Embryo with 1 cotyledon; leaves almost always with parallel nerves; perianth frequently of two whorls of three partsEmbryo with 2 cotyledons; nerves of the leaves usually branching pinnately and often reticulate; perianth usually in 1 or 2 whorls of 4 or 5 partsFree-floating fresh-water plantsTerrestrial, epiphytic or parasitic, if aquatic then with the roots in the soilLeaves at least 5 cm long, with a large bladder-like petiole (water hyacinth)Leaves not differentiated from the stems; plant thallus-like, to 15 mm long (duckweeds)Fully submerged aquatics or with leaves or flowers floatingTerrestrial or, if aquatic, then with leaves and flowers supported above the water surfacePerianth of 4 parts; stipules axillary (fresh or brackish water)Perianth of 0–3 or 6 parts; stipules 0 or paired or with an auriculate leaf sheathPlant with a short tuberous rhizome; perianth-segment 1, conspicuousPlant with creeping rhizomes or stolons; perianth-segments 0 or 2 or moreFlowers bisexualFlowers unisexualStems and rhizomes covered with long persistent fibres; carpel 1 (marine)Stems and rhizomes not covered with fibres; carpels at least 4, free (fresh water or rarely marine)[link through]Leaves with a distinct blade and petiole and opposite or whorled, or linear and whorled; flowers bracteate; ovary inferior (fresh water or marine)Leaves linear, alternate or subopposite; flowers ebracteate; ovary superiorLeaves with 3 veins, ligulate; pollen filiformLeaves with 1 median vein, eligulate; pollen globoseStems lignified, wiry, bearing conspicuous annular scars; roots branched (marine)Stems herbaceous, with annular scars; roots not branched (marine)[link through]Carpels 3, free, each with 1 style and an expanded stigma (fresh water or marine)Carpel 1, style 1; stigmas 2 or 3, linear (fresh water)[link through]Trees or shrubs with pinnate or palmate leaves (palms)Herbs or rarely shrubs or trees, always with simple leavesPerianth 0 (or in the Poaceae possibly represented by the lodicules)Perianth presentFlowers in dense cylindrical spikes divided into a male region above or below a female regionFlowers solitary or in spikes, racemes, panicles or umbels but, if unisexual, then the sexes not in separate parts of a cylindrical spikeSpike subtended by a large spathe (arums)Spike without a spathe (bulrushes)[link through]Flowers unisexual, in a group surrounded by 4–6 spreading bractsFlowers bisexual or unisexual, each flower or group of fused unisexual flowers subtended and often enclosed by a bract[link through]Fruit membranous, splitting on 1 side to release a smooth translucent seedFruit indehiscentLigule at the base of the leaf blade; leaf base surrounding the stem but the margins very rarely fused (grasses)Ligule usually 0; leaf base usually completely encircling and fused round the stem (sedges)Ovary superior (or somewhat semi-inferior in Haemodoraceae)Ovary inferiorPerianth conspicuous, petal-like; flowers bisexualPerianth membranous, scale-like or of bristles or filaments; flowers bisexual or unisexualAnthers 6Anthers 3Carpels 6 or more, freeCarpels 3, fusedFlowers single and terminal on multi-branched perennial shootsFlowers in umbels, racemes or panicles, if single then not on multi-branched perennial shoots[link through]Flowers in umbels or single terminating long unbranched leafless stems or in Colchicum the base of the flower at ground level during flowering and only carried up when in fruitFlowers in racemes or paniclesBracts at the base of the pedicels at least 3Bracts at the base of the pedicels 1 or 2[link through]Filaments fused to the perianth for at least 20 mmFilaments attached at the base of the perianth[link through][link through]Stems branched; leaves cauline, less than 4 cm longStems simple or, if branched, the leaves either all basal or absent at flowering or the largest leaves more than 5 cm long[link through]Flowers