Calliandra Benth., J. Bot. (Hooker) 2(11): 138. 1840

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

Calliandra Benth., J. Bot. (Hooker) 2(11): 138. 1840 nom. cons.

Figs 197 , 198 , 199 , 202

Anneslia Salisb., Parad. Lond.: pl. 64. 1807, nom. ut. rej. vs. Calliandra Benth. Type: Anneslia falcifolia Salisb. [≡ Calliandra houstoniana (Mill.) Standl.]

Clelia Casar., Nov. Stirp. Brasil. Dec. 10: 83. 1845. Type: Clelia ornata Casar. [≡ Calliandra harrisii (Lindl.) Benth.]

Codonandra H. Karst., Fl. Columb. 2: 43, t. 122. 1863. Type: Codonandra purpurea H. Karst. [≡ Calliandra magdalenae (DC.) Benth. var. magdalenae ]

Guinetia L. Rico & M. Sousa, Kew Bull. 54(4): 977. 1999 (publ. 2000). Type: Guinetia tehuantepecensis L. Rico & M. Sousa [≡ Calliandra tehuantepecensis (L. Rico & M. Sousa) E.R. Souza & L.P. Queiroz]

Type.

Calliandra houstoniana (Mill.) Standl. [≡ Mimosa houstoniana Mill.]

Description.

Shrubs or small trees (Fig. 197C, E-H ), rarely functionally herbaceous or geoxylic subshrubs with an enlarged xylopodium seasonally arising from a perennial root (Fig. 197I-K ), usually unarmed, very rarely armed with long shoots tapering at apex into a stout thorn or with spinescent stipules. Stipules leafy or rarely spinescent, persistent or caducous. Leaves bipinnate, pinnate only in C. hymenaeoides ; petioles and rachis without extrafloral nectaries; pinnae 1-many pairs; leaflets (1) 2-many pairs per pinnae, small (ca. 5 mm) to up to 12 cm long, size usually being inversely proportional to number of leaflet pairs per pinna. Inflorescences capitate or umbelliform (Fig. 198G-L ), usually pedunculate, solitary or fasciculate, arising from leaf axils or from brachyblasts, sometimes with the umbels forming a long, terminal pseudoraceme through suppression of distal leaves (Fig. 198D-F ); capitula either homomorphic or heteromorphic, the latter bearing 1 to several large, central flowers and numerous small, lateral flowers (Fig. 198H ). Flowers bracteate, hermaphroditic or functionally staminate; calyx usually cup-shaped to turbinate, rarely hemispherical or inflated, (3) 5 (6)-merous; corolla cup-shaped to tubular, (3) 5 (6)-merous; stamens (8) 10-numerous, long exserted from the corolla, always with the base fused forming a conspicuous tube, this disproportionately long and exserted in the central flowers of heteromorphic inflorescences, red, pink or white, or white in the basal half and pink or red in the distal half, rarely bright yellow (Fig. 198D-L ); anthers eglandular; pollen in 8-grained polyads, these calymmate, bilateral, flattened-ovoid, with the basal grain acutely narrowed and bearing a sticky appendage; ovary sessile or short pedicellate, usually 8-12-ovulate; stigma discoid or capitate with a wide area of polyad receptivity. Fruits narrowly oblanceolate to linear-oblanceolate, flattened, straight or slightly curved, with thickened margins, the valves usually coriaceous to ligneous, often erect (Fig. 199C-J ), dehiscing elastically along both margins, recurving from apex downwards (Fig. 199D ). Seeds discoid, ovoid or rhomboid, usually compressed, with or without U-shaped pleurogram.

Chromosome number.

n = 8, 11 ( Goldblatt 1981b; Hernández 1986, 1989; Tapia-Pastrana and Uribe-Hernández 2019).

Included species and geographic distribution.

Approximately 140 species restricted to the Neotropics, occurring from southern United States (southern Arizona, New Mexico and Texas), throughout Mexico, Central America and South America, south to Uruguay, and northern Argentina and Chile (Fig. 202 ). Areas of high species concentration and endemism exist in north-eastern Brazil and in western and southern Mexico. A particularly important area of species richness corresponds to the campos rupestres of Serra do Espinhaço in north-eastern Brazil, where ca. 37 endemic species occur, these forming a clade that corresponds to section Calliandra Monticola E.R. Souza & L.P. Queiroz. Koenen et al. (2013) showed that this clade is recent, dating to the Pliocene and is explained by an acceleration in the rate of species diversification, showing that this campos rupestres clade represents a remarkable example of a recent, rapid evolutionary radiation.

