Rutaceae Juss.

Rutaceae, F. A. Mendoça. Flora Zambesiaca 2:1. 1963

Morphology General Habit

Trees or shrubs, rarely suffrutices or perennial herbs, with odoriferous oil-glands, sometimes armed with prickles or spines

Morphology Leaves

Leaves simple or pinnate or (1) 3-foliolate; lamina dotted with pellucid glands all over the surface or on the margin only

Morphology Reproductive morphology Inflorescences

Inflorescences of panicles, racemes, cymose clusters or glomerules, terminal, axillary, or terminal and axillary, sometimes also on older leafless branches

Morphology Reproductive morphology Flowers

Flowers (2–3) 4–5-merous, actinomorphic, bisexual or unisexual by abortion and dioecious

Morphology Reproductive morphology Flowers Calyx

Sepals free or united, usually imbricate

Morphology Reproductive morphology Flowers Corolla

Petals free, imbricate or rarely valvate

Morphology Reproductive morphology Flowers Androecium

Stamens as many as or twice as many as the petals, free or rarely numerous and in phalanges, inserted at the base of a disk; anthers 2-lobed at the base, sometimes with an apical gland; staminodes well-developed or vestigial or absent

Morphology Reproductive morphology Flowers Gynoecium

Ovary vestigial in the male flowers, in the female flowers of a single carpel which is sessile, subsessile or stipitate, 1-locular and 2-ovulate, or of 2–5 (7) carpels united for their full length and sessile or on a short or long gynophore, or slightly united at the base and by the stigma (otherwise free), each carpel 1-locular and 2-ovulate, or rarely 1–? ovulate; style long or short or absent, terminal or lateral; stigma capitate or discoid, ± deeply lobed

Morphology Reproductive morphology Fruits

Fruit baccate or drupaceous, 1–4-locular (1–3 loculi abortive), with 1-seeded loculi, or a 5-locular capsule with 2-seeded loculi, or 2-locular with 5–6-seeded loculi, or rarely a 1-seeded follicle

Morphology Reproductive morphology Seeds

Seeds oblong, reniform or rounded; endosperm present or absent

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 or shrubs (these many- to few-branched), rarely sub -shrubs or herbs (Apocaulon R. Cowan from Peru and Ertela Adans. from Brazil), usually evergreen, very rarely deciduous, some aculeate (Zanthoxylum L. spp.) or armed with thorns (Raulinoa R. Cowan, some Citrus L.), all organs with glandular dots containing ethereal aromatic oil; stipules lacking

Morphology Leaves

Leaves alternate, opposite or whorled, 1-3-foliolate, pinnately (including 2- pinnate in Dictyoloma A. Juss.) or palmately compound, rarely simple; lamina usually with the ethereal oil glands visible as pellucid dots

Morphology Reproductive morphology Inflorescences

Inflorescences terminal or axially, very rarely cauliflorous, in racemes, cymes, thyrses (including diplo-thyrses), spikes, or other types

Morphology Reproductive morphology Flowers

Flowers (4-)5- merous, actinomorphic or zygomorphic (mostly in Galipeinae), bisexual or rarely unisexual by abortion (plants dioecious or monoecius); sepals with free or connate lobes, aestivation imbricate or valvate; petals free or connate (Gallipeinae), aestivation imbricate, rarely valvate (e.g. Hortia Vand.).