sessile, bisexual, in dense cylindrical spikes at least 30 cm longFlowers pedicellate, if sessile then unisexual and spikes less than 30 cm long[link through]Plants dioecious; leaves basal; perianth lacking nectariesFlowers bisexual; if plants dioecious the leaves along the stems and the perianth segments each with 1 or 2 nectaries[link through]Aerial stem and inflorescence unbranched; flowers always 1 in the axil of each bractAerial stem or inflorescence branched or, if simple, at least some bracts bearing more than 1 flowerLeaves not all basal (always present at flowering)Leaves all basal (not always present at flowering[link through]Flowers yellow; filaments bearded; not forming bulbsFlowers rarely yellow but, if so, filaments not bearded; bulbs[link through][link through]Flowers at least 3 cm longFlowers less than 3 cm longFlowers greenish whiteFlowers red, orange or yellow[link through]Leaves bases laterally flattenedLeaves bases dorsi-ventrally flattened[link through][link through]Fruit a berry; aerial shoot perennial; anthers dehiscing apically (sometimes splitting introrsely later)Fruit a capsule; aerial shoot often lasting only a few months; anther dehiscence introrse[link through]Perianth twisted spirally after floweringPerianth not twisted spirally after floweringFilaments beardedFilaments glabrous[link through]Inflorescence perennial, divaricately branchedInflorescence short-lived, simple or few-branched[link through]Flowers racemoseFlowers corymbose[link through][link through]Anthers dorsifixedAnthers attached at or near their base[link through]Inner three perianth-segments fringedInner three perianth-segments not fringed[link through]Plant climbingPlant erect[link through]Leaves spirally arranged; anthers not coiling into a roll at dehiscence; seeds angularLeaves 2-ranked, perennial; anthers coiling into a roll at dehiscence; seeds flat[link through][link through]Leaves cauline, linear-lanceolate to ovateLeaves basal, linearPerianth of 6 petaloid segmentsPerianth of an outer calyx-like whorl and 3 inner petaloid segments[link through][link through]Perianth of bristles or filaments or fused to form a sac-like structure enclosing the ovary and fruitPerianth of scale-like or petaloid segmentsFlowers unisexual, if bisexual the inflorescence a dense spike at least 30 cm longFlowers bisexual, inflorescence various but if a dense spike then less than 30 cm longLeaves all reduced to scales on rhizomes and aerial stemsLeaves well-developed, linear (in Lomandra juncea stems form simple leaf-like structures), radical or in a rosette terminating massive stemsMonoeciousDioecious or, if flowers bisexual, then in spikes at least 30 cm long[link through]Flowers bisexual, sessile and in dense spikes at least 30 cm longFlowers unisexual, pedicellate or sessile, if sessile and in a dense spike the spike less than 15 cm long[link through][link through]Carpels freeCarpels fusedOvules numerous; inflorescence branched or flowers clustered (most rushes)Ovules 1 in each cell; inflorescence a raceme or spike[link through]Male and female organs combined in a central complex, the column; anther 1 (orchids)Male and female organs separate; anthers 3 or 6Anthers 3Anthers 6–12Water plants with floating leavesTerrestrial plants; if growing in water then leaves erect above the water surfaceInflorescence an umbelInflorescence a cymose or panicle or flowers singleFlowers solitaryFlowers in cymes or paniclesLeaves less than 15 cm long, entireLeaves at least 90 cm long with prickly-dentate margins[link through][link through]Branchlets jointed, ridged; leaves reduced to whorls of scale-like teeth; trees or shrubsStems and leaves not as above; herbaceous or woodyFlowers numerous, enclosed within a hollow fleshy receptacle; trees with latexFlowers exposed or concealed by bracts; only a few with latex[link through]Plants entirely parasitic for their mineral