Sclerolobieae Benth. & Hook. f., Gen. Pl. 1: 436. 1865.

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

Tribe Sclerolobieae Benth. & Hook. f., Gen. Pl. 1: 436. 1865.

Figs 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86

Tachigalieae Nakai, Chosakuronbun Mokuroku [Ord. Fam. Tr. Nov.]: 252. 1943. Type: Tachigali Aubl.

Type.

Sclerolobium Vogel [= Tachigali Aubl.]

Included genera

(5). Arapatiella Rizzini & A. Mattos (2 species), Diptychandra Tul. (2), Jacqueshuberia Ducke (7), Moldenhawera Schrad. (12), Tachigali Aubl. (80-90).

Description.

Trees or shrubs, unarmed. Stipules present, persistent or caducous. Leaves pinnate or bipinnate, usually paripinnate, rarely imparipinnate; myrmecophilous domatia present or absent; leaflets opposite; extrafloral nectaries absent. Inflorescences terminal or lateral racemes or panicles. Flowers bisexual, bilaterally or radially symmetrical; hypanthium cupular or cylindrical; sepals 5, free or rarely connate at base; petals 5, free, equal or the dorsal, standard petal differentiated; stamens often 10 (18), rarely only one stamen and 7 or 9 staminodes, free or connate, monomorphic or dimorphic, anthers longitudinally dehiscent, rarely opening through pores; pollen in monads, rarely in tetrads or associated with viscin threads, the exine scabrate-punctate to reticulate; ovary sessile or stipitate; nectary disk absent. Fruit dehiscent along both sutures or indehiscent with flaking exocarp. Seeds ellipsoid to obovoid, laterally compressed or complanate, sometimes winged, seed coat hard or soft, endosperm scarce.

Distribution.

Mostly Neotropical, extending from Central to South America, in tropical rainforests, tropical cloud forests, seasonally dry forests, and fire-prone savannas.

Clade-based definition.

The most inclusive crown clade containing Moldenhawera floribunda Schrad. and Tachigali guianensis (Benth.) Zarucchi & Herend., but not Caesalpinia brasiliensis L., Dimorphandra conjugata (Splitg.) Sandwith or Mimosa sensitiva L. (Fig. 78 ).

Notes.

Although the generic name Sclerolobium is currently treated under Tachigali , the tribe name Sclerolobieae ( Bentham 1865) has priority over Tachigalieae ( Nakai 1943). Tribe Sclerolobieae , as herein circumscribed based on phylogenomic analyses ( Ringelberg et al. 2022), includes five genera (Fig. 78 ), most of which were never closely associated with each other in traditional classifications of Caesalpinioideae ( Polhill and Vidal 1981; Polhill 1994; Lewis 2005b; Ulibarri 2008). For example, Polhill and Vidal (1981) treated Tachigali and Diptychandra as part of the Sclerolobium group of the old sense tribe Caesalpinieae , whereas Arapatiella , Jacqueshuberia , and Moldenhawera were classified together with ten other Caesalpinioideae genera in the Peltophorum group of the same tribe.

Not only have the relationships amongst Sclerolobieae genera now been strongly resolved for almost all nodes (Fig. 78 ), but also their monophyly is strongly supported by morphological characters and more densely sampled phylogenies based on a few plastid and nuclear loci ( Haston et al. 2003, 2005; Bruneau et al. 2008; Chomicki et al. 2015; Huamantupa-Chuquimaco 2020). The tribe is not defined by obvious synapomorphies, although there is a tendency for the occurrence of unusually divided or foliaceous stipules (except for Diptychandra ). The genera are distinct in leaf morphology (pinnate or bipinnate leaves) (Fig. 79 ), floral symmetry (radial or bilateral), pollination syndrome (bees or birds), pollen presentation (monads or tetrads), fruit morphology, seed morphology (winged or non-winged), and dispersal syndrome (autochory, hydrochory, or anemochory). The high morphological variation found within Sclerolobieae in terms of floral architecture (Fig. 80 ) and fruit type (Fig. 81 ) may explain why its constituent genera have long remained unnoticed as belonging to the same natural group. For example, Tachigali and Diptychandra have similarly small flowers, which are mostly radially symmetrical, but ontogenetically the apparently morphologically homogeneous flowers of Tachigali display considerable variation ( Casanova et al. 2020) and are quite different from those of Diptychandra . Many Tachigali species also possess bilaterally symmetrical flowers, with a curved hypanthium similar to the much bigger flowers of Arapatiella and Jacqueshuberia . The Moldenhawera flowers are striking in their more or less radially symmetrical Malpighiaceae -like architecture, where the often-yellow petals are marginally crimped and long-clawed, and the cluster of staminodes are much smaller than the single bearded fertile stamen and resemble the oil glands (elaiophores) typical of the Malpighiaceae flowers ( Queiroz et al. 2023). The fruits are wind-dispersed, compressed cryptosamaras in Tachigali , whereas all other genera in the tribe have elastically dehiscent, laterally compressed pods. Within Sclerolobieae there is also a high degree of variation in pollen ( Graham and Barker 1981; Banks et al. 2003; Banks and Lewis 2018), which can be colporate, in monads or tetrads, and with scabrate-punctate to reticulate ornamentation; pollen connecting viscin threads are present in Arapatiella and Jacqueshuberia . Faria et al. (2022) report nodulation with a fixation thread type of nodule anatomy in at least one species each of Moldenhawera , Tachigali , Jacqueshuberia , and a confirmed absence of nodulation in Arapatiella (unknown in Diptychandra ).

