Annonaceae Juss.

Annonaceae, N. K. B. Robson. Flora Zambesiaca 1:1. 1960

Morphology General Habit

Trees, shrubs, or lianes (rarely rhizomatous shrublets), glabrous or with an indumentum of simple, stellate or lepidote hairs; bark usually smooth and entire, pale grey or buff to brown, the branches often reddish to purple-black with lozenge-shaped striations, pubescent or tomentose (rarely glabrous) when young; pith septate, oil cells present

Morphology Leaves

Leaves alternate in two rows, entire, penninerved, membranous to coriaceous, exstipulate

Morphology Reproductive morphology Flowers

Flowers morphologically terminal (i.e. terminal, supra-axillary, extra-axillary or leaf-opposed) or axillary, solitary or paired to fasciculate or cymose, on the young or old wood, sessile or pedicellate, more rarely pedunculate, actinomorphic, bisexual or more rarely unisexual, often fragrant

Morphology Reproductive morphology Flowers Calyx

Sepals 3 (2), usually valvate in bud, free or ± united

Morphology Reproductive morphology Flowers Corolla

Petals 6 (4) in two equal or ± unequal whorls (more rarely one whorl of 6, 4 or 3), imbricate or valvate (rarely open) in bud, free or ± united at the base, usually alternating with the sepals

Morphology Reproductive morphology Flowers Androecium

Stamens ?, spiral, or 6–12 and whorled (sometimes staminodial) with anthers linear to semi-orbicular, lateral or extrorse (rarely apical); connective usually prolonged beyond the thecae, with the apex truncate, oblique, capitate, convex, conical or acute; filaments usually very short or absent, free, rarely more elongate and united in a cone over the gynoecium (Xylopia)

Morphology Reproductive morphology Flowers Gynoecium

Carpels ?–1 free or united at the base, or completely united to form a 1-locular ovary (Monodora); ovules ?–1: styles free or united, or absent

Morphology Reproductive morphology Fruits

Fruit apocarpous with ripe carpels baccate (fleshy or lignified) or rarely dehiscent, stipitate or sessile, or syncarpous with either aggregated 1-seeded carpels or 1-locular and ?-seeded, Seeds vertical to horizontal, sometimes arillate, with abundant ruminate endosperm; embryo minute

Annonaceae, Hutchinson and Dalziel. Flora of West Tropical Africa 1:1. 1954

Morphology General Habit

Trees, shrubs or climbers, aromatic

Morphology Leaves

Leaves alternate, entire, exstipulate

Morphology Reproductive morphology Flowers

Flowers terminal, leaf-opposed or axillary, solitary or crowded, hermaphrodite or rarely unisexual, mostly trimerous

Morphology Reproductive morphology Flowers Calyx

Sepals 3, rarely 2, separate or united into a 3-lobed calyx, valvate or rarely imbricate, persistent or deciduous

Morphology Reproductive morphology Flowers Corolla

Petals generally 6, in two series, valvate or slightly imbricate, rarely in two series of 2, or the inner series absent

Morphology Reproductive morphology Flowers Androecium

Stamens generally numerous, hypogynous; anther-cells adnate, with the connective often truncate

Morphology Reproductive morphology Flowers Gynoecium

Carpels numerous or rarely few or solitary, free or very rarely united into a 1-celled ovary with parietal placentas; ovules 1 or more

Morphology Reproductive morphology Fruits

Fruiting carpels sessile or stipitate, mostly indehiscent

Morphology Reproductive morphology Seeds

Seed with or without an aril, with copious ruminate endosperm and minute embryo

Milliken, W., Klitgard, B. and Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. http://creativecommons.org/licenses/by/3.0

Morphology General Habit

Trees, shrubs, or very rarely lianas, bark very tough and fibrous and easily torning off in long strips, often with a spicy aroma when cut

Morphology General Indumentum

Indument of vegetative, floral, and fruiting parts composed of simple, stellate, or lepidote hairs, or lacking

Morphology Leaves

Leaves simple, alternate, distichous, very rarely spirally arranged (Tetrameranthus R.E.Fr.),  pinnately veined

