Piptadeniastrum Brenan, Kew Bull. 10: 179. 1955.

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

Piptadeniastrum Brenan, Kew Bull. 10: 179. 1955.

Figs 120 , 121 , 122 , 125

Type.

Piptadeniastrum africanum (Hook. f.) Brenan [≡ Piptadenia africana Hook. f.]

Description.

Tall trees, unarmed, with ramified, aliform buttresses often more than 3 m high (Fig. 120H, I ). Stipules linear, densely pubescent, 5.5-9 mm long, apex sharp, caducous. Leaves (Fig. 121F ) bipinnate, eglandular; pinnae often alternate, 10-19 (23) pairs per leaf; leaflets (26) 30-58 (61) pairs per pinna, sessile, linear or falcate, apex obtuse, base asymmetric. Inflorescence (Fig. 121I, J ) a panicle of fascicled spiciform racemes, terminal. Flowers (Fig. 121I ) pedicellate with abscission zone near pedicel apex, bisexual, yellow or yellowish-white; calyx gamosepalous, cupuliform, distinctly toothed; petals free, glabrous, adnate basally with the stamens and a perigynous disc forming a stemonozone; stamens 10, filaments red, anther connective terminating in a large globular, sessile, caducous gland; pollen tricolporate, finely reticulate, dispersed as monads; ovary glabrous, red, ovules 9, style slender, stigma porate and slightly dilated. Fruit (Fig. 122K ) flattened, straight to slightly curved, dehiscent along a single suture, the valves remaining attached along the other, exocarp coriaceous. Seeds (Fig. 122L ) flattened, surrounded by a broad membranous wing, oblong, funicle inserted near the middle of a long margin.

Chromosome number.

2 n = 26, diploid ( Lewis and Elias 1981; Santos et al. 2012).

Included species and geographic distribution.

One species, P. africanum , in tropical Africa, from Liberia and Guinea east to South Sudan and Uganda, and south to Angola (Fig. 125 ).

Ecology.

Rainforest and in riparian vegetation within more seasonally dry tropical forest.

Human uses.

Used for commercial timber, charcoal, fish and rodent poison, in traditional medicines and in rituals ( Luckow 2005).

Notes.

In his revision of the African members of Piptadenia (sensu Baker 1930), Brenan (1955) created the segregate monospecific genus Piptadeniastrum to house Piptadeniastrum africanum , a tall, unarmed tree from west-central sub-Saharan Africa reminiscent of Newtonia Baill. in its fruits that dehisce along one suture while the valves remain attached along the other, and in its winged seeds, though differing in its often-alternate pinnae, glabrous floral structures and point of funicular attachment at the middle edge of the longest axis of the seed.

Taxonomic references.

Brenan (1959); Villiers (1989).

Figures

Figure 120. Entada clade variation in habit A Entada rheedei Spreng., huge woody liana, India B Entada wahlbergii Harv., thin woody climber in fruit, Benin C Entada leptostachya Harms, scandent shrub in fruit, Madagascar D Entada burkei (Benth.) S. A. O'Donnell & G. P. Lewis, erect shrub, South Africa E Entada abyssinica Steud. ex A. Rich., small tree, Rwanda F Entada elephantina (Burch.) S. A. O'Donnell & G. P. Lewis, geoxylic suffrutex, South Africa G Aubrevillea platycarpa Pellegr., large tree with plank buttresses, Guinea H Piptadeniastrum africanum (Hook. f.) Brenan, large tree with aliform buttresses, Guinea I P. africanum, large tree in forest canopy, Sierra Leone. Photo credits A Shiwali Samant, iNaturalist (https: // www. inaturalist. org / photos / 58810243) B M Schmidt, Dressler et al. (2014) C merveille, iNaturalist (https: // www. inaturalist. org / photos / 102007815) D pete _ leroux, iNaturalist (https: // www. inaturalist. org / photos / 184645340) E jordivanoort, iNaturalist (https: // www. inaturalist. org / photos / 31303989) F AE van Wyk G-I X van der Burgt.

