GERANIALES Dumortier Main Tree, Synapomorphies

Takhtajan, Sist. Filog. Cvetk. Rast. [Syst. Phylog. Magnolioph.]: 264. 4 Feb 1967

Rosopsida Batsch, Tab. Regni Veg.: 1. 1802 [’Rosaceae’]; Hamamelididae Takht, Sist. Filog. Cvetk. Rast. [Syst. Phylog. Magnolioph.]: 461. 4 Feb 1967, pro parte; Rosidae Takht., Sist. Filog. Cvetk. Rast. [Syst. Phylog. Magnolioph.]: 264. 4 Feb 1967 pro parte; Dilleniidae Takht. ex Reveal et Takht. in Phytologia 74: 171. 25 Mar 1993, pro parte

MALVIDAE W. S. Judd, D. E. Soltis et P. S. Soltis

MYRTANAE Takht.

Takhtajan, Sist. Filog. Cvetk. Rast. [Syst. Phylog. Magnolioph.]: 295. 4 Feb 1967

Myrtopsida Bartl., Ord. Nat. Plant.: 225, 326. Sep 1830 [’Myrtinae’]; Myrtidae J. H. Schaffn., Ohio Naturalist [’Myrtiflorae’] 11: 416. Dec 1911; Geranianae Thorne ex Reveal in Novon 2: 236. 13 Oct 1992

GERANIALES Juss. ex Bercht. et J. Presl

Habit Bisexual (rarely functionally polygamodioecious), evergreen or deciduous trees or shrubs, suffrutices, perennial or annual herbs (rarely trees), often xerophytic stem-succulents or geophytes, often with root- or stem-tubers.

Vegetative anatomy Phellogen ab initio usually superficial (subepidermal, sometimes outer-cortical). Secondary lateral growth normal or absent (rarely anomalous). Vessel elements usually with simple (rarely reticulate) perforation plates; lateral pits usually alternate (rarely scalariform). Imperforate tracheary xylem elements fibre tracheids or libriform fibres with simple or bordered pits, septate or non-septate (also vasicentric tracheids). Wood rays multiseriate, usually heterocellular (occasionally homocellular) or absent. Axial parenchyma usually paratracheal scanty or vasicentric (sometimes apotracheal diffuse), or absent. Sieve tube plastids S type. Nodes usually 3:3, trilacunar with three leaf traces (sometimes 1:1, unilacunar with one trace, rarely 3:5, trilacunar with five traces, or 5–10:5–10, multilacunar with five to ten traces). Medullary parenchyma with starch grains. Calciumoxalate as single prismatic crystals or groups of crystals, raphides, styloids or druses.

Trichomes Hairs usually multicellular (sometimes unicellular), uniseriate, simple or branched (rarely stellate); glandular hairs simple or branched, often containing ethereal oils.

Leaves Alternate (spiral) or opposite (rarely verticillate), simple or compound, entire or lobed, with conduplicate to plicate ptyxis. Stipules intrapetiolar or interpetiolar (rarely pairwise and lateral, or absent); leaf sheath usually absent. Petiole vascular bundle transection annular. Venation pinnate or palmate, usually brochidodromous or craspedodromous (rarely actinodromous). Stomata usually anomocytic (sometimes paracytic). Cuticular wax crystalloids usually absent (sometimes as rodlets or platelets). Leaflets and lobes usually serrate (sometimes glandular serrate), crenate or sinuate (sometimes entire).

Inflorescence Terminal, axillary or leaf-opposite, corymbose, thyrse, cymose umbel-like or few-flowered (rarely raceme or panicle), or flowers solitary axillary. Floral prophylls (bracteoles) sometimes absent.

Flowers Actinomorphic or zygomorphic. Hypanthium present or absent. Usually hypogyny (rarely half epigyny). Sepals (four or) five, with imbricate (often apically valvate, rarely induplicate-valvate) aestivation, free or connate at base. Petals (two to) five (or six; rarely absent), usually with imbricate (sometimes contorted) aestivation, usually clawed, caducous, free. Nectaries (nectariferous glands) five, antesepalous, alternipetalous, alternating with stamens (nectariferous disc rarely lobate, annular, extrastaminal). Disc extrastaminal (sometimes absent).