Morphology Reproductive morphology Flowers

Flowers axillary or internodal (often leaf-opposed), rarely terminal, single or in rhipidiate inflorescences, rarely in panicles, bracts present, sometimes lacking (a.o. Cymbopetalum Benth.); sepals (2-)3(-4), free or variously connate; petals 6, rarely 3 (e.g. some species of Annona L.) or 8 (Stenanona p.p. and Tetrameranthus), mostly in two 3- merous whorls, free, rarely connate; stamens many, spirally arranged, filaments mostly very short, anthers dithecic, extrorsely and longitudinally dehiscent, sometimes transversely septate (a.o. Xylopia L.) often with an apical, shield-like prolongation of the connective; staminodes rarely present; carpels many, rarely few, with a sessile stigma or apex more or less narrowed into a style, placentation basal or lateral, rarely apical, ovules 1 to many

Morphology Reproductive morphology Fruits

Fruit mostly apocarpous, the carpels (monocarps) usually stipitate, fleshy, indehiscent, sometimes dehiscent (e.g. Anaxagorea St.Hil. and Xylopia), less frequenly fruit pseudosyncarpous (e.g. Duguetia A.St.-Hil.) or syncarpous (e.g. Annona)

Morphology Reproductive morphology Seeds

Seeds 1-many per monocarp, often rather large, with ruminate endosperm, sometimes arillate.