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens usually as many as petals in Neotropical groups and alternating with the corolla lobes, or reduced to only 2 (together with 3-5 staminodes) or 3 (with 2 staminodes) functional stamens in Galipeinae, the filaments usually free or rarely connate, sometimes adnate to the corolla, some with basal appendages, dehiscence longitudinal; intrastaminal disc usually present, rarely absent (e.g. Adiscanthus Ducke), entire or rarely reduced to a unilateral incomplete disc (Ertela)

Morphology Reproductive morphology Flowers Gynoecium

Gynoecium composed of (1-2-)4-5 carpels in Neotropical groups, free to fully syncarpic to different degrees, locules as many as carpels; ovary (-ies) superior, placentation axial or parietal in the apocarpic ovaries, ovules per locule usually (1-)2 in Neotropical groups (4-5 in Dictyoloma), superposed or collateral

Morphology Reproductive morphology Fruits

Fruits capsules or schizocarps with 1-5 dehiscent or indehiscent (Pitavia Molina) mericarps, or samaras (e.g. Balfourodendron Méllo ex Oliv., Spathelia L.), samaroids (Helietta Tul.), drupes or berries (Hortia, cultivated Citrus and allies),  the capsules and dehiscent mericarps often with a detaching endocarp ejecting  the seeds when mature

Morphology Reproductive morphology Seeds

Seeds 1-2 to many per carpel; endosperm present (copious or scarce) or absent; cotyledons straight or curved, fleshy or thin and leaf-like, these sometimes folded.

Note

Notes on delimitation: The division of the family Rutaceae in seven subfamilies (Aurantioideae, Dictyolomatoideae, Flindersioideae, Rhabdendroideae, Rutoideae, Spathelioideae, and Toddalioideae) by Engler (1931) was based mainly on morphological characteristics such as degree of connation and number of carpels, fruit characteristics (e.g. dehiscent vs. indehiscent, fleshy or dry, winged or not) and histology of the glands with ethereal aromatic oil. Recent analyses using molecular, chromosomal, and phytochemical evidence have showed Aurantioideae as a monophyletic group, but not Rutoideae, Toddalioideae and Flindersioideae, and these groups must therefore be re-circumscribed. The monogeneric Spathelioideae (Spathelia) and Dictyolomatoideae (Dictyoloma) are part of a larger clade containing African and European genera such as Bottegoa Chiov., Cedrelopsis Baill., Cneorum L., Harrisonia R. Br. ex A. Juss. and Ptaeroxylon Ecklon. & Zeyher. in a re-circumscribed and expanded Spathelioideae (see Chase et al. 1999 and Groppo et al. 2008 for a more detailed discussion). Some Neotropical genera such as Conchocarpus Mikan and Esenbeckia Kunth appear not to be monophyletic, and studies treating their circumscriptions are currently underway. "Rutaceae are best known by the exotic genus Citrus, because of its commercially consumed fruits. Other groups of the same subfamily of Citrus (Aurantioideae, see discussion above) are commonly cultivated as ornamentals in America, including species of Atalantia, Clausena, Murraya, and Swinglea. Other extra-American cultivated genera are Dictamnus, Phellodendron, and Ruta. Native species are used as commercial timbers, such as Euxylophoraparaensis Huber (""pau-amarelo""), Balfourodendronriedelianum (Engl.) Engl. (""pau-marfim""), both from Brazil, and Zanthoxylumflavum Vahl (""West Indian silkwood""). Species of Pilocarpus (the ""jaborandis"") are sources of the alkaloid pilocarpine, used to treat glaucoma: one of the species, P. microphyllus Stapf ex Wardlew. is commercially cultivated in Brazil. The bark of some species of Angostura, Galipea and Hortia are used to treat fevers. Casimiroa edulis La Llave & Lex. (""zapote blanco"", ""white-zapote"") is cultivated for its edible fruits in Central America."