Androecium Stamens usually five or 5+5 (rarely four or 4+4, 10+5, or 5+5+5), obdiplostemonous. Filaments usually connate at base (sometimes free), free from tepals. Anthers usually dorsifixed (sometimes basifixed), usually versatile, tetrasporangiate, usually introrse (rarely extrorse or latrorse), longicidal (dehiscing by longitudinal slits). Tapetum secretory or amoeboid-periplasmodial. Staminodia usually absent (sometimes five, extrastaminal, or three to eight, rarely ten, extrastaminal and alternating with stamens).

Pollen grains Microsporogenesis usually simultaneous (rarely successive). Pollen grains (2–)3(–15)-colpate, (2–)3(–15)-colporate or inaperturate (rarely polypantoporate), shed as monads, bicellular or tricellular at dispersal. Exine tectate or semitectate, with columellate infratectum, reticulate, reticulate-striate, or striate, gemmate, echinate or with other types of supratectal processes.

Gynoecium Pistil composed of (two to) five (to seven) antepetalous connate carpels. Ovary usually superior (rarely semi-inferior), (bilocular to) quinquelocular, (bilobate to) quinquelobate. Stylodia (four or) five (style sometimes single, simple, or absent). Stigmas (two to) five (sometimes one, capitate or tri- or quinquelobate), punctate to slightly widened, usually papillate (rarely non-papillate), usually Dry (sometimes Wet) type. Pistillodium absent.

Ovules Placentation usually axile (sometimes marginal, rarely apical, basal or intrusively parietal). Ovules usually one or two (rarely up to twelve, only one of which is developing, or up to c. 50) per carpel, usually anatropous to campylotropous by insertion of inner integument (rarely hemianatropous), ascending, pendulous or ascending, usually epitropous, bitegmic (outer integument sometimes mostly epidermal in origin), crassinucellar. Micropyle usually bistomal (sometimes endostomal), often Z-shaped (zig-zag). Nucellar cap usually absent (rarely present). Megagametophyte monosporous, Polygonum type. Endosperm development ab initio nuclear. Endosperm haustoria? Embryogenesis onagrad or asterad.

Fruit Usually a schizocarp with (four or) five single-seeded (rarely follicular) mericarps (rarely a loculicidal, septicidal or septifragal capsule).

Seeds Aril usually absent. Seed coat usually testal-exotegmic (rarely exotestal). Exotesta usually unspecialized (rarely palisade). Endotesta palisade, consisting of malpighian-like cells with calciumoxalate crystals and thickened unlignified cell walls. Exotegmen usually palisade, with sinuous, anticlinal and poorly lignified cell walls. Endotegmen sometimes with slightly lignified cell walls. Perisperm not developed. Endosperm usually absent (sometimes sparse, rarely copious), oily. Embryo straight to curved (rarely spirally twisted), oily, well differentiated, usually with chlorophyll. Cotyledons two. Germination phanerocotylar.

Phytochemistry Flavonols (kaempferol, quercetin, myricetin), flavone-C-glycosides, desoxyflavonoids with B-ring, monoterpenoids (citronellol, geraniol) and their esters (citronellyl, geraniyl [pelargonium-oil]), oleanolic acid derivatives, ellagic and gallic acids, ellagitannins (e.g. geraniins), alkaloids, toxic bufadienolides, and tartaric acid present. Non-hydrolyzable tannins, proanthocyanidins, and cyanogenic compounds not found.

Melianthaceae and Francoaceae share the following potential synapomorphies (Stevens 2001 onwards): leaves spiral, with fairly broad insertion and conduplicate ptyxis; inflorescence terminal, racemose, with sterile bract(s) at apex; absence of floral prophylls (bracteoles); carpels lobate; long style; placentae intrusive; ovules in two rows; micropyle bistomal; endosperm copious; embryo short; and presence of inulin.