Diagnostic

"Anaxagorea: Neotropical genus which also occurs in tropical Asia. Unique in the family by its explosively dehiscent (2-seeded) monocarps; the seeds can in this way been dispersed up to many meters (7 m) from the mother tree! Annona: Genus also occurring in Africa. Recent molecular and morphological research by H. Rainer (in prep.) has revealed that the genera Rollinia and Raimondia should be merged into Annona. The genus Annona is characterized by having syncarpous fruits (except for some species of the former genus Rollinia). It occurs all over the Neotropics, also in the dry cerrado vegetations of Brazil, where most other genera of Annonaceae are lacking. Cymbopetalum: As the name Cymbo (boat) and petalum (petal) already suggests this genus is characterized by having boat-shaped inner petals (with the margins mostly strongly rolled inwards). Furthermore its flowers are mostly placed on long, pendent, ebracteate pedicels. Duguetia: Recognizable by its indument of stellate to lepidote hairs. The fruits are peudosyncarpous (carpels connate in various degrees). A few species of Duguetia, which were formerly placed in the genus Pachypodanthium Engl. & Diels, occur in W tropical Africa. Fusaea: This small genus of only two species is quite remarkable by relatively large staminodes (placed between the inner petals and stamens) and by a syncarpous fruit. Guatteria: The largest genus in the Neotropics, which is currently under revision in Brazil (A. Lobao), Utrecht (R.H.J. Erkens) and Wageningen (P.J.M. Maas & L.Y.Th. Westra). It is best recognizable by having axillary flowers with a pedicel which has a suprabasal articulation, whereas all other Neotropical genera have a pedicel with basal articulation.It is a nightmare to study this genus in the herbarium, as mostly only ""open flower buds"" are present. In Guatteria the flower starts as a very young closed bud, then they open and the flowers stay open and green for a long period of several weeks. After that the petals start to lengthen, they change from green to yellow, become erect and enclose with their base a so-called pollination chamber. Only then the pollination takes place. In herbarium material there are almost always only open flower buds present, which means that the measurements of ""petals"" are often incorrect. Hornschuchia: A genus restricted to E and SE Brazil. Various species have their flowers arranged in long flagellate inflorescences (a.o. H. bryotrophe Nees). Oxandra: Good characters to distinguish this genus are found in the shortly pedicellate flowers, in which the pedicels are densely covered with various bracts. In many species the apical prolongation of the connective is acute (Oxy (acute) and andros(male)). Porcelia: Genus with very large, many-seeded monocarps, reaching a length of up to 13 cm. Tetrameranthus: Unique within the Neotropical genera of Annonaceae by having spirally arranged leaves and 4-merous flowers. Xylopia: The only genus in the family occurring in the 3 continents, America, Africa, and Asia. The genus is characterized by axillary flowers, in which the outer petals are generally much larger than the inner ones. The monocarps are dehiscent, mostly several-seeded, and the seeds are provided with a distinct aril." Follow link to illustrated key to Neotropical Annonaceae   http://www.kew.org/science/tropamerica/neotropikey/families/annonaceae_illustrated_key.pdf   Key to genera of Neotropical Annonaceae 1.  Leaves spirally arranged; flowers 4(-6)-merous; indument composed of stellate hairs. The Amazon region and French Guiana in the North and the Pacific coast of Colombia in the West — Tetrameranthus 1.  Leaves arranged in two rows along the stem (distichous); flowers 3-merous (very rarely 2-merous); indument of various types (simple, stellate, or scale-like hairs) — 2. 2.  Indumentum composed of stellate or scale-like hairs (well visible with a hand lens); fruit pseudo-syncarpous and carpels strongly coherent, but only partly connate, the lower carpels sterile and often forming a basal collar. From Costa Rica in the North to Bolivia and Paraguay in the South — Duguetia2.  Indumentum composed of simple hairs or lacking (hairs sometimes stellate in Annona, microscopic stellate to furcate hairs occur in Anaxagorea); fruit either apocarpous or syncarpous, but not as above — 3. 3.  Flowers and fruit axillary (sometimes leaf-opposed in Anaxagorea brevipes) or sometimes arising from the trunk (cauliflorous); fruit apocarpous — 4.3.  Flowers and fruit terminal, leaf-opposed, or supra- axillary, rarely arising from the trunk; fruit apocarpous or syncarpous — 22. 4.  Upper leaf surface with impressed midrib — 5.4.  