Fillaeopsis Harms, Bot. Jahrb. 26: 258. 1899.

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

Fillaeopsis Harms, Bot. Jahrb. 26: 258. 1899.

Figs 127 , 130

Type.

Fillaeopsis discophora Harms

Description.

Large, often buttressed, trees 24-40 m, 40-80 (100) cm diameter (Fig. 127C ), unarmed, bark smooth with vertical fissures, slash exuding pale yellow sticky latex, brachyblasts absent. Stipules not observed. Leaves bipinnate, extrafloral nectaries absent; pinnae 1-3 pairs, opposite; leaflets alternate, 4-6 (10) per pinna, venation brochidodromous. Inflorescence a panicle of spiciform racemes, axillary or terminal (Fig. 127G ), flowers abscising to leave peg-like pedicels. Flowers very waxy and shiny on herbarium sheets; calyx broadly open, 5-lobed, probably somewhat succulent; petals 5, fleshy, free; stamens 10, free, anthers ovate with a sessile, globose apical gland; pollen in tetrahedral tetrads with tricolporate grains, exine smooth (perforated), columellae present; large intra-staminal nectary disk surrounding the ovary; ovary sessile, stigma porate. Fruits very large, 60-80 × 15-20 cm, broadly oblong (Fig. 127L ), flattened, dehiscent along both sutures, 8-10-seeded; valves papery to coriaceous, outer layer waxy, with raised reticulate venation, endocarp smooth, papery, brown with whitish fibrous layers between the seeds which are transverse in legume. Seeds large, flattened, membranous-winged, 10-15 × 2.5-4 cm, wing to 2.5-3 cm wide (Fig. 127M ), testa membranous, funicle attached near the middle of the seed, pleurogram absent, endosperm lacking.

Chromosome number.

Unknown.

Included species and geographic distribution.

Monospecific ( F. discophora ), restricted to central Africa in Cameroon, Central African Republic, Democratic Republic of Congo, Equatorial Guinea, Gabon, Nigeria, Republic of Congo (Fig. 130 ).

Ecology.

Large canopy-emergent trees growing in closed-canopy evergreen lowland tropical rainforests (Fig. 127C ). Seeds wind-dispersed.

Etymology.

From Greek Fillaea - (a legume genus name, now a synonym of Erythrophleum ), and - opsis (= appearance) and hence named for its resemblance to the genus Fillaea .

Human uses.

The wood is light and mainly used for veneer and plywood ( Yvon 1975).

Notes.

Fillaeopsis forms its own monogeneric (and monospecific) lineage embedded in the grade that subtends the core mimosoid clade (Fig. 126 ). The fruits of Fillaeopsis and the winged seeds are amongst the largest known in Mimoseae , indeed across all Caesalpinioideae (Fig. 127L, M ), underpinning wind dispersal of the seeds, which also characterises the genera Plathymenia and Newtonia .

The leaves of Fillaeopsis are very similar to those of Cylicodiscus , although flowers and fruits of the two genera are quite different. When sterile the two genera can be distinguished by the following characters: Fillaeopsis lacks a gland at the apex of the petiole, whereas Cylicodiscus has a small, sunken gland; leaflets of Fillaeopsis have a conspicuous marginal vein and are elliptical in shape, whereas leaflets of Cylicodiscus have an inconspicuous marginal vein and are ovate.

Taxonomic references.

Harms (1899); Villiers (1989), both with illustrations.

Figures

Figure 126. Phylogenetic relationships across the grade Newtonia of four genera subtending the core mimosoid clade in tribe Mimoseae. For description of phylogeny and support values, see Fig. 6 caption (page 63).

Figure 127. Habit, habitats, inflorescences, and fruits of Newtonia and allies A small tree of Anonychium africanum (Guill. & Perr.) C. E. Hughes & G. P. Lewis in Senegal, West Africa B small twisted treelet of Plathymenia reticulata Benth. in savanna grasslands (Cerrado) in eastern Bolivia C large, buttressed tree base of Fillaeopsis discophora Harms in tropical wet forest, Ebo, Cameroon D large buttressed tree base of Newtonia buchananii (Baker f.) G. C. C. Gilbert & Boutique in semi-evergreen forest in Mozambique E spicate inflorescence of Anonychium africanum F spicate inflorescences of Plathymenia reticulata, eastern Bolivia G spicate inflorescences of Fillaeopsis discophora, Gabon H spicate inflorescences of Newtonia buchananii in Malawi I indehiscent pods of Anonychium africanum collected as livestock feed in Burkina Faso, West Africa J tardily dehiscent pods with chartaceous or weakly coriaceous valves of Plathymenia reticulata, eastern Bolivia K pod valves and papery endocarp packets surrounding seeds of Plathymenia reticulata, Bahia, Brazil L tardily dehiscent pods with chartaceous valves of Fillaeopsis discophora in tropical wet forest in Mayombe, Congo (Brazzaville) M large winged seeds of Fillaeopsis discophora in tropical wet forest in Ambam, Cameroon N fruits and winged seeds of Newtonia buchananii in cultivation in South Africa. Photo credits A S Christensen www. westafricanplants. senckenberg. de B, F, J, K, N CE Hughes C, L, M X van der Burgt D Stefaan Dondeyne E M Arbonnier https: // agritrop. cirad. fr / G E Bidault, Missouri Botanical Garden, http: // legacy. tropicos. org / Image / 100618759 H G Baumann www. westafricanplants. senckenberg. de I M Schmidt www. westafricanplants. senckenberg. de.

Figure 130. Distribution of Fillaeopsis based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.