Francoales A. de Jussieu in C. F. P. von Martius, Consp. Regn. Veg.: 48. Sep-Oct 1835 [‘Francoaceae’]; Greyiaceae Hutch., Fam. Fl. Pl. 1: 202. 15 Jan 1926, nom. cons.; Greyiales Takht., Divers. Classif. Fl. Pl.: 265. 24 Apr 1997

Habit Usually bisexual, evergreen or deciduous trees or shrubs (Greyia) or rhizomatous perennial herbs (Francoa, Tetilla).

Vegetative anatomy Phellogen ab initio subepidermal to cortical. Young stem in Francoa and Tetilla with pseudosiphonostele. Cortical or medullary vascular bundles sometimes present. Primary medullary rays wide. Secondary lateral growth normal (Greyia), anomalous or absent. Vessel elements with simple perforation plates; lateral pits alternate to scalariform, bordered pits. Imperforate tracheary xylem elements libriform fibres (sometimes tracheids?) with simple or bordered pits, non-septate. Wood rays multiseriate, homocellular or heterocellular. Axial parenchyma usually paratracheal scanty or vasicentric (in Greyia also with few diffusely dispersed cells). Cambium and wood elements usually storied (tall wood rays not storied). Sieve tube plastids S type. Nodes 3:5, trilacunar with five leaf traces (Francoa, Tetilla), or 9:9, novemlacunar with nine traces (Greyia). Calciumoxalate as raphides, druses, styloids or single prismatic crystals; raphides present in xylem in Greyia.

Trichomes Hairs unicellular or multicellular, uniseriate (sometimes multi-armed); glandular hairs densely spaced in Francoa and Tetilla.

Leaves Alternate (spiral), pinnately compound or simple and pinnately lobed, with conduplicate-plicate ptyxis. Stipules usually absent (rarely present in Greyia); leaf sheath present in Francoa and Greyia; widened leaf bases in Greyia fused with stem and forming pseudocortex. Petiole vascular bundle transection usually annular. Venation palmate or pinnate, actinodromous or craspedodromous (Francoa). Stomata anomocytic. Cuticular wax crystalloids as irregularly orientated platelets, or cuticular waxes absent. Mesophyll with calciumoxalate as raphides (often in idioblasts), druses, styloids or solitary prismatic crystals. Leaf margin usually serrate (rarely entire); hydathodes present in leaf teeth in Greyia.

Inflorescence Usually terminal or lateral (rarely axillary), raceme or panicle. Floral prophylls (bracteoles) absent.

Flowers Actinomorphic or zygomorphic, in Greyia resupinate. Hypogyny or half epigyny. Sepals four or five (Francoa, Tetilla) or (four or) five (Greyia), with contorted to imbricate (or induplicate-valvate?; in Greyia imbricate) aestivation, more or less free, or three sepals free and two connate, without spur; sepals in Greyia persistent. Petals (three or) four or five (or six), usually with imbricate-ascending aestivation, clawed or sessile, unequally sized, recurved, caducous (Greyia), free. Nectariferous disc extrastaminal, large, annular, often lobate (in Greyia decemlobate, corona-like, with ten interstaminal ridges adnate to ovary).

Androecium Stamens in Francoa and Tetilla usually eight (sometimes four), in Greyia (eight or) ten, in one whorl, obdiplostemonous (Francoa, Greyia) or diplostemonous (Tetilla). Filaments usually free (in, e.g., Francoa connate at base), free from tepals. Anthers basifixed, often versatile, tetrasporangiate, latrorse to introrse, longicidal (dehiscing by longitudinal slits). Tapetum secretory, with uninucleate or multinucleate (Francoa) cells. Staminodia in Tetilla four, in Francoa eight, alternating with stamens (lobes of nectariferous disc with ten gland-like extrastaminal staminodia alternating with stamens).

