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The genera of Leguminosae-Caesalpinioideae & Swartzieae

L. Watson and M.J. Dallwitz

Tachigalia Aubl.

Tachigali Aubl., Cuba Scop., Cubaea Schreb., Tachia Pers., Tassia Rich. ex DC., Valentinia Neck

Type species: T. paniculata Aubl.

Habit and leaf form. Trees; unarmed.

Phyllotaxy spiral. The leaves compound; pinnate; paripinnate; with adaxially grooved rachides (rachides often angular). The leaflets many per leaf, or few per leaf; opposite or sub-opposite; petiolulate; without noticeably twisted petiolules; leathery, symmetrical or nearly so; pinnately veined, with a predominant ‘midrib’. Stipules present, persistent and conspicuous in mature leaves, or absent or early caducous or very inconspicuous in mature leaves; leafy, or membranous (sometimes pinnate); not connate. Stipels absent.

Inflorescence and floral morphology. The inflorescences axillary, or terminal; unbranched, or branched; of racemose units; simple racemes (axillary), or panicles (terminal). The flowers with incurved-clavate buds. Bracts lanceolate or subulate, absent at anthesis. Bracteoles present (rarely), or absent; if present, absent at anthesis, or persistent beyond anthesis (rarely); not valvate.

The flowers hermaphrodite; zygomorphic, pentamerous, or not pentamerous throughout (rarely); departing from pentamery when non-pentamerous, in the androecium; coloured. Hypanthium present; obliquely turbinate tubular. The perianth comprising distinct calyx and corolla. Calyx 5; covering the rest of the flower in bud; polysepalous; markedly irregular (the outermost, abaxial member smaller); members imbricate. Corolla present; slightly irregular (the obovate petals slightl unequal, the adaxial one less oblique); 5; without greatly reduced members; polypetalous. Petals somewhat clawed to sessile; imbricate; imbricate-ascending; white, or yellow. Disk absent. The androecium comprising 10 members; declinate; members all free of one another; members all more or less equal in length, or markedly unequal (the adaxial 3 members often shorter and with thicker, incurved filaments); comprising only fertile stamens (the anthers ovate or oblong, uniform or those of the shorter, upper stamens smaller). Fertile stamens 10, or 15–16 (rarely). Anthers attached well above the base of the connective; dehiscing laterally; dehiscing longitudinally. Ovary shortly stipitate; eccentric, with the stipe adnate (to the middle of the hypanthium tube, or higher). Stigma small, dilated to not dilated (the style filiform). Ovules numerous.

Fruit, seed and seedling. Fruit a two-valved pod, or indehiscent; compressed, oblong; the valves leathery, not becoming woody. Seeds endospermic; not arillate; with a straight or slightly oblique radicle; amyloid-negative. Cotyledons of Type 4; with a vascular system in one plane.

Transverse section of lamina. Leaves with conspicuous phloem transfer cells in the minor veins. Druses absent from the mesophyll. Mesophyll secretory cavities absent. Adaxial hypodermis absent. Leaf girders common (the veins transcurrent). Laminae dorsiventral. Mesophyll without unaligned fibres or sclereids. Minor veins mainly with abundant accompanying fibres.

Leaf lamina epidermes. Epidermal crystals not seen either adaxially or abaxially. Simple unbranched hairs common; scabrid. No compound or branched eglandular hairs seen. Capitate glands not seen. Hooked hairs not seen. Cassieae-type leaf pseudo-glands not seen. Expanded and embedded hair-feet absent. Basally bent hairs present. Adaxial: Adaxial interveinal epidermal cell walls straight in optical section; not conspicuously pitted; thin. Stomata adaxially common and widespread, or adaxially very rare. Abaxial: Abaxial stomata predominantly paracytic. Abaxial interveinal epidermal cell walls of medium thickness.

Wood anatomy. Wood not storied.

Pollen ultrastructure. Tectum reticulate; finely to moderately regularly reticulate. Length of colpi greater than one half pole to pole distance. Foot layer of pollen wall smooth.

Cytology. Basic chromosome number, x = 13. 2n = 26.

Species number and distribution. 26 species. Central and tropical South America.

Tribe. Caesalpinieae.

Miscellaneous. Illustrations: • T. multijuga: Fl. Brasiliensis 15 (1870). • T. rusbyi, e.m. scanned pollen (Graham & Barker, 1981).

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, and classification. See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1993 onwards. The genera of Leguminosae-Caesalpinioideae and Swartzieae: descriptions, illustrations, identification, and information retrieval. In English and French. Version: 22nd March 2017.’.