and water requirementsPlants not parasitic or, if partially so, then possessing both normal roots and chlorophyllErect leafless root parasites, lacking chlorophyllParasitic on the aerial parts of the host, posessing chlorophyll (leaves and/or stems green)[link through]Leafless twinersNot twining, usually producing leavesPerianth in whorls of 4 or 5Perianth in whorls of 3[link through][link through]Leaves well-developed; flowers > 5 mm long, generally brightly colouredLeaves reduced to scales along flattened, jointed cladodes; flowers minute, inconspicuous[link through]Flowers unisexual and arranged within a cup formed by connate bracts; a number of male flowers on articulated filaments surrounding a female flower consisting of a stipitate 3-celled ovary (this group of unisexual flowers – a cyathium – may be mistaken for a single bisexual flower)Not as abovePerianth 0 or not consisting of a distinct calyx and corolla (excluding the Asteraceae which are characterised by having a 2-fid style, an inferior ovary and florets in a capitulum)Perianth consisting of a calyx and a corolla whorlFlowers unisexualFlowers (or at least some flowers in each inflorescence) bisexualPerianth 0Perianth presentSmall usually aquatic herbsLarge woody shrubs or trees[link through]Leaves oppositeLeaves alternateLeaves simpleLeaves pinnateDioeciousMonoeciousLeaves opposite or whorledLeaves alternateStipules interpetiolar; ovary inferiorStipules 0 or not interpetiolar; ovary superiorLeaves whorledLeaves opposite or in a half-whorlRootless aquaticsEvergreen shrubs[link through]Leaves compound; climbersLeaves simple[link through]Herbs with stinging hairs; style simple; stamens 4Shrubs or herbs; styles or style-branches 2 or 3; stamens 3–?Ovary with 2–5 cellsOvary with 1 cellOvary cells with 1 ovuleOvary cells with 2 ovulesAnthers 2, arising high on a long-tubular petal-like floral tubeAnthers usually more than 2, not arising on a long-tubular floral tube; perianth herbaceous or scariousLarge trees; fruit a large nut enclosed in a cup below (acorn)Shrubs, herbs or trees; fruit not as above[link through]Stipules ± scarious, united into a sheathStipules free or absentPerianth-tube long and narrow, petal-likePerianth-tube 0 or short and not petal-likeTrees or shrubs; perianth-tube broadly campanulate, petal-likeNot usually trees; perianth not as aboveCarpels ± free; anthers more numerous than the perianth-segmentsCarpels 1 or fused; anthers usually not more numerous than the perianth-segmentsStipules presentStipules 0 or represented by nectariferous glandsPerianth and stamens inserted on a receptacular tube; fruits fleshyReceptacular tube 0; fruit a capsulePerianth closely enveloping the ovary and fruitPerianth not closely enveloping the ovary or fruitCapsule 1-celled and 1-seededCapsule with more than 1 cell and/or more than 1 seedStellate hairs numerousStellate hairs 0, simple hairs presentSeeds carunculate (Chrozophora seeds not carunculate; plant stellate-hairy)Seeds not carunculate; plants glabrous or with simple hairsStigma sessile or almost so; fruit fleshyStigma(s) borne on 1–3 styles; fruit usually dryAnthers 6 to manyAnthers fewer than 6; styles 2–3 or 1 and branchedStyle 1, simpleStyles 3Leaves 2–5 at each nodeLeaves solitary at each node[link through]Perianth scariousPerianth herbaceousSpiny stem-succulents with numerous sepals, petals and stamensNot as aboveLeaves 60–100 cm broad, palmately lobed; flowers and fruits c 1 mm long, redNot as above[link through]Stamens more numerous than perianth-segmentsStamens equal in number to perianth-segments or fewerPerianth 0; stamens 2Not as abovePerianth-segments 4 on a long tube; anthers 8Perianth-segments usually 5–8 (petal-like staminodes sometimes numerous), if 4 then not on a long tube and anthers more than 8, or fused into an operculum when in budCarpels several, freeCarpels 1 or fused[link through]Perianth