Pollen grains Microsporogenesis simultaneous or successive. Pollen grains tricolporate (Greyia, Francoa) with complex endoapertures, shed as monads, usually bicellular (rarely tricellular) at dispersal. Exine semitectate, with columellate? infratectum, reticulate.

Gynoecium Pistil composed of (three or) four (Francoa, Tetilla) or (four or) five (to seven; Greyia) connate carpels. Ovary superior or semi-inferior, usually quadrilocular or quinquelocular, often deeply lobed (in Greyia unilocular, with carpels paracarp connate, or quinquelocular with free carpels except common central part). Style single, simple, short (Greyia) or absent (Francoa, Tetilla). Stigma entire, punctate or somewhat expanded and ridged (in Greyia quinquelobate; in Francoa and Tetilla commissural, usually with two lobes each composed of two carpels), non-papillate (Greyia), Wet type. Pistillodium?

Ovules Placentation axile to apical, with intrusive placentae (in Greyia intrusively parietal, when ovary unilocular). Ovules c. 20 to c. 50 per carpel, anatropous, pendulous, horizontal or ascending, apotropous, bitegmic, crassinucellar. Micropyle bistomal. Outer integument ? layers thick. Inner integument ? cell layers thick. Funicular obturator present in Francoa and Tetilla. Parietal tissue approx. five cell layers thick. Nucellar cap? Hypostase present. Megagametophyte monosporous, Polygonum type, elongated. Suspensor present in Greyia. Endosperm development ab initio nuclear (Francoa). Endosperm haustoria? Embryogenesis in Greyia asterad.

Fruit A septicidal capsule (Francoa, Tetilla); in Greyia a schizocarp with five ventricidal follicular mericarps.

Seeds Aril absent. Seed coat exotestal (Francoa, Tetilla) or testal-tegmic (Greyia). Testa multiplicative. Exotesta palisade; exotestal cells crystalliferous, elongate, with thickened outer walls. Mesotestal and endotestal cells thin-walled, with calciumoxalate as styloids and other crystal types; endotestal cells in Greyia with thickened and lignified radial walls, in Francoa and Tetilla elongate, with thickened anticlinal walls. Tegmen in Greyia fibrous; in Francoa and Tetilla consisting of pigmented cells. Mesotegmic cells elongate. Perisperm not developed. Endosperm copious, oily and sometimes starchy, thick-walled (Greyia). Embryo minute, straight, well differentiated, with chlorophyll. Cotyledons two, narrow. Radicula with anthocyanin (Francoa). Germination phanerocotylar.

Phytochemistry Deoxyflavonoids with B-ring (Greyia), anthocyanins (in roots), oleanolic acid derivatives, and inulin? present. Flavonols, ellagic acid, proanthocyanidins, saponins, cyanogenic compounds, rutinosides, and cyanolipids not found.

Geraniopsida Meisn., Plant. Vasc. Gen.: Tab. Diagn.: 57, Comm.: 41. 21-27 Mai 1837; Erodiaceae Horan., Char. Ess. Fam.: 192. 30 Jun 1847; Hypseocharitaceae Wedd., Chlor. Andina 2: 288. Nov 1861 [’Hypseocharideae’]; Geraniineae Bessey in C. K. Adams, Johnson’s Universal Cyclop. 8: 461. 15 Nov 1895

Distribution Cosmopolitan except polar areas, especially in temperate and subtropical regions, with their largest diversity in South Africa; few species in tropical regions.

Fossils Fossil pollen grains of Geranium and Pelargonium are known from the Miocene of Spain, and of Pelargonium from the Pliocene of southeastern Australia.

Habit Bisexual, usually perennial or annual herbs (sometimes suffrutices or shrubs; in Geranium section Neurophyllodes trees), some species are xerophytic stem succulents and a large number are geophytes, often with root or stem tubers.

