Faidherbia A. Chev., Rev. Bot. Appl. Agric. Trop. 14: 876. 1934.

Bruneau, Anne, de Queiroz, Luciano Paganucci, Ringelberg, Jens J., Borges, Leonardo M., Bortoluzzi, Roseli Lopes da Costa, Brown, Gillian K., Cardoso, Domingos B. O. S., Clark, Ruth P., Conceicao, Adilva de Souza, Cota, Matheus Martins Teixeira, Demeulenaere, Else, de Stefano, Rodrigo Duno, Ebinger, John E., Ferm, Julia, Fonseca-Cortes, Andres, Gagnon, Edeline, Grether, Rosaura, Guerra, Ethiene, Haston, Elspeth, Herendeen, Patrick S., Hernandez, Hector M., Hopkins, Helen C. F., Huamantupa-Chuquimaco, Isau, Hughes, Colin E., Ickert-Bond, Stefanie M., Iganci, Joao, Koenen, Erik J. M., Lewis, Gwilym P., de Lima, Haroldo Cavalcante, de Lima, Alexandre Gibau, Luckow, Melissa, Marazzi, Brigitte, Maslin, Bruce R., Morales, Matias, Morim, Marli Pires, Murphy, Daniel J., O'Donnell, Shawn A., Oliveira, Filipe Gomes, Oliveira, Ana Carla da Silva, Rando, Juliana Gastaldello, Ribeiro, Petala Gomes, Ribeiro, Carolina Lima, Santos, Felipe da Silva, Seigler, David S., da Silva, Guilherme Sousa, Simon, Marcelo F., Soares, Marcos Vinicius Batista & Terra, Vanessa, 2024, Advances in Legume Systematics 14. Classification of Caesalpinioideae. Part 2: Higher-level classification, PhytoKeys 240, pp. 1-552 : 1

Faidherbia A. Chev., Rev. Bot. Appl. Agric. Trop. 14: 876. 1934.

Figs 204 , 205 , 208

Type.

Faidherbia albida (Dalile) A. Chev. [≡ Acacia albida Dalile]

Description.

Trees to 30 m, with trunks up to 2 m diameter, the spreading branches forming a rounded crown, armed with spinescent stipules. Stipules spinescent, paired, persistent, straight or slightly curved, to 2 (3.3) cm long. Leaves bipinnate, cup-shaped extrafloral nectaries on the leaf rachis at the junction of each pair of pinnae, absent on the petiole; pinnae (2) 3-10 pairs; leaflets 6-23 pairs per pinna, opposite, small (3.5-9 mm long), linear or linear-oblong to slightly obovate-oblong. Inflorescences spicate, pedunculate, solitary, arising from leaf axils, collectively forming a terminal pseudopanicle. Flowers hermaphrodite; calyx cup-shaped, 5-lobed; corolla campanulate, pale pink inside, the 5 lobes divided almost to the base; stamens 35-55, long exserted from the corolla, with the base fused for ± 1 mm forming a short tube, yellowish-white to pale cream, anthers eglandular; pollen organised in 32-grained polyads, these acalymmate, subcircular, flattened; ovary short-stipitate. Fruits thick, flattened, falcate or conspicuously curled and twisted, bright orange when mature, indehiscent. Seeds elliptic-lenticular, compressed, with an elliptic pleurogram.

Chromosome number.

2 n = 26 ( Goldblatt 1981b; Bukhari 1997).

Included species and geographic distribution.

Monospecific ( F. albida ), widespread in Africa, especially across eastern Africa, from Egypt southwards into Sudan, Ethiopia, Somalia, Kenya, Uganda, Tanzania, Mozambique, Zambia and Zimbabwe, to the Transvaal, South Africa. Also reported from Mauritania, Senegal and The Gambia, and in Angola southwards to Botswana (Fig. 208 ). Also occurring in parts of the Middle East and Arabia, and probably introduced in west Asia (India and Pakistan).

Ecology.

Found predominantly in seasonally dry tropical climates, in forests, woodlands and especially in savannas where it is often abundant, on alluvial soils, along seasonal watercourses and around lakes and swamps, from near sea level to 2600 m elevation. It shows an unusual reverse phenology being characteristically leafless during the rainy season. Faidherbia albida is reported to have a rather generalist reproductive system ( Gassama-Dia et al. 2003). Pollination is both entomophilous and anemophilous, and predominantly allogamous; individuals are primarily self-incompatible, although partially self-compatible genotypes exist. The ripe indehiscent fruits are eagerly consumed by large herbivores including livestock facilitating extensive endozoochorous seed dispersal ( Barnes and Fagg 2003).

Etymology.

Named after the French Major Louis Léon César Faidherbe (1818-1889), Governor of Senegal and founder of Dakar.

Human uses.

The trunks are used to make canoes, and the wood is employed as firewood, and for handicrafts; various medicinal uses are reported. The leaves and fruits are used as fodder for domestic animals, and are also consumed by camels and elephants ( Barnes and Fagg 2003).

Notes.

Originally described as Acacia albida Dalile, this species has several unusual characters as compared with the other African species of Acacia Mill., such as the lack of petiolar extrafloral nectaries, these being present only at the junction of each pair of pinnae, the basally connate filaments forming a short tube (in line with most members of the ingoid clade and all members of the Zapoteca clade), the eglandular anthers, and the 32-grained polyads ( Kordofani and Ingrouille 1992). This combination of morphological characters places F. albida apart from the African Vachellia and Senegalia .

Taxonomic references.

Brenan (1959, 1970).

Figures

Figure 204. Morphological features of the Zapoteca clade A, B Faidherbia albida (Delile) A. Chev. A habit B leaves C, D Sanjappa Calliandra cynometroides (Bedd.) E. R. Souza & M. V. Krishnaraj C habit D pinnate leaves and inflorescence in bud E Zapoteca aculeata (Spruce ex Benth.) H. M. Hern. foliage and inflorescences at anthesis (Neill 18437) F Zapoteca formosa subsp. schottii (Torr. ex S. Watson) H. M. Hern. habit and dehisced fruits G Viguieranthus glaber Villiers leaves and inflorescences post-anthesis. Photo credits A Gobabeb - Namib Research Institute B Dave U C, D G Suresh E D Neill F D Beckman G C Davidson.

Figure 205. Inflorescence and fruit morphology in the Zapoteca clade A, B Faidherbia albida (Delile) A. Chev. A inflorescences at anthesis B indehiscent fruit C, D Sanjappa Calliandra cynometroides (Bedd.) E. R. Souza & M. V. Krishnaraj C inflorescence post-anthesis D pinnate leaves and immature fruit E Thailentadopsis tenuis (Craib) Kosterm. inflorescence F Viguieranthus perrieri (R. Vig.) Villiers inflorescence at anthesis G Viguieranthus alternans (Benth.) Villiers foliage and fruits before dehiscence H Viguieranthus brevipennatus Villiers inflorescence at anthesis (Randrianarivony 175) I Zapoteca tetragona (Willd.) H. M. Hern. inflorescence at anthesis J Zapoteca portoricencis (Jacq.) H. M. Hern. subsp. portoricensis inflorescence at anthesis (Amith 74438) K Zapoteca formosa subsp. schottii (Torr. ex S. Watson) H. M. Hern. dehisced fruit. Photo credits A S Piry B B Adkins C, D G Suresh E https: // marketingoemoffice. com / Data _ Pithecellobium. html F F Ratovoson G F Rakotoarivony H T Randrianarivony I FJ Gomez Marin J J Amith K D Beckman.

Figure 208. Distribution of Faidherbia based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.