The genera of Leguminosae-Caesalpinioideae & Swartzieae
Type species: I. dunensis Wieringa.
Habit and leaf form. Small to large trees (with straight, cylindrical trunk and no buttresses); unarmed.
The leaves compound; pinnate; paripinnate. The leaflets few per leaf (1–2 jugate); opposite or sub-opposite (not apically emarginate); sessile to sub-sessile; markedly asymmetrical to symmetrical or nearly so; more or less pinnately veined, with a predominant midrib (which is more or less displaced towards their inner sides); without a continuous marginal nerve. Stipules absent or early caducous or very inconspicuous in mature leaves (caducous); membranous; not connate (the margins valvate, joined only by hairs). Stipels absent.
Inflorescence and floral morphology. The inflorescences axillary (at the terminal nodes); branched; of racemose units; panicles (in compound racemes, the flowers almost sessile in a series of clusters). Bracts glabrous within. Bracteoles present; relatively large and enclosing the flower buds; persistent beyond anthesis; basally connate.
The flowers hermaphrodite and unisexual (some male, others bisexual); not pentamerous throughout; departing from pentamery in the calyx, in the corolla, and in the androecium. Hypanthium present (but very short), or absent, the androecium hypogynous. The perianth more or less absent (usually), or comprising distinct calyx and corolla, or exclusively sepaline. Calyx 0, or 1 (with only the adaxial member sometimes present); not covering the rest of the flower in bud; very reduced. Corolla obscurely present, or absent; 0, or 1; including greatly reduced members to without greatly reduced members; sometimes inconspicuously monopetalous (usually wanting, but sometimes represented by a single vestigial lateral). Petals sessile; white. The androecium comprising 6–8 members; with united members (the stamens all shortly joined basally); members all more or less equal in length; comprising only fertile stamens. Fertile stamens 6–8. Anthers attached well above the base of the connective; dehiscing longitudinally (without dorsal teeth). Ovary shortly stipitate (both stalk and ovary completely velvety, and the style inserted eccentrically); free. Stigma dilated (more or less mushroom-shaped). Ovules few (1–3).
Fruit, seed and seedling. Fruit a two-valved pod (fairly conspicuously beaked). The mature valves with conspicuous, prominent, raised venation; conspicuous venation predominantly longitudinal (the valves reticulately veined, and with the strong lateral nerve running above the middle of the valve). Seeds not arillate. Cotyledons epigeal (the first seedling leaves opposite).
Species number and distribution. 1 species (I. dunensis). Confined to the central coast of Mozambique.
Tribe. Detarieae; Amherstieae clade of Bruneau et al. (2008).
Miscellaneous. Illustrations: • I. dunensis: Wieringa (1999).
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’.