Ecology.

Most species occur at low or moderate elevations, in seasonally dry tropical deciduous forests, and less frequently in wet forests, riparian vegetation, tropical savannas, campos rupestres (rupestrian grasslands) from Espinhaço range in eastern Brazil, temperate grasslands, and even in semi-desert or desert vegetation. Seeds disperse over short distances through the explosive dehiscing mechanism. Most Mesoamerican and Mexican species have nocturnal anthesis and are legitimately pollinated by sphingid moths or bats; however, hummingbird pollination in day-flowering species appears to be also common in the genus.

Etymology.

From Greek, calli - (= beautiful) and - andrus (= male), pertaining to the highly attractive stamens.

Human uses.

Calliandra calothyrsus Meissn. has proved to be an excellent fast-growing, multi-use shrub or small tree as a source of fuelwood and fodder, as well as for soil improvement ( Macqueen and Hernández 1997). Some species, most notably C. haematocephala (Bertero ex DC.) Benth., C. californica Benth. and C. riparia Pittier, are planted as ornamentals in urban areas.

Notes.

For over a century, after publication of Bentham’s (1875) influential treatment of suborder Mimoseae , Calliandra was understood to be a genus from both the New and Old Worlds. However, this concept has been modified over the last three decades. Species of Bentham’s ser. Calliandra Laetevirentes , together with other species, were segregated into the Neotropical genus Zapoteca ( Hernández 1986, 1989). Barneby (1998) explicitly restricted Calliandra to the New World species in his monograph of the genus, even though he did not assign the Old World species to new segregate genera. His work anticipated the subsequent description of segregate genera that were confirmed by molecular phylogenies. Species from Madagascar were placed in Viguieranthus ( Villiers 2002). In addition, the continental African species ( C. redacta and C. gilbertii ), were transferred to Afrocalliandra ( Souza et al. 2013), and C. cynometroides Beddome, from India, to Sanjappa ( Souza et al. 2016).

Phylogenetic analyses using morphological and molecular sequence data have shown that all the American species of Calliandra , plus the monotypic Guinetia L. Rico & M. Sousa, later transferred to Calliandra [ C. tehuantepecensis (L. Rico & M. Sousa) E.R. Souza & L.P. Queiroz], constitute a monophyletic group ( Souza et al. 2013). Therefore, Calliandra , in this more restricted concept, is a Neotropical genus defined by the following combination of characters: elastically dehiscent pods; 8-grained, bisymmetric, calymmate polyads with a large mucilaginous basal appendage; and atypical (n = 8 and 11) chromosome numbers ( Guinet and Hernández 1989; Hernández 1989; Barneby 1998).

The generic placement of one Asian species, C. umbrosa (Wall.) Benth. from India, Bangladesh and Myanmar, which is still included in Calliandra , remains to be evaluated2. It is characterised by having spinescent stipules, 3-foliolate pinnae, petioles with extrafloral nectaries, and discoid, 16-grained, acalymmate polyads, and certainly does not belong to Calliandra as currently understood. Likewise, an undescribed species of Calliandra , excluded from the genus by Barneby (1998), also does not group with the rest of the genus (Fig. 203 ; Ringelberg et al. 2022), occurring instead as sister to Sanjappa E.R. Souza & Krishnaraj in the Zapoteca clade (page 371).

Taxonomic references.

Barneby (1998); Macqueen and Hernández (1997); Souza et al. (2013).

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 197. Diversity of plant growth forms of the genera of the Calliandra clade A shrubby habit of Acaciella angustissima (Mill.) Britton & Rose var. angustissima, Texas, USA B treelet of Acaciella angustissima var. angustissima, Chiquimula, Guatemala (Hughes 1487) C shrub of Calliandra mollissima (Humb. & Bonpl. ex Willd.) Benth., Maranon Valley, Peru (Saerkinen 2198) D stunted xerophytic shrublet of Afrocalliandra redacta (J. H. Ross) E. R. Souza & L. P. Queiroz, Kuboes, South Africa E stunted xerophytic shrublet of Calliandra chilensis Benth., northern Chile F small treelet of Calliandra calothyrsus Meisn., Siguatepeque, Honduras G shrub of Calliandra californica Benth., Baja California Sur, Mexico (Hughes 1546) H treelet of Calliandra fuscipila Harms, Serra do Espinhaco, Bahia, Brazil (Queiroz 15626) I, J functionally herbaceous geoxyle of Calliandra longipes Benth. arising from a stout lignotuber and resprouting and fruiting after fire in savanna woodland, Santa Cruz, Bolivia (Wood 26548) K geoxylic shrublet of Calliandra mucugeana Renvoize, arising from a stout woody underground stem and forming carpet-like thickets, Serra do Espinhaco, Bahia, Brazil (Queiroz 15540). Photo credits A Ron Stephens, iNaturalist (https: // www. inaturalist. org / photos / 199321699) B, C, F-K CE Hughes D Pietermier, iNaturalist (https: // www. inaturalist. org / photos / 152398478) E J Jimenez Castillo.