fused to form an operculum on the budPerianth not fused to form an operculumLeaves oppositeLeaves alternate or apparently whorledOvary 1-celled; leaf bases not dilated and scariousOvary 2- or more-celled, if 1-celled the leaves with dilated scarious stipule-like basesHerbs or small shrubsTreesStyle 1, unbranchedStyles 2 or more or single and deeply dividedStipules membranous and ensheathingStipules 0, minute and caducous or well-developed but not membranous and ensheathingStipules well-developed and persistentStipules 0 or minute and caducousLeaves opposite, if alternate then ovules single in each cellLeaves alternate or apparently whorled; ovules several in each cellOvary entirely or almost entirely inferior; stipules presentOvary superior (or, if rarely inferior or half-inferior either stipules absent or perianth-segments and anthers not 5)Perianth-segments in 2 whorls of 4Perianth-segments 5Inflorescence an umbelInflorescence cymose of flowers in a headLeaves oppositeLeaves alternateStyles or style-branches more numerous than ovary cellsStyles or style-branches equal to ovary cells or fewerLeaves opposite, subulateLeaves alternate (if opposite then flat)Stipules presentStipules 0Stipules scarious, ensheathingStipules paired and not ensheathingLatex producedLatex not producedPerianth scariousPerianth herbaceousStipules 0Stipules present (sometimes small or caducous)Ovary cells 1Ovary cells at least 2Perianth-segments 4 and anthers 2 or 8Perianth-segments 4 and anthers 4, or perianth-segments 3 or 5Either ovary inferior or stigma sessileOvary superior and style developedGlabrous shrubs or treesPubescent annualsPerianth-segments 4Perianth-segments 5Perianth scariousPerianth wholly or partially petaloidStyle 3-branchedStyle simple[link through]Leaves opposite, if alternate then ovules single in each cellLeaves alternate or apparently whorled; ovules several in each cellOvules several in each of 3–5 cellsOvules 1 or 2 in each of 1–3 cellsLeaves compound or deeply dividedLeaves entire or almost soOvary 1-celled with 1 ovuleOvary 3–5-celled, with 2 or more ovules in each cell[link through]Flowers in a capitulum; ovary inferior; style 2-fid; corolla tubularNot as abovePetals (or at least 1 or more of them) free or rarely (Vitaceae) cohering at the apexPetals all fused to form a complete ring or broken on one side onlyOvary inferiorOvary superior or half-inferiorInflorescence an umbelInflorescence a head, racemose or cymose or flowers solitaryTrees with numerous stamensHerbs, climbers or shrubs with 5 stamens[link through]Leaves peltate or digitately lobed or compound, lacking spinesLeaves pinnately lobed or compound, if palmately lobed then spiny[link through]Stipules distinctStipules absentSpines along the branchesSpineless or with branches terminating in spinesWater plants with floating leavesTerrestrial shrubs or trees[link through]Herbaceous; if woody then the ovary conspicuously wingedWoody shrubs or treesStyles 2–4, very short; stigma papillose or plumoseStyle 1, long; stigma capitate or lobedEvergreen shrubs and trees; leaves not lobedDeciduous shrubs; leaves palmately lobed[link through]Styles 2 or moreStyle 1 or stigmas sessileOvary cell 1 (despite carpels sometimes being partly free distally)Ovary cells 2 or more or carpels completely freeLeaves with stalked glands (insectivorous)Leaves without stalked glands[link through]DioeciousFlowers bisexualSepals 2Sepals 4 or 5Flowers bilaterally symmetricalFlowers radially symmetrical[link through]Stamens numerous; leaves with oil-glandsStamens up to 10; leaves without oil-glands[link through]Climbers with tendrilsHerbs, shrubs or trees without tendrilsHerbsShrubs and trees[link through]Leaves opposite or whorledLeaves alternate or radicalCarpels freeCarpels fusedSucculent herbsWoody shrubsOvary cells 2Ovary cells 3–5Evergreen shrub with sessile trifoliolate leaves (appearing