The World Flora Online

Les 6 espèces gabonaises de Simaroubacées ont toutes des feuilles composées imparipennées non stipulées, parfois très grandes (Nothospondias, Pierrodendron). Les folioles des Pierrodendron, Hannoa, Odyendyea sont d'un type très particulier; le limbe est coriace et la nervation, parfois imprimée, est dans tous les cas peu apparente ou même quasi invisible (Odyendyea). Le rachis des feuilles de l'arbuste Quassia africana est ± ailé. Les fleurs sont hermaphrodites ou polygames. Elles se groupent en deux catégories d'après les étamines. C'est un caractère remarquable chez certains genres de Simaroubacées que les filets des étamines sont pourvus à leur base de petites languettes poilues (Odyendyea, Hannoa, Pierrodendron, Quassia, Iridosma). Seul au Gabon le genre Nothospondias fait exception, de même Brucea. Il est donc très facile au Gabon de reconnaître par ce caractère floral une Simaroubacée. Les étamines, aux filets toujours libres, sont en nombre variable: deux fois plus nombreuses que les pétales (8-10, Odyendyea, Hannoa, Quassia, Nothospondias), en nombre égal (4, Brucea), ou plus de 2 fois le nombre des pétales (15-18 Pierrodendron africanum). Le genre Iridosma se singularise avec (7) 8 pétales et 12-13 étamines. Les calices sont toujours petits, cupuliformes, courtement ou à peine lobés. Les fleurs sont 4-mères ou 5-mères. Un caractère générique de différentiation peut se trouver dans la préfloraison des pétales dans le bouton: imbriquée (Odyendyea, Hannoa, Nothospondias), tordue (Pierrodendron, Quassia), valvaire (Iridosma). Pétales libres, soudés à la base d'un disque. Celui-ci est souvent développé en forme de coussin et porte le gynécée. Parfois il est plutôt déprimé en son centre et apparaît annulaire (Hannoa, Pierrodendron). Les Simaroubacées se divisent fondamentalement en deux groupes selon que les carpelles sont soudés ou non. Dans le cas le plus fréquent, il y a 4-5 carpelles libres, mais unis dans le bouton jusqu'à donner l'apparence d'être soudés. Ils donnent naissance à des fruits apocarpiques qui, par avortement des carpelles, ont souvent l'aspect de fruits simples résultant du développement d'un seul des 4-5 carpelles. Chez le seul Harrisonia abyssinica, qui pourrait se rencontrer au Gabon, les carpelles sont soudés entre eux. Si les carpelles sont libres, les 4-5 styles sont cependant soudés ou au moins agglutinés, et ressemblent ainsi à un style commun. Les carpelles sont uniovulés. Les fruits (méricarpes) sont des drupes, parfois grosses (Odyendyea, Pierrodendron). Les écorces sont amères et sont quelquefois utilisées comme fébrifuges (Quassia amara introduit, Q. africana). Les bois des deux seules espèces de grands arbres sont blancs et tendres (Hannoa Klaineana, Odyendea gabonensis).

Arbres , arbustes, suffrutex ou herbes, parfois aiguillonnés.'Feuilles'sans stipules, alternes, pari- ou imparipennées; folioles souvent coriaces; pétiole et rachis souvent canaliculés ou subailés.'Inflorescences'généralement paniculées.'Fleurs'☿, ♂♀ ou polygames, 3-7-mères; calice à lobes ± soudés; corolle à pétales libres, imbriqués ou valvaires; étamines (1)4-18, à filets munis généralement à la base d'une écaille à bord pubescent; disque présent, charnu, parfois soudé à l'ovaire, à 2-5 carpelles libres ou soudés, 1-2 ovules par loge; styles libres ou soudés.'Fruits drupacés ou capsulaires, charnus ou coriaces.\n\t\t\tFamille comprenant 29 genres des régions chaudes et tempérées; au Congo belge, 6 genres, 12 espèces et 1 variété.\n\t\t\tLes'Irvingieae ont été traitées comme famille indépendante.

Seeds with or without endosperm; embryo straight or curved Fruit usually indehiscent, dry or drupaceous Ovary 2–5-lobed, 1–5-celled, or carpels quite separate; styles 2–5; ovules usually solitary, rarely 2 or more, axile Trees or shrubs, sometimes with bitter bark, rarely spiny Flowers small, unisexual or polygamous, actinomorphic Leaves alternate or rarely opposite, imparipinnate, rarely simple, not or very rarely gland-dotted; stipules absent Calyx-lobes 3–5 Petals 3–5, imbricate or valvate, rarely absent, free or united into a tube Disk present Stamens inserted at the base of the disk, equal or double the number of the petals, rarely more numerous, free, sometimes with a scale at the base; anthers 2-celled, opening lengthwise Fruit usually indehiscent, dry or drupaceous Ovary 2–5-lobed, 1–5-celled, or carpels quite separate; styles 2–5; ovules usually solitary, rarely 2 or more, axile Trees or shrubs, sometimes with bitter bark, rarely spiny Flowers small, unisexual or polygamous, actinomorphic Leaves alternate or rarely opposite, imparipinnate, rarely simple, not or very rarely gland-dotted; stipules absent Calyx-lobes 3–5 Petals 3–5, imbricate or valvate, rarely absent, free or united into a tube Disk present Stamens inserted at the base of the disk, equal or double the number of the petals, rarely more numerous, free, sometimes with a scale at the base; anthers 2-celled, opening lengthwise