Distribution

About  160 genera and 1,900 species of Rutaceae were recognised by Groppo et al. (2008), of which 48 genera and 350 species occur in the Neotropics (Kallunki 2004), 44-50 of these species belong to the genus Conchocarpus (Galipeinae). Rutaceae is widely distributed in subtropical and tropical or less frequently in temperate regions of the world. In the Neotropics the family is more diverse in the understorey of moist forests, especially in Brazilian Atlantic rain forests (Galipeinae), but species of this group can also be found in drier areas (e.g. Casimiroa, Zanthoxylum, Balfourodendron and Helietta). Cneoridium, Thamnosma, and some Zanthoxylum, Ptelea and Choisya species occur in desertic or temperate areas in North America (Mexico); and the monospecific Pitavia occurs in temperate areas in Chile.Adiscanthus Ducke - native, 1 species, Amazon (Peru, Venezuela, Brasil). Almeidea A. St-Hil. - native, 5 species, Brazil and Bolivia. Amyris P. Browne - native, c. 40 species, USA (Texas, Florida), Mexico, Central America (including West Indies) to Peru and Brazil.    Andreadoxa Kallunki - native, 1 species, Brazil (Bahia). Angostura Roem. & Schultes - native, 8 species, Central America (Nicaragua) and southwards to Venezuela, Southern Brazil and Bolivia. Apocaulon R. Cowan - native, 1 species, Venezuela (Guyanan Shield). Balfourodendron Méllo ex Oliv. - native, 2 species, Northeastern to Southern Brazil, Paraguay and Northeastern Argentina. Casimiroa Llave & Lex. - native, c. 10 species, North America (Texas-USA, Mexico) to Costa Rica. Choisya Kunth - native, 7 species, Mexico and Southern USA (Arizona). Citrus L., Murraya Koenig ex L.and other allies (subfamily Aurantioideae) - introduced from Asia, cultivated as ornamentals or because of their edible fruits (Citrus). Cneoridium Hook.f. - native, 1 species, USA (California). Conchocarpus Mikan - native, 46-50 species, Central America (Nicaragua) and southwards to Bolivia and Southeastern Brazil. Decagonocarpus Engl. - native, 2 species, Venezuela (Guyanan Shield), Northern Brazil, Colombia. Decatropsis Hook.f. - native, 2 species, Central America (Guatemala, Honduras), Mexico. Decazyx Pittier & S.F. Blake - native, 2 species, Central America (Costa Rica, Guatemala, Honduras), Mexico. Desmotes Kallunki - native, 1 species, Central America (Panama, endemic to Coiba Island). Dictamnus L. - introduced from the Old World, cultivated. Dictyoloma A. Juss. - native, 1 species, Peru, Bolivia and Brazil.  Ertela Adans. - native, 2 species, Mexico through Northern and Central South America (Brazil, Peru, Bolivia).  Erythrochiton Nees & Mart. - native, 7 species, Central America (Costa Rica) across Northern South America and South to Bolivia and Brazil. Esenbeckia Kunth - native, 28 species, Mexico to Northeastern Argentina. Euxylophora Huber. - native, 1 species, Brazil (Pará). Galipea Aubl. - native, c. 17 species, Cuba and from Guatemala southwards through the Neotropics. Helietta Tul. - native, 8 species, Mexico and USA (Texas), Central America (Cuba), Northern South America, Peru, Paraguay, Brazil and Northern Argentina. Hortia Vand. - native, 10 species, Panama, Northern South America to São Paulo state (Brazil, Atlantic rain forest); one species in Brazilian and Bolivian savannahs). Leptothyrsa Hook.f. - native, 1 species, Amazon (Brazil, Colombia, Peru). Lubaria Pittier - native, 1 species,  Costa Rica, Venezuela. Megastigma Hook.f. - native, 1-2 species, Central America (Guatemala), Mexico. Metrodorea - native, 5 species, Surinam through Brazil to Bolivia. Naudinia Planch. & Linden - native, 1 species, Colombia. Neoraputia Emmerich - native, c. 8 species, French Guiana, Peru, Venezuela, Brazil (Amazon and Atlantic rain forests). Nycticalanthus Ducke - native, 1 species, Brazil (Central Amazon). Plethadenia Urb. - native, 2 species, Central America (Cuba and Hispaniola). Peltostigma Walp. - native, 3 species, Central America (West Indian Islands, Guatemala, Nicaragua), Mexico and Peru. Phellodendron Rupr. - Old World, cultivated.  Pilocarpus Vahl. - native, 16 species, Mexico, Central America (including the Antilles) to Argentina. Pitavia Molina - native, 1 species, Southern Chile. Polyaster Hook.f. - native, 1 species, Mexico. Ptelea L. (include Taravalia Greene) - native, 1-6 species, North America (Mexico and USA). Raputia Aubl. - native, 10 species, Northern South America. Raputiarana Emmerich - native, 1 species, Brazil (Amazonia). Rauia Nees & Mart. - native, c. 7-8 species, Brazil (Atlantic Rain Forest). Raulinoa R. Cowan - native, 1 species, Brazil (restricted to Santa Catarina). Ravenia Vell. Conc. - native, c. 14 species, Central America (Greater Antilles, Trinidad), from Honduras to Brazil and Peru.  Raveniopsis Gleason - native, 19 species, Venezuela (Guiana Shield), Northern Brazil. Ruta L. - Old world, cultivated. Rutaneblina Steyerm. & Luteyn. - native, 1 species, Venezuela (Guyanan Shield). Sigmatanthus Huber ex Emmerich - native, 1 species, Brazil (Northeast, Pará to Ceará). Spathelia L. - native, c. 15 species, Mexico, Central America (Bahamas, Cuba, Jamaica) Northern South America to Brazil (Rondonia and Mato Grosso states). Spiranthera A. St-Hil. - native, 5 species, Northern South America, Peru, Bolivia to Brazil (savannah and Atlantic forest). Stauranthus Liebm. - native, 1-2 species, Mexico to Panama. Thamnosma Torrey & Frémont - native, 8-9 species (3-4 in America), Northeastern Africa, Southern USA and Northern Mexico. Ticorea Aubl. - native, 5 species, throughout the Amazon in the Guianas, Brazil, Ecuador, Perua and Bolivia. Toxosiphon Baill - native, 4 species, Southern Mexico south to Panama, Ecuador, Northern Bolivia and Brazil. Zanthoxylum L. - native, c. 180-200 species, (sub) tropics worldwide, c. 72 in America, widespread.