as a whorl of 6 simple leaves)Deciduous tree with petiolate simple leaves[link through]Stamens numerousStamens 3 or 4[link through]Stamens 3; leaves stipulateStamens 4 or more; leaves exstipulateCarpels free or ovary deeply lobedCarpels strongly fused (styles fused or free)Spiny woody plantsSpineless; woody or herbaceousShrubs; leaves with conspicuous oil-glandsHerbs or woody; leaves lacking oil-glandsCarpels several to numerous; herbsCarpels 2 or 3; shrubs[link through]Stipules distinct; usually with stellate hairsStipules 0 or minute and caducous; glabrous or with simple hairsLeaves simple; anthers 5Leaves compound; anthers 10[link through]Ovary cell 1, sometimes incompletely dividedOvary completely divided into 2 or more cells or carpels wholly or partly freeOvary half-inferiorOvary superiorOvules along one suture of the ovary onlyOvules along several parietal placentas or basal or on a free central placentaLeaves opposite; flowers radially symmetricalLeaves alternate or radical (if very rarely opposite flowers bilaterally symmetrical)Stamens numerousStamens 4–6[link through][link through]Sepals 2; petals 5Sepals 3 or more; if 2 then petals 4Stamens 5Stamens 4 or 6 or moreLeaves stipulateLeaves exstipulateSepals 2 or 3Sepals 4Stamens 6Stamens 12 or moreShrubs or trees; leaves simpleHerbs; leaves 3–5-foliolate[link through][link through]Petals 3; sepals 5Petals 4–6; sepals 4–6Anthers up to twice as many as the petalsAnthers more than twice as many as the petalsAnthers 2–6Anthers 8–numerousOvary with 2 cellsOvary with 3–5 cellsPerianth and stamens on a tubular floral tubePerianth and stamens arising at the base of the ovarySepals 4; petals 4Sepals 5; petals 5Trees, shrubs or climbers without tendrils; leaves not lobedClimbers with tendrils; leaves deeply lobed[link through]Leaves oppositeLeaves alternate or radicalLeaves simple, exstipulateLeaves compoundLeaves palmate, exstipulateLeaves pinnate or ternate, stipulate[link through]Anthers 4Anthers 5Leaves pinnately compoundLeaves simple[link through][link through]Glabrous annualsVariously hairy or glandular (on leaves and/or calyx) perennials or annuals; if glabrous and eglandular then a dioecious shrub2 or more ovules in each ovary cell1 ovule in each ovary cellLeaves and/or calyx hairy usually with stellate hairsLeaves and calyx glabrous but with immersed glandular dotsWoody glabrous dioecious shrubHerbaceous hairy plants with bisexual flowersOvary with 2 cells; if more than 2 then stamens numerousOvary with 3–6 cells; stamens 8–12Ovules numerous in each cell; anthers dehiscing longitudinallyOvules 1 or 2 in each cellAnthers opening by a terminal pore; glabrous or with simple hairsAnthers dehiscing longitudinally; hairs stellateStamens 8; petals 5Stamens 10 or 12; if 8 then petals 4Herbs; leaves peltateShrubs or trees; leaves compound or lobed[link through]Flowers in paniclesFlowers axillaryHerbaceous or softly woody7; styles separating from the central column when seeds matureWoody shrubs or trees; style simple, not as aboveExstipulateStipulateLeaves 2-lobed or 2-foliolateLeaves simple or 3- or more-foliolateLeaves oppositeLeaves alternateLeaves bi- or tri-pinnate or, if once pinnate, the leaflets less than 1 cm broadLeaves once pinnate with leaflets 2–4 cm broad[link through]Fruit angled, winged or spinyFruit shallowly lobed or tereteStamens numerous, united in a tubeStamens up to 15, freeOvary inferior or half-inferiorOvary superiorFlowers unisexualFlowers bisexualLeaves opposite, with interpetiolar stipules, or leaves whorledLeaves alternate, radical or opposite but stipules 0 or not interpetiolarStamens opposite the petals and of the same numberStamens alternating with and sometimes fewer than the petalsStamens 4 or 5, if 3 then the petals also 3Stamens 1–3; petals 4 or 5Style terminated by a cup-shaped or 2-lipped indusiumStyle simple, notched or 2- or 3-lobedOvary