The genera of Leguminosae-Caesalpinioideae & Swartzieae
Type species: Z. punctata Cav.
Habit and leaf form. Glutinous shrubs; without specialized short shoots; unarmed.
Phyllotaxy spiral. The leaves compound; pinnate; paripinnate; with rachides adaxially ridged. The leaflets leathery, many per leaf (about 20); densely glandular, opposite or sub-opposite, or alternate. Stipules minite, absent or early caducous or very inconspicuous in mature leaves; membranous. Stipels absent.
Inflorescence and floral morphology. The inflorescences terminal; simple racemes. The flowers not distichous. Bracts small, very caducous, absent at anthesis. Bracteoles absent; absent at anthesis.
The flowers hermaphrodite; very zygomorphic, pentamerous; coloured. Floral tube length relative to total hypanthium + calyx length about 0.25. Hypanthium present; turbinate. Calyx 5; covering the rest of the flower in bud; not Swartzieae type; polysepalous; more or less regular to markedly irregular (the sepals slightly unequal, the lowermost one outside and modified); members imbricate. Corolla present; slightly irregular (the petals obovate-orbicular, slightly unequal, the vexillum broader); 5; without greatly reduced members; polypetalous. Petals imbricate; imbricate-ascending; yellow. The androecium comprising 10 members; declinate; members all free of one another (their filaments basally pilose); comprising only fertile stamens. Fertile stamens 10. Anthers ovoid, uniform, attached well above the base of the connective; dehiscing introrsely; dehiscing longitudinally. Ovary stipitate; free. Stigma not dilated (concave on the filiform style). Ovules solitary.
Fruit, seed and seedling. Fruit a two-valved pod (this gall-like, with long stiff bristles, 1-seeded); short, subovate, compressed; not noticeably winged. Seeds non-endospermic; with a straight or slightly oblique radicle.
Transverse section of lamina. Leaves without conspicuous phloem transfer cells in the minor veins. Druses common in the mesophyll. Mesophyll secretory cavities absent. Adaxial hypodermis absent. Leaf girders absent. Laminae isobilateral, with adaxial and abaxial palisades. 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; smooth. No compound or branched eglandular hairs seen. Capitate glands present. 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; conspicuously pitted; medium-thick. Stomata adaxially common and widespread. Abaxial: Abaxial stomata not predominantly paracytic (actinocytic & imperfect-paracytic). Abaxial epidermis not papillate. Abaxial interveinal epidermal cell walls straight, or gently undulating; conspicuously pitted in optical section; staining normally with safranin; medium-thick.
Wood anatomy. Wood with septate fibres; storied, or not storied. Intervascular pits very small.
Pollen ultrastructure. Tectum reticulate; finely to moderately regularly reticulate; Chile, Argentina. Length of colpi greater than one half pole to pole distance (with a margocolpus).
Species number and distribution. 1 species (Z. punctata).
Miscellaneous. Illustrations: • Z. punctata (Ulibarri 2005). • Z. punctata: TS of leaflet.
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. delta-intkey.com/caes’.