Figure 121. Entada clade variation in foliage and flowers A Entada rheedei Spreng., young bipinnate leaf terminating in a bifurcate tendril (modified terminal pinnae pair), India B Entada tuberosa R. Vig., bipinnate leaf terminating in a bifurcate, thickened tendril (modified terminal pinnae pair), and rachis and rachillae terminating in a yellowish glandular mucro, Madagascar C Entada mannii (Oliv.) Tisser., oblong leaflets with rounded apices and midvein positioned centrally, Republic of Congo D Entada obliqua (Burtt Davy) S. A. O'Donnell & G. P. Lewis, asymmetric leaflets with acute apices and midvein positioned closer to distal margin, South Africa E Aubrevillea platycarpa Pellegr., oblong-obovate leaflets with emarginate apices, Guinea F Piptadeniastrum africanum (Hook. f.) Brenan, finely divided bipinnate leaves, Benin G E. rheedei, subsessile flowers with greenish-yellow corollas and cream-coloured stamen filaments, India H Entada stuhlmannii (Taub.) Harms, spiciform raceme of flowers with deep red corolla and stamen filaments, Mozambique I P. africanum, spiciform raceme of flowers with yellowish-white corolla (base of petals tinged pinkish) and stamen filaments, and red anthers with a white apical anther gland, Republic of Congo J P. africanum, terminal panicles of spiciform racemes, Republic of Congo. Photo credits A Shiwalee Sawant, iNaturalist (https: // www. inaturalist. org / photos / 58810126) B Andry. A. R, iNaturalist (https: // www. inaturalist. org / photos / 30264619) C DJ Harris, Dressler et al. (2014) D Andrew Hankey, iNaturalist (https: // www. inaturalist. org / photos / 3213785) E X van der Burgt F G Georgen, Dressler et al. (2014) G Dinesh Valke, iNaturalist (https: // www. inaturalist. org / photos / 133409879) H © Warren McCleland, all rights reserved, iNaturalist (https: // www. inaturalist. org / photos / 152390385) I-J X van der Burgt.

Figure 122. Entada clade variation in fruits and seeds A Entada rheedei Spreng., mature, gigantic, torulose, slightly curved, segmented craspedium with woody endocarp, India B Entada gigas (L.) Fawc. & Rendle, mature, laxly spirally twisted, segmented craspedium, Costa Rica C Entada spiralis Ridl., immature, tightly spirally twisted, segmented craspedium, Singapore D Entada africana Guill. & Perr., mature, segmented craspedia, distinctly umbonate over seeds, with exocarp peeling away, Togo E Entada polystachya (L.) DC., mature, segmented craspedia, slightly umbonate over seeds, with exocarp already shed, Costa Rica F Entada dolichorrhachis Brenan, mature, small, torulose, slightly curved, segmented craspedium, Zambia G Entada burkei (Benth.) S. A. O'Donnell & G. P. Lewis, immature craspedia, not segmented, South Africa H E. burkei, mature craspedia, not segmented, entire valves breaking away from replum, exocarp peeling away, South Africa I Entada goetzei (Harms) Harms, immature, elongate craspedia, not segmented, distinctly umbonate over seeds, Mozambique J Aubrevillea platycarpa Pellegr., papery, indehiscent fruits with twisted bases (holotype A Aubreville 990, MNHN-P-P 00418246), Cote d'Ivoire K Piptadeniastrum africanum (Hook. f.) Brenan, coriaceous pods, dehiscent along single suture, Democratic Republic of Congo L P. africanum, flattened, oblong seeds surrounded by broad, membranous wing, with funicle attached at middle of long axis of seed, Uganda M E. gigas, large, laterally compressed, cordate seed without pleurogram, collected in beach wrack, USA N E. rheedei, large, laterally compressed, globular seeds without pleurogram, South Africa O E. africana, laterally compressed, elliptic seeds with closed pleurogram, Togo P E. burkei, globular seed without pleurogram, South Africa. Scale bars: 1 cm (M); 2 cm (N); 5 mm (O, P). Photo credits A Dinesh Valke, iNaturalist (https: // www. inaturalist. org / photos / 159405372) B Pedro Blanco, iNaturalist (https: // www. inaturalist. org / photos / 181372721) C Cerlin Ng CC BY-NC-SA 2.0 D B Eichhorn, Dressler et al. (2014) E Marvin Lopez M, iNaturalist (https: // www. inaturalist. org / photos / 181531329) F W McCleland, Dressler et al. (2014) G P van Wyk; H tjeerd, iNaturalist (https: // www. inaturalist. org / photos / 64689073) I BT Wursten, Hyde et al. (2022) J MNHN (2022) (CC BY 4.0) K P Latham, Dressler et al. (2014) L David Bygott, iNaturalist (https: // www. inaturalist. org / photos / 62615168) M Robb Deans, iNaturalist (https: // www. inaturalist. org / photos / 2611187) N Ricky Taylor, iNaturalist (https: // www. inaturalist. org / photos / 44440338) O B Eichhorn, Dressler et al. (2014) P Joseph Heymans, iNaturalist (https: // www. inaturalist. org / photos / 123571608).

Figure 125. Distribution of Piptadeniastrum based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.