Diagnostic

Distinguishing characters (always present): Leaf lamina aromatic, usually with ethereal oil glands visible as pellucid dots. Stipules absent. Superiorovary. Trees or shrubs, less often sub -shrubs or herbs. Flowers usually actinomorphic and small, usually white or cream. Intrastaminal disc usually present. Fruits capsules or schizocarps with 1-5 dehiscent mericarps, often with a detaching endocarp that ejects the seeds when mature, a mechanism analogous to most Euphorbiaceae. In many Neotropical Rutaceae (all Galipeinae, Pilocarpus, Metrodorea, Raulinoa, Esenbeckia, Plethadenia, Peltostigma and Zanthoxylum) the fruits are capsules or schizocarps with 1-5 dehiscent mericarps, many times with a detaching endocarp that ejects the seeds when mature, a mechanism analogous to that found in most Euphorbiaceae. Tribe Galipeinae, the most diverse group of the Neotropics with 28 genera and c. 130 species, includes species with mostly zygomorphic flowers, a more or less tubular corolla, the filaments adnate to the corolla tube, and 2 (rather than 5) stamens and 3 staminodes. Zanthoxylum consists of species with pinnate leaves, frequently with aculeate (spiney) bark and (sometimes) leaves. Flowers are unisexual (in dioecious species). Metrodorea, Esenbeckia, Helietta, Balfourodendron, Pilocarpus and Raulinoa are trees or shrubs with 1-3-foliolate (rarely simple or pinnate - some Pilocarpus) leaves. They have small, actimorphic flowers, usually creamy white (some species with wine-red flowers in Pilocarpus and Metrodorea). Raulinoa (endemic to Santa Catarina state, Brazil) are armed with thorns. Pilocarpus have racemose inflorescences, while the remaining genera have compound inflorescences (panicles or thyrses). Metrodorea and Esenbeckia have capsular fruits. Metrodorea have opposite leaves (like in some species of Esenbeckia) with the sheaths of the opposite leaves joined at base with the upper part cucullate, protecting the apical branch bud. In Balfourodendron and Helietta the fruits are indehiscent and winged. Casimiroa (Mexico and some parts of Central America) and Hortia (South America and Panama, most species in the Amazon) have baccate fruits. Casimiroa have palmately compound leaves and small, creamy-white flowers. Hortia have simple, usually large leaves (30-120 cm long) and pink flowers in large inflorescences. Dictyoloma and Spathelia have small flowers with staminal filaments with hairy basal appendages as do some Simaroubaceae. Dictyoloma have 2-pinnate leaves and winged seeds. Spathelia are monopodial trees from the Amazon and Central America with large, 1-pinnate leaves crowded at the apex of the trunk as palms, and with samaroid fruits. Key differences from similar families: Rutaceae can be confused with other families of Sapindales such as Meliaceae, Simaroubaceae or Sapindaceae because of the compound leaves, but they can be readily distinguished from these by the aromatic leaves with pellucid dots, which are scattered throughout the lamina or restricted to the margins. There are several species of few-branched (frequently monopodial) shrubs from understorey of forested areas in Brazil and other countries with simple, large and alternate leaves that can be confused with other groups such as Clavija (Theophrastaceae), Pouteria (Sapotaceae) and member of the  Euphorbiaceae.