Upper leaf surface with raised midrib — 14. 5.  Petals often thick and fleshy (2-10 mm thick) and covered with microscopic, brownish hairs; monocarps club-shaped, explosively dehiscent, 2-seeded. All over the Neotropics, except for the West Indian islands — Anaxagorea5.  Petals generally much thinner and covered with much larger hairs or glabrous; monocarps never club-shaped, generally globose to ellipsoid, indehiscent, or non-explosively dehiscent, 1-several-seeded — 6. 6.  Pedicels with a supra-basal articulation (a few milimetres above the base of the pedicel). All over the Neotropics — Guatteria6.  Pedicels with a basal articulation — 7. 7.  Sepals 2; petals 4; carpels 1(-2). Mexico — Tridimeris7.  Sepals 3; petals 6; carpels generally numerous — 8. 8.  Monocarps dehiscent, 1-several-seeded; seeds distinctly arillate; young twigs mostly lenticellate; leaves generally small and narrow. All over the Neotropics —  Xylopia 8.  Monocarps indehiscent, 1-several-seeded; aril absent or indistinct; young twigs not lenticellate; leaves mostly much larger and broader — 9. 9.  Monocarps several-seeded — 10.9.  Monocarps 1-seeded — 11. 10.  Petals often maroon, 10-80 x 10-50 mm, distinctly veined; inner petals much shorter than the outer ones; monocarps 1-12. SE USA to S Canada — Asimina 10.  Petals mostly white, 7-23 x 1-3 mm, not veined; petals subequal or inner petals longer than the outer ones; monocarps 1-2. Tropical South America, but mainly Amazonian — Diclinanona 11.  Upper leaf surface with distinctly impressed venation; monocarps long-stipitate (stipes 5-35 mm long); petals 8-12 mm long. Tropical South America, but mainly in NE Brazil — Ephedranthus11.  Upper leaf surface with flat, not or slightly impressed venation; monocarps short- to long-stipitate; petals 4-70 mm long — 12. 12.  Pedicels with 3-6 bracts; stipes of monocarps less than 8 mm long; petals 4-8 mm long; all flowers bisexual. All over the Neotropics — Oxandra12.  Pedicels with 1-2 bracts; stipes of monocarps more than 10 mm long, generally much longer; petals 7-70 mm long; flowers androdioecious (male and bisexual flowers present) — 13. 13.  Pedicels with 1 bract above the articulation; petals 8-21 mm long, spreading and leaving the floral center uncovered; raphe of seeds raised, straight. Western South America — Pseudomalmea13.  Pedicels without a bract above the articulation; petals 10-30 mm long, concave, covering the floral center; raphe of seeds impressed, straight to slightly sinuous. Tropical South America up to Cost Rica in the North — Klarobelia 14.  Petals often fleshy (2-10 mm thick) and covered with microscopic, brownish hairs; innermost stamens staminodial; monocarps club-shaped, explosively dehiscent, 2-seeded. All over the Neotropics, except for the West Indian islands — Anaxagorea14.  Petals generally much thinner and covered with much larger hairs or glabrous; all stamens fertile or outermost stamens staminodial (Fusaea); monocarps globose to ellipsoid, indehiscent or non-explosively dehiscent, 1-several-seeded — 15. 15.  Leaves with distinct marginal vein, almost touching the margin (except in P. espirito-santensis); petals 4-15 mm long. Tropical South America —  Pseudoxandra 15.  Leaves without a marginal vein (except in Oxandra p.p., but then much further removed from the margin); petals 4-35 mm long — 16. 16.  Lower leaf surface glaucous; monocarps transversely ellipsoid, 1-seeded; petals 25-35 mm long. Western part of South America — Ruizodendron16.  Lower leaf surface not glaucous; monocarps ellipsoid to globose, 1-several-seeded; petals 4-20 mm long — 17. 17.  Monocarps 1-2, sessile, 2-4-seeded; petals 4-8.5 mm long, with a small, incurved, tail-like, apical appendage. Tropical South America — Onychopetalum17.  Monocarps generally many more (up to 30), mostly distinctly stipitate, often 1-seeded; petals 2.5-20 mm long, without an apical appendage — 18. 18.  Leaves asymmetrical; petals 2.5-4.5 mm long; monocarps 1-seeded (except in B. pleiosperma), shortly stipitate. Tropical South America — Bocageopsis 18.  Leaves symmetrical; petals mostly > 5 mm long; monocarps 1-several-seeded, mostly distinctly stipitate — 19. 19.  Upper leaf surface with a distinctly grooved midrib. From Costa Rica in the North to Bolivia in the South, eastwards up to the Guianas, and S of the Amazon River — Cremastosperma 19.  Upper leaf surface with a non-grooved midrib — 20. 20.  Leaves with distinctly raised veins on both surfaces; petals 10-15 mm long; seeds 25-30 mm long. Amazonian SW Venezuela and adjacent Brazil ... Pseudephedranthus 20.  Leaves with veins on the upper surface (except for the raised midrib) not or indistinctly raised; petals 4-10 mm long; seeds 8-20 mm long ... 