Raphia gentiliana De Wild. (De Wildeman 1905: 29)

Figs 8, 9

Description.

Palms 6 to 10 m high, 16 cm in diameter, isolated or gregarious and forming in the latter case small mono-dominant stands of up to 17 individuals within a radius of 50 m. Stipes solitary, with two types of fibres: the narrower, rounded fibres 2–3 mm in diameter that run around the stipe and the flattened fibres, curling and hanging, forming belt-like ribbons up to 4.5 cm wide breaking down to form smooth fibres 5–6 mm. Leaves 7.60–10.58 m long. Petiole laterally fluted from base to rachis, unarmed, 3.72–4.10 m long; DP 30 comprises between 4.7–7.7 cm. Rachis 6.18–6.86 m long, laterally fluted, with a row of spines on each side of the cleft. Base of rachis uneven, with an offset of 12 to 27.5 cm between the two groups of basal leaflets on either side. Basal leaflets, on both sides of the rachis, grouped into a tuft of 4–8 leaflets, 1.33–1.41 m × 8.0– 8.4 cm, 12–35 in the R 0-30 area of the rachis, with dorsal spines (on the main vein) 5 mm long and marginal spines 4 mm long. Inflorescences: when young, 5–6 per individual, hanging, very tapered, approx. 2 m long; when mature 3.1 m (including peduncle 70 cm) long and 50–60 cm wide. Partial inflorescence 60 × 35 cm. Secondary and final branches 45 cm long. Infructescence hanging, 3.80 m long. Fruits ellipsoid to almost cylindrical, 4.8–7 × 2.5–5.5 cm, dark green when immature, becoming brownish and reddish when mature, rounded at the top with a 5 mm long beak.

Ecology.

Mainly growing on tierra firme in secondary forest, in light gaps, old fields, edge of roads, and swamps, planted in villages. It flowers in February, August, and October, and fruits in May, August, and October.

Distribution.

Angola, Central African Republic, and Democratic Republic of the Congo (Mbandu Luzolawo et al. 2020), Republic of the Congo (this study); in the Republic of the Congo, the species occurs in Brazzaville, Cuvette, Cuvette-Ouest, Lékoumou, Likouala, and Plateaux.

IUCN conservation assessment.

Raphia gentiliana has been assessed as Least Concern (LC) by Cosiaux et al. (2018 a) who recommend further studies to better understand the area of occupancy of the species.

Uses.

The epidermis of the young leaflets of Raphia gentiliana is used to make traditional dance skirts in Moumbelou and Bonguinda (Likouala). The sap is tapped and used to make Raphia wine called Pigui in Ingoumina (Lékoumou). The petiole is used as laths to make the framework of huts, the skeleton of hut walls, and to make the two sticks that make up the skeleton of roofing tiles. In Kébouya (Cuvette-Ouest), the palm tree is felled, wounded at several points, and left to decay in order to harvest the edible larvae of Rhynchophorus cf. phoenicis.

Vernacular names.

Pigui, Pih-ongoungouma in Téké (Cuvette-Ouest); Opeou in Makoua, (Cuvette); Pigui in Téké (Lékoumou); Pòndo or Dihondò in Mbenzele (Likouala).

Notes.

Raphia gentiliana resembles R. textilis in the palm growth habit and the use of the epidermis of the young leaflets. We found that the easiest character to distinguish the two species is the fruit shape. Fruits are ellipsoid with a rounded to cuneate apex in R. gentiliana, while globose with a truncate apex in R. textilis. Tuley (1995) described the fruits as variable in shape, tapering club shaped to more globose or ellipsoid / ovoid for R. gentiliana, turbinate and sometimes near cylindrical in shape for R. textilis. Mbandu Luzolawo et al. (2020) reported the use of the epidermis of the young leaflets of R. gentiliana in the Democratic Republic of the Congo whereas Mogue Kamga et al. (2019) reported a similar use for R. textilis in Gabon. Further investigations in the field are needed for a better understanding of the two species.

Specimens examined.

Republic of the Congo. • Brazzaville. Saint Denis, 04°06.41'S, 015°12.78'E, 332 m, 27 Oct 2018, Ndolo Ebika 2458 (HICPC); Mfilou, 04°11.26'S, 015°17.35'E, 372 m, 17 May 2019, Ndolo Ebika 2698 (HICPC); • Cuvette. Makoua, 00°00.0'N, 015°36.13'E, 338 m, 22 Aug 2019, Ndolo Ebika 2734, (HICPC); • Cuvette-Ouest. Kébouya, 01°08.65'S, 014°56.79'E, 394 m, 17 Aug 2019 Ndolo Ebika 2710 (HICPC); 01°08.75'S, 014°56.62'E, 425 m, 18 Aug 2019, Ndolo Ebika 2726 (HICPC); Ndjoukou. 00°12.58'N, 014°10.56'E, 539 m, 16 Feb 2020, Ndolo Ebika 3079 (HICPC); • Lékoumou. Ingoumina, 7 km from Zanaga on the road to Sibiti and 1.7 km E from the village Ingoumina, 02°53.48'S, 013°51.81'E, 570 m, 1 Oct 2019, Ndolo Ebika & Harris 2754 (HICPC, E); 7 km from Zanaga on the road to Sibiti, 02°52.51'S, 013°50.06'E, 540 m, 1 Oct 2019, Ndolo Ebika & Harris 2758 (HICPC, E); • Likouala. Moumbelou, 02°24.40'N, 017°32.04'E, 345 m, 15 Aug 2018, Ndolo Ebika s. n. [photo only] (HICPC).