Rutaceae, J.O. Kokwaro (University of Nairobi). Flora of Tropical East Africa. 1982

Morphology General Habit

Trees or shrubs, rarely suffrutices or perennial herbs, sometimes armed with spines or prickles

Morphology Leaves

Leaves simple, trifoliolate, pinnately or palmately compound, spicy-aromatic when crushed; lamina dotted with pellucid glands (at least along the margin)

Morphology Reproductive morphology Inflorescences

Inflorescence variable, but mostly of panicles, racemes or cymose clusters

Morphology Reproductive morphology Flowers

Flowers bisexual or unisexual by abortion and dioecious, actinomorphic A pistillode sometimes present in ? flowers; staminodes sometimes absent in ? flowers

Morphology Reproductive morphology Flowers Calyx

Sepals (2–)4–5, free or united towards the base, usually imbricate in bud

Morphology Reproductive morphology Flowers Corolla

Petals (0–)4(–8), free and usually imbricate

Morphology Reproductive morphology Flowers Androecium

Stamens 3–10(–40), usually as many as or twice as many as the petals; filaments free or united into groups, inserted at the base of a disk; anthers 2-thecous

Morphology Reproductive morphology Flowers Gynoecium

Ovary superior; carpels 1–5(–15) or rarely more, free below or completely united; ovules 1–several in each locule; placentation usually axile; style usually 1; stigma 1, capitate and large

Morphology Reproductive morphology Fruits

Fruit a berry or drupe, 1–4–many-locular with 1–8-seeded locules, or a 5–8-locular capsule with 2–many-seeded locules, rarely 1-seeded follicle

Morphology Reproductive morphology Seeds

Seeds oblong, reniform or rounded; endosperm often absent

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

Distribution

A family of about 160 genera and 1900 species, with an almost cosmopolitan distribution but most diverse in the tropics and subtropics. In New Guinea there are 22 genera, all but one of which (Luvunga Buch.-Ham. ex Wight & Arn.) can be trees and shrubs.

Recognition

Rutaceae are usually trees and shrubs, with alternate or opposite leaves which may be simple (unifoliolate) or compound and which are often aromatic and with pellucid gland dots, the flowers arranged in cymose inflorescences, usually bisexual with the stamens arranged in a ring and an obvious disk. The family has a wide variety of fruit types, including capsules, drupes, berries and hesperidia. Generic limits within Rutaceae have been revised through molecular work and some relationships between genera are still in flux.

