Isolona campanulata
Tree or shrub to 10(-15) m tall; d.b.h. to 10(-15) cm, frequently narrowly fluted to base of crown; bark dark brown; young branches dark green, drying black, glabrous; old branches light brown drying brown to black, glabrous, striate. Petioles 3-4(-6) mm long, 1-1.5 mm in diameter, glabrous, grooved adaxially, leaf lamina inserted on side. Leaf lamina 10-15(-18) cm long, 3-7 cm wide, length:width ratio 2.2-3.9, narrowly elliptic to elliptic or narrowly obovate to obovate, subcoriaceous to papyraceous, glabrous on both sides, dark green above, light green below, sometimes with black glands, base decurrent to narrowly cuneate, apex acuminate, acumen ca. 1 cm long; midrib raised and glabrous adaxially, prominent and glabrous abaxially; secondary veins 7-12 pairs, glabrous on both sides. Inflorescences sometimes with 1(-2) additional rhipidia, on leafy branches. Flowering pedicels (5-)12-30(-35) mm long, ca. 0.5 mm in diameter; lower bracts 1-4, 2-3 mm long, 1-2 mm wide, upper bract sub-basal to halfway up pedicel, sometimes leaf-like, 2-19 mm long, 1-4 mm wide, sessile to petiolate, petiole 1-2 mm long, base cuneate, apex rounded, papyraceous, glabrous. Sepals 4-9 mm long, 3-5 mm wide, length:width ratio 1-3, broadly ovate to elliptic, papyraceous, glabrous, persistent on young fruits, base truncate, apex acute; margins glabrous. Corolla green when immature turning bright yellow at anthesis; tube 9-20 mm long, 4-5 mm in diameter, lobe:tube ratio 1-2; lobes 6-20 mm long, 2-7 mm wide, length:width ratio 2-5, triangular to narrowly triangular, apex acute, glabrous, papyraceous. Receptacle ca. 4 mm in diameter. Stamens ca. 1.2 mm long; connective shields ca. 0.1 mm long, glabrous, those of innermost stamens extended over adjacent ovary wall. Ovary ca. 2 mm long, ca. 2 mm in diameter; stigma ca. 1 mm in diameter, capitate, glabrous. Fruiting pedicels 2-5 cm long, 2-3 mm in diameter, glabrous. Fruits 4-7.5 cm long, 2-3.5 cm in diameter, length:width ratio 1.5-3, narrowly ovoid to ovoid, not apiculate, smooth with lumpy aspect on fresh and dried material, green turning deep yellow when mature; pericarp ca. 1 mm thick. Seeds 8-15 mm long, 5-10 mm in diameter, ellipsoid to transversely ellipsoid, packed in white pulp; testa rugose, dark brown, raphe thickened; hilum 5-6 mm long, 1-1.5 mm wide, narrowly elliptical.
Isolona campanulata can be distinguished by its fairly large, foliaceous and glabrous sepals not appressed against the tube, as well as the sometimes leaf-like upper bract. The flowers are campanulate with the corolla lobes acute at the apex. The flower shape suggests a close affinity with I. deightonii (not sampled in the molecular study), but the latter species is distinct by the presence of short curly and reddish hairs on young and old branches as well as on the flowers. Isolona campanulata also presents a close affitinity with I. cooperi by the shape of the corolla lobes and the fruit, a relationship also strongly supported by molecular data (Fig. 1). However, I. cooperi is distinct by the leaf lamina inserted on top of the petiole, the presence of a strong sweet scent, and smaller sepals appressed against the corolla tube.
A root decoction is drunk in Sierra Leone against rheumatism (Irvine 1961). In Ivory Coast it is used for bronchial troubles, to allay fever, and against worms (Irvine 1961). A powder made from the bark is used as an aphrodisiac (Irvine 1961).
LC. Isolona campanulata is well represented in herbaria from both West and Central Africa. It occurs in several protected areas such as national parks (Banco and Tai in Ivory Coast, Korup in Cameroon) as well as in forest reserves (Ankasa, Bonsa Ben and Subri River in Ghana; Angédédou and Banco in Ivory Coast; Kienke in Cameroon). Furthermore, it has been collected frequently in recent years, which is why the category of “least concern” is applied here.
Isolona campanulata is sister to Isolona cooperi.
Disjunct, from Sierra Leone to Ghana and in south-eastern Nigeria, western Cameroon and one specimen collected in Gabon; in primary and secondary rain forest, and along rivers; at 0-500 m altitude.