Raphia hookeri G. Mann & H. Wendl.

Raphia hookeri G. Mann & H. Wendl. (Mann and Wendland 1864: 24: 438) Figs 10, 11 Description. Palms 6–8 m high, gregarious with several individuals forming a monodominant stand. Stipes solitary, rarely appearing clustered, fully covered with fibres forming dense springs; fibres at least 8 mm wide. Leaves 5.65–10.5 m long. Petiole 1.81–3.80 m long, not spiny, channeled on the upper side (that facing the stipe); DP 30 comprised between 2.9–5.6 cm. Rachis 3.60–7.92 m long; channeled on the upper side, spiny on each side of the cleft. Leaflets 85–172 × 2.6–5.8 cm; 6–27 in the R 0–30 area of the rachis, with spines in two rows on the midrib and with marginal spines. Inflorescences (3 –) 4–5 per individual, 1.6–1.9 m long (including a peduncle of c. 30 cm) and 57–86 cm wide. Partial inflorescences 40–60 cm long and 20–35 cm wide. Second order rachillae up to 17–34 cm long and 8 mm wide. Infructescence hanging. Fruits ellipsoid to oblong, 4.4–8.2 (– 10.6) × 3.1–4.9 cm, green when immature and yellow to reddish when mature, with a 1–1.5 (– 1.8) cm long beak. Ecology. Forming monodominant stands (‘ raphiales’) stretching in some cases for more than 10 km, often along rivers, and planted in villages. In Republic of the Congo, it flowers in August, fruits present in May, August, September, October. Distribution. Angola (Cabinda), Benin, Cameroon, Central African Republic, Côte d’Ivoire, Democratic Republic of the Congo, Equatorial Guinea, Gabon, Gambia, Ghana, Guinea, Liberia, Nigeria, Republic of the Congo, Sierra Leone, Togo (Brink and Achigan-Dako 2012; Couvreur and Sunderland 2022; Harris 2002; Mogue Kamga et al. 2019); in the Republic of the Congo, the species occurs in Brazzaville, Likouala, Cuvette, Cuvette-Ouest, Kouilou, and Niari. IUCN conservation assessment. Raphia hookeri was assessed by Cosiaux et al. (2018 b) as Least Concern (LC). Uses. The sap is tapped and used as Raphia wine called Molengue in Lingala; Péké in Mbenzele (Likouala); Mali ouliè in Téké (Lékana, Plateaux); Ouliè in Téké (Kébouya, Cuvette-Ouest); Olènguè in Mbochi (Cuvette); Ntombé in Ndzabi (Lesoka camp, Niari). The rachis, with the leaflets still attached, are grouped in 5 or 6 to cover the roofs of huts (Moumbelou, Likouala). The young leaflets are also used as cassava wrappers (Tchikapika, Cuvette). The pulp of the fruit is used to make the red oil known as “ Kolo ” in Mbochi (Silou et al. 2000). In Cuvette and Plateaux departments, the pulp is fermented for a few days in water after cooking, called “ pandé ” in Mbochi, and is eaten. The name “ pandé ” in Mbochi is also used for the same product from R. laurentii. According to Limingui et al. (2021), the fermented pulp has medicinal properties and contains proteins, fats, and sugars. The pith (inert and soft part) of young stipes called “ Otowa ” in Mbochi (Tchikapika and Oyo; Cuvette) can be eaten raw or cooked. People harvest the edible larvae of Oryctes sp. Hellwig, 1798 (Coleoptera, Scarabaeidae) from the dead and decayed stipe. These larvae are called “ Aboh ” (sing. Iboh) in Mbochi (Tchikapika and Oyo; Cuvette) and are sold in markets. Vernacular names. Péké in Makao (Cuvette); Péké in Mbenzele (Likouala); Ouliè, plural Iliè, in Téké (Plateaux); Olènguè, plural Elènguè, in Téké (Cuvette-Ouest), plural Ilènguè, in Mbochi (Cuvette); Bongo, plural Abongo, in Makoua (Cuvette); Ntombé in Ndzabi (Niari); Dirombi, plural Marombi, in Punu (Niari); Tohombi in Vili (Kouilou). Notes. Raphia species sharing the curling fibres pattern form the section Temulentae Otedoh which contained three species R. hookeri, R. rostrata, and R. sese De Wild. (Otedoh 1982; Tuley 1995) but now has four species with the addition of R. gabonica (Helmstetter et al. 2020). From our work, we found that R. hookeri can be distinguished from R. rostrata by having the fibres which form tightly coiled springs which cover the stipe whilst in R. rostrata the fibres are pendant and do not form tightly coiled springs. In addition, the petiole of R. hookeri has a smaller diameter, DP 30 size is 2.9–5.6 cm, whereas the petiole is broader in R. rostrata which has a DP 30 size of 6.7–7.7 cm. Fruits are ellipsoid to oblong with a 10–15 (– 18) mm long beak in R. hookeri whereas they are oblong to cylindrical, rarely ellipsoid; reddish, with a 8–9 mm long beak in R. rostrata. Raphia hookeri resembles R. sese (not treated in this paper) by having yellow fruits in addition to the presence of the same type of fibres on the stipe. The latter species can be recognized by its fruits generally ovoid, obovoid to ellipsoid, orange to yellowish brown with a 10–18 mm beak length (Mbandu Luzolawo et al. 2020; Tuley 1995). The field observations that we made on the fruits of R. hookeri show an overlap in the size of the beak with reported values for R. sese. Such an overlap in fruits traits can lead to confusion in the identification of the two Raphia species. This is the case for the work by Silou et al. (2000) which was carried out on the oil called “ Kolo ” from R. sese. We believe that the species used in that study is probably R. hookeri, as “ Kolo ” is the Mbochi name given to the oil of R. hookeri in the Northern part of the Republic of the Congo where we collected herbarium specimens and where the oil is produced. These two observations indicate that more collections and observations should be made in the field to better understand these two taxa and find out if R. sese also occurs in the Republic of the Congo. R. hookeri also resembles R. gabonica (not treated in this paper) but the latter has fruits being globose, deltoid or ovoid; orange-red fruits, with a 5 mm long beak long and grows on tierre firme and near streams and does not form monodominant stands (Kamga et al. 2018). Specimens examined. Republic of the Congo. • Brazzaville. Mfilou, 04°11.26'S, 015°17.35'E, 372 m, 17 May 2019, Ndolo Ebika 2699 (HICPC); • Cuvette. Makoua, 00°00.10'N, 015°36.54'E, 327 m, 21 Aug 2019, Ndolo Ebika 2729 (HICPC); • Cuvette-Ouest. Kébouya, 01°08.65'S, 014°56.79'E, 394 m, 17 Aug 2019, Ndolo Ebika 2709 (HICPC); • Kouilou. Bas-Kouilou, 2 km NW of the bridge on the Kouilou River, West of the Bas-Kouilou village at c. 100 m away from the main road, 04°27.53'S, 011°42.30'E, 10 m, 28 Sep. 2019, Ndolo Ebika & Harris 2742 (HICPC, E); • Likouala. Epena, 01°20.86'N, 017°26.23'E, 340 m, 07 Mar 2024, Ndolo Ebika s. n. [photo only] (HICPC); Moumbelou, 02°24.32'N, 017°31.87'E, 341 m, 14 Aug 2018, Ndolo Ebika s. n. [photo only] (HICPC); • Niari. Lesoka camp, close to Mafoubou River, about 9 km N of Dolisie, 04°08.10'S, 012°42.13'E, 320 m, 5 Oct 2019, Ndolo Ebika & Harris 2763 (HICPC, E); • Plateaux. Lékana, 02°18.97'S, 014°32.20'E, 798 m, 14 Aug 2019, Ndolo Ebika 2707 (HICPC).