Morphology General Habit

Trees and shrubs, sometimes climbers, rarely herbs

Morphology General Prickles

Prickles or spines sometimes present

Morphology Leaves Stipules

Stipules usually absent. Leaves alternate or opposite, simple, unifoliolate or variously compound, often trifoliolate, petioles often pulvinate, rachis often winged, margins entire to serrate, aromatic oils and pellucid gland dots usually present

Morphology Reproductive morphology Inflorescences

Inflorescences terminal or axillary, sometimes ramiflorous, cymose or umbellate

Morphology Reproductive morphology Flowers

Flowers actinomorphic, bisexual, rarely unisexual (Lunasia, Melicope and Zanthoxylum), (3–)4–5(–6)-merous, green, white or cream; calyx lobes free or fused; petals usually free, imbricate or valvate; stamens equal or double the number of petals, sometimes numerous, filaments free, in bundles or fused into a tube, anthers with 2 thecae, dehiscing by longitudal slits; disk usually present, often nectiferous; ovary superior, syncarpous or apocarpous, 4–5 carpellate, each carpel 1-locular, ovules usually 2 per carpel, style 1 per carpel, free or fused

Morphology Reproductive morphology Fruits

Fruit a capsule, schizocarp, drupe, berry, samara or a hespiridium with pulp-vesicles filling the locules

Morphology Reproductive morphology Seeds

Seeds usually 1 per carpel, sometimes winged or hairy.

Rutaceae, Hutchinson and Dalziel. Flora of West Tropical Africa 1:2. 1958

Morphology General Habit

Shrubs or trees, rarely herbs

Morphology Leaves

Leaves simple or compound, mostly gland-dotted; stipules absent

Morphology Reproductive morphology Flowers

Flowers hermaphrodite or unisexual, actinomorphic

Morphology Reproductive morphology Flowers Calyx

Sepals 4–5, imbricate, free or connate

Morphology Reproductive morphology Flowers Corolla

Petals imbricate, rarely valvate, mostly free

Morphology Reproductive morphology Flowers Androecium

Stamens the same or double the number of the petals, rarely numerous, free or rarely united; anthers 2-celled, introrse, opening lengthwise

Morphology Reproductive morphology Flowers Nectaries

Disk usually present within the stamens

Morphology Reproductive morphology Flowers Gynoecium

Ovary superior, syncarpous and often 4–5-celled, or the carpels free (secondary apocarpy); styles free or connate Ovules often 2, superposed

Morphology Reproductive morphology Fruits

Fruit baccate, drupaceous or coriaceous, rarely a capsule

Morphology Reproductive morphology Seeds

Seeds with or without endosperm

Gemma Bramley, Anna Trias-Blasi & Richard Wilford (2023). The Kew Temperate Plant Families Identification Handbook. Kew Publishing Royal Botanic Gardens, Kew

Recognition

Characters of similar families: Anacardiaceae: oily gland dots absent, style excentric, mango or resinous scent to crushed parts, sap present. Sapindaceae: oily gland dots absent, filaments often hairy, free rachis tip in pinnately-compound leaves, no strong scent in crushed parts. Juglandaceae: oily gland dots absent, leaflets with peltate scales on underside, flowers small, often in catkins or spikes. Myrtaceae: ovary inferior, many stamens, leaves simple, usually opposite, leaf margins entire, crushed parts usually scented but not citrus or rank citrus.