21. 21.  Inflorescences often 1-flowered, the pedicel densely beset with 3-6 bracts; apical prolongation of connective tongue-shaped; monocarps 1-seeded. All over the Neotropics — Oxandra 21.  Inflorescences often branched, if 1-flowered, the pedicel not densely beset with bracts; apical prolongation of connective discoid; monocarps 1-several-seeded. From Mexico (Oaxaca) in the North to Bolivia, N Paraguay, and S Brazil in the South ... Unonopsis 22.  Bracts absent — 23.22.  Bracts present — 29. 23.  Flowers pendent on long (40-60 mm) pedicels; inner petals boat-shaped. All over the Neotropics, except for the West Indian islands — Cymbopetalum23.  Flowers non-pendent and pedicels much shorter; inner petals not boat-shaped — 24. 24.  Leaves asymmetrical; monocarps 20-90 x 30-40 mm, wall 2.5-4 mm thick. From Costa Rica in the North through Western South America to Bolivia, and SE Brazil — Porcelia24.  Leaves symmetrical; monocarps smaller, wall thinner — 25. 25.  Petals basally connate — 26.25.  Petals free — 27. 26.  Petals basally connate into a 2-4 mm long tube; monocarps dehiscent, falciform, yellow or orange; arilfleshy, 2-lobed. Tropical South America — Cardiopetalum26.  Petals free; monocarps indehiscent, fusiform to linear, green; arilfibrous. Western South America — Froesiodendron 27.  Leaves tri-plinerved at the base; monocarps 3-9; flower buds globose; stamens c. 40. Tropical South America, lacking in the central Amazon basin — Trigynaea 27.  Leaves not tri-plinerved at the base; monocarps 1-3; flower buds globose or conical; stamens < 20. E and SE Brazil — 28. 28.  Flower buds conical; petals linear, recurved to patent; calyx cup-shaped, without distinct lobes; flowers solitary or in many-flowered inflorescences; inflorescences often flagellate and produced from the main stem. E and SE Brazil — Hornschuchia 28.  Flower buds globose; petals ovate to elliptic, erect; calyx distinctly 3-lobed; flowers solitary. E and SE Brazil — Bocagea 29.  Upper leaf surface with raised midrib — 30.29.  Upper leaf surface with impressed midrib — 31. 30.  Fruit apocarpous, the monocarps distinctly stipitate; seeds pitted; sepals < 5 mm long; base of inner petals with food bodies. From Mexico in the North to Peru in the South — Mosannona 30.  Fruit pseudo-syncarpous, the carpels strongly coherent; seeds smooth; sepals > 9 mm long; petals without food bodies. Amazonian Brazil (Upper Rio Negro) — Duckeanthus 31.  Flowers winged; fruit syncarpous (very rarely apocarpous). All over the Neotropics. — Annona p.p. 31.  Flowers not winged; fruit apocarpous or syncarpous — 32. 32.  Outermost stamens staminodial; fruit syncarpous and provided with an almost woody basal collar. Tropical South America ... Fusaea 32.  All stamens fertile; fruit apocarpous or syncarpous, but then without a basal collar — 33. 33.  Fruit syncarpous, each carpel 1-seeded; petals often thick and fleshy. All over the Neotropics — Annona 33.  Fruit apocarpous, each monocarp 1-several-seeded; petals thin — 34. 34.  Pedicels often provided with 1 leafy bract. Mexico and Central America and adjacent N Colombia — Desmopsis34.  Pedicels without leafy bracts — 35. 35.  Monocarps 1-seeded; petals yellow to cream, margins ciliate. From Panama in the North to Peru in the South, also 1 species in SE Brazil (Bahia) — Malmea35.  Monocarps 1-several-seeded; petals red, purple, brown, or rarely cream, not ciliate — 36. 36.  Petals distinctly veined, length-width ratio 2-5; flowers often with a fetid scent; monocarps 13-100 mm long; seeds with lamellate rumination. Mexico and Central America — Sapranthus36.  Petals not distinctly veined, length-width ratio 5-20; flowers without a fetid scent; monocarps 10-30 mm long; seeds with spiniform rumination. Mexico, Central America to the Pacific coast of Colombia — Stenanona Key differences from similar families: Annonaceae can hardly be confused with the two other Neotropical families belonging to the order of Magnoliales, namely Magnoliaceae and Myristicaceae by the above mentioned characters of wood and bark: Myristicaceae differ by having a red latex. Magnoliaceae by having large (soon falling) stipules. Distinguishing characters (always present): Vegetatively easily recognizable by its wood showing concentric bands of parenchyma and by its bark, which is very tough and fibrous and can be torn off in long strips. Leaves distichous. Flowers are (in 95% of the cases) 3-merous, consisting of 3 sepals and 6 (much larger) petals. Stamens and free carpels spirally arranged on the receptacle. Endospermruminate. Stamens generally many, mostly with an apical shield-like prolongation of the connective. Fruit mostly apocarpous.