Figures

Figure 6. Generic relationships in tribe Ceratonieae. Left part of figure shows complete genus-level Caesalpinioideae phylogeny with the Ceratonieae indicated with a red rectangle. Branch lengths are expressed in coalescent units and terminal branches were assigned an arbitrary uniform length for visual clarity. Support for relationships is based on fractions of supporting and conflicting gene trees: pie charts show gene tree support and conflict per node (blue representing supporting gene trees, green gene trees supporting the most common alternative topology, red gene trees supporting further alternative topologies, grey gene trees uninformative for this node), and numbers above pie charts are Internode Certainty All support values [both calculated with PhyParts (Smith et al. 2015)]. If present, red numbers below pie charts are non-significant (i. e.> 0.05) outcomes of ASTRAL's polytomy test (Sayyari and Mirarab 2018), which tests for each node whether the polytomy null model can be rejected. Monophyletic genera are represented by single branches; see Suppl. material 2 for a phylogeny with all accessions. See Suppl. material 3 for gene tree support across the phylogeny. The phylogeny is a pruned version of the backbone phylogeny of Ringelberg et al. (2023), where full details of the data and phylogenomic analysis methods are presented.

Figure 78. Generic relationships in tribe Sclerolobieae. For description of phylogeny and support values, see Fig. 6 caption (page 63).

Figure 79. Vegetative morphology of Sclerolobieae A Moldenhawera nutans L. P. Queiroz, G. P. Lewis & Allkin shrubby individual in a Restinga sand dune field B Diptychandra aurantiaca (Mart.) Tul. tree in a Caatinga seasonally dry setting C Arapatiella psilophylla (Harms) R. S. Cowan flowering tree D Tachigali amplifolia (Ducke) Barneby large, buttressed tree E Jacqueshuberia purpurea Ducke pinnate stipule F leaf G detail of a leaf H Tachigali rugosa (Mart. ex Benth.) Zarucchi & Pipoly leaf with characteristic inversely symmetrical leaflets I, J Tachigali sp. details of leaf domatia K, L variation in stipule shape. Photo credits A, C, E-L D Cardoso B RT Queiroz https: // rubens-plantasdobrasil. blogspot. com / D I Huamantupa.

Figure 80. Floral morphology of Sclerolobieae A Moldenhawera lushnathiana Yakovlev highly branched inflorescence B Moldenhawera nutans L. P. Queiroz, G. P. Lewis & Allkin flowering branch, showing the typical navicular leaves with rust-coloured leaflet abaxial surface C flowers D Diptychandra aurantiaca (Mart.) Tul. flowering branch E inflorescence F Arapatiella psilophylla (Harms) R. S. Cowan inflorescences G flowers H Jacqueshuberia purpurea Ducke flower I Tachigali macrostachya Huber candelabrum-like inflorescences J Tachigali amarumayu Huamantupa, H. C. Lima & D. B. O. S. Cardoso densely paniculate inflorescences K Tachigali paraensis (Huber) Barneby radially symmetrical flowers L Tachigali paniculata Aubl. bilaterally symmetrical flowers M Tachigali macrostachya bilaterally symmetrical flowers. Photo credits A LP Queiroz B, C, F, G, I, K-M D Cardoso J I Huamantupa D, E RT Queiroz https: // rubens-plantasdobrasil. blogspot. com / H M Cohn-Haft.

Figure 81. Fruit morphology of Sclerolobieae A Moldenhawera polysperma (Vell.) Stellfeld old fruit valves B Diptychandra aurantiaca (Mart.) Tul. fruits C fruit opened showing the characteristic winged seed D Arapatiella psilophylla (Harms) R. S. Cowan immature fruit E Jacqueshuberia purpurea Ducke immature fruits F Tachigali macrostachya Huber immature fruits G Tachigali rugosa (Mart. ex Benth.) Zarucchi & Pipoly mature fruits. Photo credits A C Vivas B, C RT Queiroz https: // rubens-plantasdobrasil. blogspot. com / D-F D Cardoso G LP Queiroz.

Figure 82. Distribution of Moldenhawera based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.

Figure 83. Distribution of Diptychandra based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.

Figure 84. Distribution of Arapatiella based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.

Figure 85. Distribution of Jacqueshuberia based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.

Figure 86. Distribution of Tachigali based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.