Lysiloma Benth., London J. Bot. 3: 82. 1844.

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

Lysiloma Benth., London J. Bot. 3: 82. 1844.

Figs 212 , 214

Type.

Lysiloma schiedeanum Benth. [= Lysiloma divaricatum (Jacq.) J.F. Macbr.]

Description.

Unarmed small trees or shrubs. Stipules commonly submembranous, linear to obliquely dilated, semicordate, or flabellate, absent from all fruiting and most mature flowering specimens. Leaves bipinnate, extrafloral nectaries near or well above mid-petiole, sessile, either cupular or mounded, narrow-pored, and smaller nectaries often between some distal pinnae-pairs and toward tips of pinnae; pinnae 1-30 pairs; leaflets 1.5-50 pairs per pinna, venation simple, or weakly pinnate, or palmate-pinnate. Inflorescence either spicate-racemose, or spherical capitate, or hemispherical umbelliform. Flowers homomorphic or almost so, the central flower sometimes a little stouter, but never longer than the others; calyx campanulate, short-toothed; corolla tubular; stamens 12-32, joined into a tube at the base, exserted; pollen in 16-grained polyads, more or less isodiametric; ovary sessile or almost so, glabrous at anthesis. Fruit either a craspedium or an indehiscent legume, long persistent on tree, stipitate, in profile linear or oblong-elliptic, acute or obtuse, framed by prominent sutures, the papery-crustaceous valves plano-compressed except where crumpled or low-bullate over seeds, straight but sometimes twisted through 180° either above or below middle, the exocarp exfoliating to reveal the stramineous endocarp, less often not exfoliating in craspedial species, the valves separating from the persistent sutures and falling together out of the marginal frame, the seeds then released on the ground. Seeds transverse, compressed ellipsoid, funicle filiform, lustrous brown, pleurogram commonly U-shaped, sometimes semicircular, or closed.

Chromosome number.

2 n = 26 ( Jarolĭmovă 1994).

Included species and geographic distribution.

Eight species, in Mexico, Central America as far south as Costa Rica, and the Greater Antilles, one species reaching subtropical south Florida, and one species extending north into south-eastern Arizona in the USA (Fig. 214 ).

Ecology.

Predominantly seasonally dry tropical forests and adjacent arid and semi-arid thorn scrub in north-western Mexico and the southern USA, extending into mid-elevation pine-oak formations and weakly into wetter less seasonal lowland tropical rainforest. Generally on freely-drained soils, coastal sand dunes and shallow limestone soils. Most species are deciduous, flowering often coinciding with leaf flush at the end of the dry season. Fruits are often long persistent on the tree.

Etymology.

Derived from the Greek, Lysis (= to loose) and loma (= edge), referring to the shedding of the legume sutural frame (or edge) at fruit maturity (i.e., craspedial dehiscence).

Notes.

The carpological character that distinguishes most Lysiloma species from other New World ingoid genera is the craspedial fruit with sutures which usually persist as a frame after the valves have separated ( Barneby and Grimes 1997). However, not all species of Lysiloma have craspedial dehiscence in which the valves of the pods detach as a unit, together with the seeds, from the often persistent sutural frame. Two species have indehiscent fruits: L. latisiliquum (L.) Benth. and L. sabicu Benth.

Taxonomic references.

Barneby and Grimes (1997); Duno et al. (2021); Gale and Pennington (2004) with illustrations.

Figures

Figure 212. Morphology of Cojoba clade A-C Cojoba arborea (L.) Britton & Rose A habit B leaves C fruit D Cojoba graciliflora (S. F. Blake) Britton & Rose in Mexico, fruit E-G Hesperalbizia occidentalis (Brandegee) Barneby & J. W. Grimes E habit F trunk G leaves and fruits H Lysiloma candidum Brandegee, habit l Lysiloma acapulcense (Kunth) Benth. fruit J-N Lysiloma latisiliquum (L.) Benth. J habit K trunk L leaves and stipule M flowers N fruit O, P Lysiloma tergeminum Benth., fruits. Photo credits A-C GA Romero Gonzalez D, J-N R Duno de Stefano E-I, O, P CE Hughes.

Figure 214. Distribution of Lysiloma based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.