Distribution

All genera are native in the Neotropics. Several species are cultivated all over the Neotropics because of their edible fruits: some species of Annona, a.o. A. muricata L., A. cherimola Miller, A. mucosa Jacq. (the former Rollinia mucosa), and A. reticulata L. Young stems of Annonaceae are often used as fishing rods. All over the Neotropics, in the North even to the USA and S Canada (Asimina Adans.), particularly common in the lowlands.

Note

In a few species of the family the flowers are arranged in a flagellate inflorescence. This occurs in Duguetia, Hornschuchia, Stenanona, and in 1 species of Guatteria. Notes on delimitation: The family of Annonaceae is placed in the order of Magnoliales, together with 2 families which also occur in the Neotropics, namely Myristicaceae and Magnoliaceae. Number of genera: 35 genera: Anaxagorea (21 spp.) Annona (incl. Raimondia Saff. and Rollinia A.St.-Hil.) (200 spp.) Asimina (10 spp.) Bocagea A.St.-Hil. (3 spp.) Bocageopsis R.E.Fr. (4 spp.) Cardiopetalum Schltdl. (3 spp.) Cremastosperma R.E.Fr. (29 spp.) Cymbopetalum (27 spp.) Desmopsis Saff. (17 spp.) Diclinanona Diels (3 spp.) Duckeanthus R.E.Fr. (1 sp.) Duguetia (90 spp.) Ephedranthus S.Moore(10 spp.) Froesiodendron R.E.Fr. (3 spp.) Fusaea Saff.(2 spp.) Guatteria Ruiz & Pav. (incl. Guatteriella R.E.Fr., Guatteriopsis R.E.Fr., and Heteropetalum Benth.) (175 spp.) Hornschuchia Nees (10 spp.) Klarobelia Chatrou(9 spp.) Malmea R.E.Fr. (6 spp.) Mosannona Chatrou (14 spp.) Onychopetalum R.E.Fr. (2 spp.) Oxandra A.Rich. (25 spp.) Porcelia Ruiz & Pav.(6 spp.) Pseudephedranthus Aristeg. (1 sp.) Pseudomalmea Chatrou (3 spp.) Pseudoxandra R.E.Fr. (22 spp.) Ruizodendron R.E.Fr. (1 sp.) Sapranthus Seem. (10 spp.) Stenanona Standl.(13 spp.) Tetrameranthus (6 spp.) Tridimeris Baill. (1 sp.) Trigynaea Schltdl. (8 spp.) Unonopsis R.E.Fr. (49 spp.) Xylopia (40 spp.)

Timothy M. A. Utteridge and Laura V. S. Jennings (2022). Trees of New Guinea. Kew Publishing. Royal Botanic Gardens, Kew

Distribution

The Annonaceae is a large family of around 108 genera with 2400 species and is found predominantly in the understorey and mid-storey of lowland rain forests; in the Old World, the family includes both trees and lianas. The family is well-defined but has several genera that are currently being re-defined including Polyalthia; recent generic changes are reflected here. In New Guinea there are c. 25 genera with approximately 150 species, including many endemic species and the endemic climbing genus Schefferomitra.

Recognition

The family is easily recognised by the finely ridged twigs (often with peeling bark) with the cross section displaying medullary rays in the wood, exstipulate simple and entire leaves, the flowers with the calyx and petals in threes and numerous stamens and carpels; in addition, the fruit is compound made up of numerous monocarps.

Morphology General Habit

Trees, shrubs or climbers, often with typical ‘Myristicaceous’ branching pattern (with branches radiating horizontally from the main vertical axis)

Morphology General

Sap usually absent

Morphology General Indumentum

Hairs where present, simple or stellate

Morphology Twigs

Twigs/branchlets often dark brown-black with a striate surface or smooth green, cut cross section with medullary rays in the wood; inner bark fibrous

Morphology Leaves Stipules

Stipules absent

Morphology Leaves

Leaves simple, alternate, usually distichous, rarely spirally arranged, margins entire; pinnately veined, sometimes with conspicuous looping intramarginal vein; petiole short. Inflorescences or solitary flowers axillary, terminal, opposite the leaves or rami- or cauliflorous

Morphology Reproductive morphology Flowers

Flowers actinomorphic, usually bisexual; sepals and petals arranged in 3 whorls of 3 parts (rarely in 2s), the outer whorls sepaloid, valvate or imbricate in bud, often thick, white to green to yellow to red (often visited by beetles); stamens numerous, spirally arranged, filaments very short and thick, anthers linear; ovary superior, numerous, free or rarely fused

Morphology Reproductive morphology Fruits

Fruit consisting of 1 to several fleshy indehiscent monocarps or syncarpous (introduced Annona)

Morphology Reproductive morphology Seeds

Seeds either many in 1-locular monocarps, or 1-seeded; large with ruminate endosperm.