Morphology General Habit

Trees, shrubs, some lianas and herbs, occasionally scandent; thorns or spines sometimes present; oil glands present, often visible on leaves, flowers and fruit, ± regular, crushed parts with citrus or rank citrus scent

Morphology General Sap

Sap absent

Morphology Leaves Stipules

Stipules absent

Morphology Leaves

Leaves pinnately (once or more), palmately or trifoliolately compound, sometimes simple or unifoliolate; alternate, opposite or whorled; rachis with or without wings

Morphology Reproductive morphology Inflorescences

Inflorescences variable including cymes, racemes, and panicles, sometimes reduced to single flower, terminal and/or axillary

Morphology Reproductive morphology Flowers

Flowers usually bisexual, sometimes unisexual (monoecious or polygamomonoecious), 3–5-merous; stamens 2–many, arranged in 2 whorls, often in a ring, filaments sometimes thick and fleshy, sometimes flattened, connate at the base or not; disk conspicuous, ovary usually superior, with (1–) 4–5(–to many) locules

Morphology Reproductive morphology Fruits

Fruit variable, including hesperidiums (e.g. Citrus), berries (e.g. Glycosmis), capsules (e.g. Ruta), winged (Ptelea) and drupaceous (e.g. Skimmia)

Morphology Reproductive morphology Seeds

Seeds sometimes black and shiny.

Distribution

161 genera and 2085 species. Mainly tropical and subtropical with a few genera extending into temperate regions.

Note

Trees, shrubs, herbs or lianas. Crushed fresh leaves with citrus or rank citrus scent. Sap absent. Stipules absent. Leaves compound, simple or unifoliolate, alternate or opposite; oily gland dots in leaves, flowers and fruit.

Description Author

Marie Briggs

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

Morphology General Habit

More or less aromatic shrubs or trees, rarely herbs, occasionally scandent, sometimes armed with prickles; leaves alternate or opposite, usually compound, occasionally 1- foliolate or simple, nearly always more or less pellucid-dotted with oil-glands; stipules absent.

Morphology Reproductive morphology Flowers

Flowers perfect, polygamous or dioecious, in axillary or terminal cymes, panicles, racemes, spikes or clusters, rarely solitary, the parts usually in 4s or 5s, rarely 3s

Morphology Reproductive morphology Flowers Calyx

Sepals imbricate or rarely none; petals imbricate or sometimes united

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens as many or twice as many as the petals, rarely more numerous; filaments free or united below, inserted on a hypogenous disc or sometimes adnate to the corolla-tube; anthers 2-celled, often gland- tipped, opening inwardly

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary usually 4–5-locular or the carpels free at the base and united in the styles or stigmas, or altogether free and 1-locular; ovules usually 2 (rarely 4) in each carpel

Morphology Reproductive morphology Fruits

Fruit various, of follicles, or a samara, drupe, or berry; seeds solitary or several in each cell, with or without endosperm.

Distribution

A widely distributed family of about 120 genera and 900 species, chiefly of warm climates, especially numerous in South Africa and Australia.

Ptaeroxylaceae, F. White and B. T. Styles. Flora Zambesiaca 2:2. 1966

Morphology General Habit

Aromatic trees or shrubs with indistinct oil-cavities in the younger parts

Morphology Leaves

Leaves opposite or alternate, pari- or imparipinnate, without stipules

Morphology Reproductive morphology Flowers

Flowers dioecious or polygamous, actinomorphic, 4–5-merous; sepals and petals dissimilar

Morphology Reproductive morphology Flowers Calyx

Sepals small, 4–5, variously connate or almost free, the lobes imbricate or with open aestivation, not concealing the corolla in the bud

Morphology Reproductive morphology Flowers Corolla

Petals 4–5, free, valvate or imbricate

Morphology Reproductive morphology Flowers Androecium

Stamens 4–5, free, alternating with the petals; filaments glabrous

Morphology Reproductive morphology Flowers Nectaries

Disk well-developed, broadly annular, intrastaminal

Morphology Reproductive morphology Flowers Gynoecium

Ovary superior, 2–5-locular, with axile placentation; ovules 1–2 per loculus, descending, with adaxial rhaphe

Morphology Reproductive morphology Fruits

Fruit a capsule, the carpels separating from a persistent central column and dehiscing along the adaxial suture and also near the apex of the abaxial suture

Morphology Reproductive morphology Seeds

Seeds with a long terminal wing