glabrous, smooth, bumpy, green turning deep yellow when ripe; seeds not counted, 8-15 mm long, 5-10 mm in diameter, ellipsoid; aril absent.

Distribution.

A widespread species with a disjunct distribution in West (Sierra Leone, Liberia, Ivory Coast and Ghana) and Central Africa (Cameroon, Gabon); in Cameroon known from South, Central, Littoral and South-West regions.

Habitat.

An infrequent species in Cameroon; in lowland primary and secondary forests, also along rivers. Altitude 0-500 m a.s.l.

Local and common names known in Cameroon.

None recorded.

IUCN conservation status.

Least Concern (LC) ( Cosiaux et al. 2019p).

Uses in Cameroon.

medicine: root against rheumatism, allay fever.

Notes.

This species is characterized by its large, foliaceous, and glabrous sepals, not appressed against the corolla tube, as well as the sometimes leaf-like upper bract. It is also a completely glabrous species, a character only shared with I. cooperi and I. hexaloba . The flower of I. campanulata is very distinct and uniquely campanulate.

Specimens examined.

Littoral Region: Lombe amp Tissongo Study Area Doula-Edea Reserve , 3.78°N, 10.04°E, 01 June 1976, Waterman P.G. 830 (K). South Region : ca 15 km SE of Kribi Kienke Forest Res at Bidou II, 2.86°N, 10.03°E, 30 June 1969, Bos J.J. 4947 (BR,P,WAG,YA); 10 km From Kribi Lolodorf road, 2.96°N, 9.966°E, 09 July 1970, Bos J.J. 7069 (WAG). South-West Region : 5.46°N, 9.883°E, 7 October 1899, Conrau G. 93 (B,K); 16 minutes from research station towards rivers, 5.34°N, 9.496°E, 27 November 2000, Gosline W.G. 289 (K); Ente Ekondo Nene et Loe 15 km NW Ekondo Titi, 4.69°N, 8.97°E, 03 June 1976, Letouzey R. 15078 (P,YA); Korup National Park , 5.31°N, 8.966°E, 02 July 1951, Olorunfemi J. 30662 (K); Korup National Park between the Ndian River at PAMOL field and 25 km on transect " P ", 5.01°N, 8.833°E, 12 April 1985, Thomas D.W. 4763 (BR,K,MO,P,WAG,YA); Takamanda Forest Reserve, 6.21°N, 9.433°E, 30 April 1987, Thomas D.W. 7354 (MO,P,WAG) .

Figures

Map 4. A Duguetia dilabens B Duguetia staudtii C Greenwayodendron glabrum D Greenwayodendron suaveolens E Hexalobus bussei F Hexalobus crispiflorus G Hexalobus monopetalus H Hexalobus salicifolius I Isolona campanulata. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).

Figure 33. Isolona campanulata A flower, side view B flower, top view. Isolona congolana C flowering branch D base of leaf blade, top view E flower, top view F flower, bottom view G syncarpous fruit A, B no voucher, Bayang Mbo, Cameroon C-G Couvreur 1054, Mt Cameroon. Photos A, B Sonneck C-G Thomas L. P. Couvreur.