| # The genera of Leguminosae-Caesalpinioideae and Swartzieae |

L. Watson and M.J. Dallwitz

### Martiodendron Gleas.

Amphymenium Kunth, Martia Benth., MartiusiaBenth.

Type species: M. excelsum (Benth.) Gleason.

Habit and leaf form. Trees; unarmed.

Phyllotaxy spiral. The leaves compound; pinnate; imparipinnate. The leaflets few per leaf (about 7, in the best known species); ovate or elliptic, alternate; without noticeably twisted petiolules; symmetrical or nearly so; pinnately veined, with a predominant ‘midrib’. Stipules absent or early caducous or very inconspicuous in mature leaves (very caducous). Stipels absent.

Inflorescence and floral morphology. The inflorescences terminal; branched; of cymose units; panicles. The flowers not distichous. Bracts early caducous, absent at anthesis. Bracteoles present (at the pedicel bases); small, not enclosing the flower buds; early caducous, absent at anthesis.

The flowers showy; hermaphrodite; not pentamerous throughout; departing from pentamery in the androecium, or in the calyx and in the androecium; coloured. Hypanthium absent, the androecium hypogynous. The perianth comprising distinct calyx and corolla. Calyx 5; covering the rest of the flower in bud; polysepalous; more or less regular; members narrow, acuminate, imbricate to not imbricate (sub-valvate). Corolla present; slightly irregular to very irregular (the petals similar, but the posterior one somewhat broader); 5; without greatly reduced members; polypetalous (the petals oblong). Petals imbricate; imbricate-ascending (the posterior one inside); yellow. Disk absent. The androecium comprising 4–7 members; members all free of one another; members markedly unequal; comprising only fertile stamens. Fertile stamens 4–5, or 6–7 (rarely). Anthers unequal, the filaments very short attached at the base of the connective; dehiscing apically via pores or short slits. Ovary sessile or subsessile; free. Stigma small, terminating the subulate-curved style. Ovules few, or solitary.

Fruit, seed and seedling. Fruit thin, leathery, compressed, indehiscent; not drupaceous; large, oblong, straight; winged longitudinally; 2 winged (along the sutures); not becoming woody. The mature valves with conspicuous, prominent, raised venation; conspicuous venation predominantly longitudinal. Seeds with a straight or slightly oblique radicle; amyloid-negative; with galactomannan.

Transverse section of lamina. Leaves with conspicuous phloem transfer cells in the minor veins. Druses common in 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, or smooth. No compound or branched eglandular hairs seen. Capitate glands not seen. Hooked hairs present. 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, or not conspicuously pitted; medium-thick to of medium thickness. Stomata adaxially very rare. Abaxial: Abaxial stomata predominantly paracytic. Abaxial epidermis not papillate. Abaxial interveinal epidermal cell walls straight, or gently undulating; conspicuously pitted in optical section; staining normally with safranin.

Wood anatomy. Wood storied. Intervascular pits medium to large.

Pollen ultrastructure. Tectum punctate; smooth punctate, or puncticulate. Length of colpi greater than one half pole to pole distance.

Species number and distribution. 5 species (M. elatum, M. excelsum, M. fluminense, M. mediterraneum, M. parviflorum). Tropical South America.

Tribe. Cassieae.

Miscellaneous. Illustrations: • Martiodendron excelsum: Fl. Brasiliensis 15 (1870). • Martiodendron mediterraneum (as parvifolia): Fl. Brasiliensis 15 (1870).

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: 4th August 2019. delta-intkey.com’.

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