Vegetative anatomy Roots usually diarch (sometimes triarch). Phellogen ab initio usually superficial (in Pelargonium section Hoarea within outermost cortical parenchyma; in Monsonia section Sarcocaulon thick waxy bark, ’bushmen candle’, formed from periderm). Endodermis sometimes significant. Secondary lateral growth normal or absent. Vessel elements usually with simple (rarely reticulate) perforation plates; lateral pits usually alternate. Imperforate tracheary xylem elements libriform fibres with simple pits, often septate (also vasicentric tracheids). Wood rays usually heterocellular (often absent). Axial parenchyma usually paratracheal scanty (sometimes apotracheal diffuse). Sieve tube plastids S type. Nodes 3:3, trilacunar with three leaf traces. Medullary parenchyma with starch grains. Groups of calciumoxalate crystals abundant.

Trichomes Hairs multicellular, simple; glandular hairs containing ethereal oils often frequent, especially on leaves.

Leaves Usually alternate (spiral; sometimes opposite, especially lower ones), often in basal rosette, simple, pinnately or palmately compound, entire or lobed, with conduplicate-plicate ptyxis. Stipules intrapetiolar or interpetiolar (rarely modified into spines; absent in Hypseocharis); leaf sheath absent. Petiolules not articulated. Petiole vascular bundle transection annular. Venation palmate or pinnate. Stomata usually anomocytic (sometimes paracytic). Cuticular wax crystalloids usually absent (rarely as rodlets). Leaflets and lobes usually serrate, crenate or sinuate (sometimes entire).

Inflorescence Terminal, axillary or leaf-opposite, umbel-like cymose, two-flowered cymes in compound cymose partial inflorescences (often pseudo-umbellate; in Geranium geranioid inflorescence, according to Schroeder 1987; multiple thyrse, according to Endress 2010), or flowers solitary axillary (in Monsonia section Sarcocaulon).

Flowers Actinomorphic or zygomorphic. Hypanthium present (Pelargonium) or absent. Hypogyny. Sepals (four or) five, with imbricate (often quincuncial; apically valvate) aestivation, persistent in fruit, aristate, free or connate at base (in Pelargonium adaxial sepal often prolonged into tube); sepal layer with small hypodermal druse-containing cells often present. Petals usually five (rarely two, four or absent), usually with imbricate (sometimes contorted?) aestivation, clawed, caducous, free. Nectaries five, antesepalous, alternipetalous, vascularized, alternating with stamens; nectary in Pelargonium usually deeply sunken into hypanthium; nectaries in Monsonia often in axils of sepals or abaxially on staminal bases (nectariferous disc in Hypseocharis lobate, annular, extrastaminal). Disc usually present.

Androecium Stamens usually five or 5+5 (rarely two, four, seven or 4+4; in Monsonia usually 10+5 [outer ten stamens antepetalous and pairwise, inner five stamens antesepalous], in Hypseocharis usually 5+5+5 [rarely five antepetalous]; when 15, then sometimes five fascicles of three connate stamens), obdiplostemonous or antepetalous. Filaments usually connate at base (sometimes free), free from tepals. Anthers dorsifixed, usually versatile, tetrasporangiate, introrse, longicidal (dehiscing by longitudinal slits). Tapetum secretory or amoeboid-periplasmodial. Staminodia usually absent; in Erodium five, extrastaminal; in Pelargonium three to eight; in one species of Monsonia ten, extrastaminal and alternating with stamens.

Pollen grains Microsporogenesis simultaneous. Pollen grains (2–)3(–15)-colpate (Hypseocharis?, Monsonia) or (2–)3(–15)-colporate (Geranium, Erodium, Pelargonium, Hypseocharis?) or inaperturate, shed as monads, bicellular or tricellular at dispersal; sometimes starchy. Exine tectate or semitectate, with columellate infratectum, striate (often with interwoven striate elements), reticulate, reticulate-striate or reticulate and beset with gemmae or other supratectal processes.