with 1 cellOvary with 2–5 cellsHerbsTrees, shrubs or woody climbersLeaves alternate or radicalLeaves oppositeStamens fewer than the petalsStamens equal or more numerous than the petalsStamens and ovary cells 1 or 2Anthers and/or ovary cells more than 3Leaves radical; small herbsLeaves cauline; trees, shrubs, woody climbers or herbs[link through]Corolla 5-lobed; leaves simpleCorolla 4-lobed, if 5–8-lobed than leaves 3-foliolateFlowers radially symmetricalFlowers bilaterally symmetricalSepals 2; corolla radially symmetrical, split down one sidePerianth characters not as aboveAnthers 3; leaves alternateAnthers 2 or 4; leaves opposite or less often alternate[link through]Style arising between the 4 ovary lobesStyle terminalLeaves compoundLeaves simpleBracteoles at the base of the flowers conspicuous; seeds bearing hooksBracteoles at the bases of the flowers usually 0 or inconspicuous; seeds lacking hooksFruit with a long curved beakFruit not beaked[link through]Fruit spinyFruit not spiny[link through]Fruit a drupe or schizocarp; seeds 1 or 2 in each cellFruit and seeds not as abovePlants densely stellate-hairy, if puberulent or subglabrous then the fruit a drupePlants glabrous or with simple hairs; fruits dryStamens numerousStamens 10 or fewerStamens more conspicuous than the perianth; flowers in dense globular to cylindrical spikes; trees or shrubsStamens less conspicuous than the perianth; flowers not in dense spikes; herbs or shrubsStamens fused to one another; calyx not spurredStamens free of one another; calyx spurredStamens at least twice as numerous as the petalsStamens equal in number to the petalsFlowers radially symmetrical; leaves opposite or whorledFlowers strongly bilaterally symmetrical; leaves usually alternateFlowers to 5 mm longFlowers at least 10 mm longPetals 5Petals 3Stamens 5, united in a tube bearing fleshy appendages (the corona); pollen consolidated into pollen-masses (the pollinia); usually producing copious latexStamens and pollen not as aboveOvary cell 1Ovary cells 2–5Sepals 2Sepals 4 or 5Styles 5Style 1Stems slender, twining; land plantsAerial stems erect or 0, or water plantsStamens opposite the petalsStamens alternating with the petalsLeaves oppositeLeaves alternate or radicalHerbsTrees (mangroves)Leaves alternate; water plants with an open inflorescence of yellow or pink flowersLeaves radical; terrestrial plants with a head of blue flowersLeaves all radical; the small flowers in a dense spike on a naked peduncle; corolla scariousLeaves alternate, opposite or whorled, if radical then the flowers pedicellate; inflorescence not as above; corolla herbaceous[link through]Ovary cells 2 or 4Ovary cells 3 or 5Petals twisted in bud (ie aestivation contorted); flowers radially symmetricalPetals valvate or imbricate in bud, but not regularly twisted; flowers radially or bilaterally symmetricalLeaves alternate; plants terrestrialLeaves opposite or radical, if alternate then plants aquaticCarpels free but with their styles sometimes fused; with copious latexCarpels fully united; without latexHerbsShrubsOvary with 2 cellsOvary with 4 cellsCorolla radially symmetricalCorolla bilaterally symmetricalOvules 1 or 2 in each cellOvules 3 or more in each cellLeaves alternateLeaves oppositeCorolla 5-lobed or, if 4-lobed, then herbsCorolla 4 lobed; plants woody[link through]Style bearing a capitate stigmaStyle bearing a cup-shaped indusiumOvules 3 or more in each cellOvules 1 or 2 in each cellStamens inserted on a disk at the base of the perianthStamens inserted on the corolla-tubeFruit separating into 4 nutlets; plants glabrous or more often with numerous hairsFruit indehiscent, not separating; branched hairs always presentShrubs; stigma singlePerennial herbs or annuals; stigmas 3 or 5Herbaceous vine; stigmas 2Herbaceous or woody; stigmas 1, 3 or 5Leaves entire; plants glabrousLeaves pinnatisect; plants glandular-hairy