Stamens 4–10 (18), rarely ? (not in our area), free, sometimes with a scale adnate at the base of the filament Fruit a berry, or of separate drupaceous mericarps or dry angled mericarps suspended from a central carpophore Ovary subentire or rarely (2) 4–5-lobed, (1) 2–5-locular; loculi 1-ovulate or rarely 2-ovulate, or sometimes with 2–5 free carpels; styles (2) 4–5, free or variously united Disk annular, cupular, or sometimes fused with the ovary, rarely absent Petals (3) 4–5 (9), imbricate or valvate, very rarely united in a tube (not in our area), very rarely absent (not in our area) Trees, shrubs or shrublets, occasionally ± sarmentose, sometimes spiny and with pubescence of simple, sometimes glandular hairs Calyx 2–5-lobed, often very deeply so Flowers bisexual, unisexual or polygamous Inflorescences paniculate, bracteate (in our area) Leaves alternate (at least in our area), pinnate or sometimes simple, exstipulate Fruit a berry, or of separate drupaceous mericarps or dry angled mericarps suspended from a central carpophore Ovary subentire or rarely (2) 4–5-lobed, (1) 2–5-locular; loculi 1-ovulate or rarely 2-ovulate, or sometimes with 2–5 free carpels; styles (2) 4–5, free or variously united Disk annular, cupular, or sometimes fused with the ovary, rarely absent Petals (3) 4–5 (9), imbricate or valvate, very rarely united in a tube (not in our area), very rarely absent (not in our area) Trees, shrubs or shrublets, occasionally ± sarmentose, sometimes spiny and with pubescence of simple, sometimes glandular hairs Calyx 2–5-lobed, often very deeply so Flowers bisexual, unisexual or polygamous Inflorescences paniculate, bracteate (in our area) Leaves alternate (at least in our area), pinnate or sometimes simple, exstipulate

Fls small, regular, hypogynous, often unisexual; pet most commonly 5; stamens twice as many as the pet, or as many as and alternate with the pet, the filaments often with a ventral appendage near the base; nectary-disk intrastaminal, sometimes modified into a gynophore; ovary of 2–5 weakly to firmly united carpels, with distinct styles or a single common style, or seldom the carpels distinct; ovules 1 (2) per carpel, apical and pendulous to basal and ascending-erect, usually epitropous; fr usually a capsule or samara, often schizocarpic; embryo oily, with 2 large, expanded cotyledons; endosperm wanting; trees or shrubs with very bitter bark, wood, and seeds, the lvs alternate, usually exstipulate and pinnately compound. 25/150, mostly of warm regions.

Trees or shrubs usually with bitter bark. Leaves alternate, sometimes opposite, pinnate to unifoliolate or rarely simple; stipules present or absent. Inflorescences axillary, racemose, paniculate, cymose, rarely spicate. Flowers generally small, bisexual or unisexual (andromonoecious, functionally dioecious, or distinctly dioecious), often with rudiments of opposite sex, actinomorphic. Calyx of 4 or 5(-8) sepals, imbricate or valvate. Petals usually 4 or 5(-8), free, imbricate or valvate. Stamens same number as petals and alternate with them, or 2 × as many as petals (or more); filaments free, base often with an appendage; anthers oblong, versatile, bicelled, with a longitudinal slit. Disk usually present, sometimes a gynophore or androgynophore. Gynoecium weakly united at base, or virtually free, usually 2-5-carpellate; ovary superior, with axile placentation; ovules 1 or 2 per locule, apical or basal; style connate or free; stigmas 2-5. Fruit a "drupe" or "samara," actually 1-5 fruitlike monocarps produced per flower, each a druparium or a samarium; endosperm present or absent; embryo straight or curved, with thick cotyledons.

Seed with little or no endosperm Ovary globose or 2–5(–6+)-lobed, 2–5(–6+)-locular with 1(–2) ovules per locule, or with free carpels; styles (2–)4–8, free or variously connate Disc annular, pulviniform, cupular or sometimes inconspicuous (at least in dried specimens) Trees or shrubs, occasionally scandent, sometimes spiny, usually containing bitter substances; pubescence usually simple, sometimes glandular Inflorescences paniculate, racemose or cymose Leaves spirally arranged, pinnate or simple, exstipulate or with stipular spines (Harrisonia) Calyx of 3–5(–6) sepals nearly always partly united, valvate to slightly imbricate Flowers bisexual, unisexual or polygamous Stamens 4–10, inserted at the base of a disc, free, sometimes with a scale attached at the base of the filament Petals 3–5(–9), rarely absent (not in Flora area), usually free, imbricate or valvate Fruit a berry or composed of drupaceous mericarps or dry mericarps attached to a central carpophore Ovary globose or 2–5(–6+)-lobed, 2–5(–6+)-locular with 1(–2) ovules per locule, or with free carpels; styles (2–)4–8, free or variously connate Disc annular, pulviniform, cupular or sometimes inconspicuous (at least in dried specimens) Trees or shrubs, occasionally scandent, sometimes spiny, usually containing bitter substances; pubescence usually simple, sometimes glandular Inflorescences paniculate, racemose or cymose Leaves spirally arranged, pinnate or simple, exstipulate or with stipular spines (Harrisonia) Calyx of 3–5(–6) sepals nearly always partly united, valvate to slightly imbricate Flowers bisexual, unisexual or polygamous Stamens 4–10, inserted at the base of a disc, free, sometimes with a scale attached at the base of the filament Petals 3–5(–9), rarely absent (not in Flora area), usually free, imbricate or valvate Fruit a berry or composed of drupaceous mericarps or dry mericarps attached to a central carpophore