George R. Proctor (2012). Flora of the Cayman Isands (Second Edition). Royal Botanic Gardens, Kew

Morphology General Habit

Trees or shrubs with alternate, entire leaves; stipules lacking

Morphology Reproductive morphology Flowers

Flowers mostly perfect and 3-parted; sepals usually 3, valvate or imbricate; petals commonly 6 in two series, valvate or imbricate, the inner ones often rudimentary or absent

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens numerous, the anther- cells adnate; carpels numerous (rarely few), generally free, with 1 or more ovules in each cell, in fruit free or united to form a fleshy multiple fruit

Morphology Reproductive morphology Seeds

Seeds with or without an aril, with copious ruminate endosperm and a minute embryo.

Distribution

A pantropical family of about 75 genera or more, and more than 2,000 species, the majority in the Old World.

Annonaceae, B. Verdcourt. Flora of Tropical East Africa. 1971

Morphology General Habit

Trees, shrubs or lianes, less often small shrublets, often aromatic; bark frequently with a very characteristic impressed pattern of small lozenges on the young shoots; indumentum, if present, simple, stellate or scaly

Morphology Leaves

Leaves alternate, distichous, thin to coriaceous, entire, penninerved; stipules absent

Morphology Reproductive morphology Flowers

Flowers borne on young leafy shoots or on the old wood, rarely on underground suckers, terminal or axillary, hermaphrodite or less often unisexual, solitary, paired, cymose or in fascicles, sessile or stalked, regular, very often fleshy or brittle; bracts and bracteoles often present, sometimes closely enveloping the buds

Morphology Reproductive morphology Flowers Calyx

Sepals 2–3, valvate or rarely imbricate, sometimes not enclosing the petals in bud, free or somewhat united, rarely accrescent

Morphology Reproductive morphology Flowers Corolla

Petals 3–6(–12), usually either in 2 whorls of 2–4 or in a single whorl of 3, 4 or 6, valvate, imbricate or rarely open in bud, free or more or less united at the base, usually alternating with the sepals; rarely petals entirely absent

Morphology Reproductive morphology Flowers Androecium

Stamens 6–12 and whorled or numerous and spirally (often tightly) arranged on a convex receptacle to form an incomplete hemisphere; rarely outer stamens subpetaloid; anthers linear to rounded with lateral, extrorse or rarely introrse dehiscence, occasionally transversely locellate; connective usually produced, mostly dilated, truncate, oblique, convex, conical, acute or capitate; filaments usually short and free or less often longer and united into a cone covering the carpels

Morphology Reproductive morphology Flowers Gynoecium

Carpels 1–numerous, free, united at the base or completely united to form a 1-locular ovary; ovules 1–numerous; styles free or united, sometimes flattened but so folded as to appear subcylindrical; stigmas free or rarely united, capitate, oblong or slightly raised or variously folded forming a margin to the style-tissue or radiating, sometimes bifurcating, rarely apparently absent

Morphology Reproductive morphology Fruits

Fruit either consisting of 1–several separate fleshy or somewhat woody indehiscent or rarely dehiscent, sessile or stipitate monocarps, or syncarpous with numerous 1-seeded fruiting carpels or 1-locular and many-seeded

Morphology Reproductive morphology Seeds

Seeds with longest axis in line with longest axis of the monocarp (vertical) or at an angle to it (oblique to horizontal) or irregular, sometimes arillate, with abundant ruminate endosperm; embryo minute