Figure 198. Variation in inflorescences of the genera of the Calliandra clade. A compound terminal panicle of capitula of Acaciella villosa (Sw.) Britton & Rose, Oaxaca, Mexico (Hughes 1333) B capitula of Acaciella villosa, Piura, Peru (Hughes 2635) C flowers of Afrocalliandra redacta (J. H. Ross) E. R. Souza & L. P. Queiroz, Kuboes, South Africa D erect terminal racemose inflorescence of Calliandra calothyrsus Meisn. flowering at night, Siguatepeque, Honduras (Macqueen 3) E erect terminal racemose inflorescence of Calliandra juzepczukii Standl., Oaxaca, Mexico (Hughes 1675) F erect terminal inflorescence with buds and flowers opening acropetally, Calliandra grandiflora (L'Her.) Benth., Mexico City, Mexico G inflorescence of Calliandra taxifolia (Kunth) Benth., Mollendo, Arequipa, Peru (Hughes 2357) H heteromorphic inflorescence of Calliandra mollissima (Humb. & Bonpl. ex Willd) Benth., Maranon Valley, Peru, showing central flowers with enlarged staminal tubes (Saerkinen 2198) I Calliandra nebulosa Barneby, Serra do Espinhaco, Bahia, Brazil (Queiroz 15624) J flowers of Calliandra longipinna Benth., Serra do Espinhaco, Bahia, Brazil (Queiroz 15603) K long pedicellate flowers of Calliandra leptopoda Benth., Serra do Espinhaco, Bahia, Brazil L leaves, foliaceous stipules and terminal inflorescences of Calliandra lanata Benth., Serra do Espinhaco, Bahia, Brazil. Photo credits A, B, D, E, G-J CE Hughes C Pietermier, iNaturalist (https: // www. inaturalist. org / photos / 15308160) F Mvz-juangonzalezromero, iNaturalist (https: // www. inaturalist. org / photos / 195966667) K, L E de Souza.

Figure 199. Variation in fruits across genera of the Calliandra clade A pendulous fruit of Acaciella angustissima (Mill.) Britton & Rose var. angustissima, Chiapas, Mexico B erect fruit and spinescent stipules of Afrocalliandra redacta (J. H. Ross) E. R. Souza & L. P. Queiroz, Kuboes, South Africa C, D fruits of Calliandra taxifolia (Kunth) Benth., Mollendo, Arequipa, Peru (Hughes 2357) C unripe green erect fruits D ripe fruits elastically dehiscent from the apex, the valves recurved backwards E ripe and unripe fruits of Calliandra luetzelburgii Harms, Serra do Espinhaco, Bahia, Brazil (Queiroz 15618) F unripe, green, erect fruits of Calliandra viscidula Benth., Serra do Espinhaco, Bahia, Brazil (Queiroz 15541) G, H fruits of Calliandra houstoniana (Mill.) Standl., Chiapas, Mexico (Hughes 1271 & 1287) I unripe fruits of Calliandra chilensis Benth., northern Chile J unripe, erect fruits of Calliandra bahiana Renvoize var. erythematosa Barneby, Serra do Espinhaco, Bahia, Brazil (Queiroz 15622). Photo credits A Neptali Ramirez Marcial, iNaturalist (https: // www. inaturalist. org / photos / 199788369) B Pietermier, iNaturalist (https: // www. inaturalist. org / photos / 152398411) C-H, J CE Hughes I J Jimenez Castillo.

Figure 202. Distribution of Calliandra based on quality-controlled digitised herbarium records. See Suppl. material 1 for the source of occurrence data.

Figure 203. Generic relationships in the Zapoteca clade (tribe Mimoseae). Note that Calliandra p. p. represents a single taxon, which is currently unplaced [and is not the type species of Calliandra (see tribe notes and footnote on page 382)]. For description of phylogeny and support values, see Fig. 6 caption (page 63).