Gynoecium Pistil composed of (four or) five connate carpels, usually prolonged into beak in fruit. Ovary superior, (quadrilocular or) quinquelocular, (quadrilobate or) quinquelobate (in Hypseocharis with gynophore). Stylodia (four or) five (in Hypseocharis one, narrow, simple). Stigmas (four or) five (in Hypseocharis one, capitate), papillate, Dry type. Pistillodium absent.

Ovules Placentation axile(-marginal). Ovules usually one or two (rarely up to twelve, only one of which developing; in Hypseocharis c. 20 to more than 50) per carpel, usually anatropous to campylotropous by invagination of inner integument due to cell development (sometimes hemianatropous), ascending or pendulous, usually epitropous, bitegmic, crassinucellar. Micropyle bistomal (Hypseocharis), Z-shaped (zig-zag) or endostomal (rarely exostomal). Outer integument two or three cell layers thick. Inner integument two or three cell layers thick. Hypostase present in Hypseocharis. Parietal tissue approx. four cell layers thick. Nucellar cap usually absent. Megagametophyte monosporous, Polygonum type. Endosperm development usually nuclear (in Hypseocharis later cellular). Endosperm haustoria? Embryogenesis onagrad or asterad.

Fruit Usually a capsule-like schizocarp with (four or) five one-seeded mericarps; one mericarp and one usually hygroscopic stylar segment dehiscing elastically and acropetally from common central rostrum (central column developed from ovary septa), seeds often thrown out (some species of Hypseocharis with five one- or few-seeded mericarps not connate via central column; in other species of Hypseocharis loculicidal capsule).

Seeds Aril absent. Seed coat endotestal-exotegmic. Exotesta unspecialized. Endotesta palisade, consisting of malpighian-like cells with calciumoxalate crystals and heavily thickened unlignified cell walls. Exotegmen palisade, with poorly lignified sinuous anticlinal cell walls. Endotegmen sometimes with slightly lignified cell walls. Perisperm not developed. Endosperm usually absent (sometimes sparse). Embryo straight to curved (in Hypseocharis coiled), oily, well differentiated, with chlorophyll. Cotyledons two, folded. Radicula dorsal. Germination phanerocotylar.

DNA Plastid genome extensively rearranged in Geraniaceae. Examples as follows. Plastid gene rpl16 intron lost. Plastid gene infA lost/defunct (Erodium, Pelargonium). Plastid gene rpl2 intron lost in Monsonia (incl. Section Sarcocaulon). Plastid gene accD and ORF2280 absent in numerous species. Plastid gene clpP absent in at least two species of Geranium and in Monsonia (incl. section Sarcocaulon). Plastid gene rpoA absent in Pelargonium, and rpl20 from Monsonia section Sarcocaulon. Group II intron between mitochondrial gene nad1 b and c exons absent. In Pelargonium x hortorum the plastid inverted repeat has expanded by 76 kb. Ribosomal protein and succinate dehydrogenase genes transferred from mitochondrial genome to nuclear genome (Erodium). Plastid inverted repeat absent in Erodium and Monsonia section Sarcocaulon. Plastid genome in Erodium chamaedryoides with one or two inversions, in Geranium grandiflorum (?) several inversions, in Pelargonium x hortorum approx. six inversions, and in Monsonia section Sarcocaulon several inversions.

Phytochemistry Flavonols (kaempferol, quercetin, myricetin), flavone-C-glycosides, ellagic and gallic acids, hydrolyzable tannins (ellagitannins, e.g. geraniins), alkaloids, petroselinic acid, and vernolic acid (Geranium) present; in many species of Pelargonium also the monoterpenoids citronellol, geraniol and their esters citronellyl och geraniyl (pelargonium-oil), and tartric acid. Proanthocyanidins and cyanogenic compounds not found.

Use Ornamental plants, perfumes, flavours and aromatic additives (Pelargonium).

Systematics Geraniaceae are sister-group to the remaining Geraniales.

Hypseocharis is sister to the remaining Geraniaceae.

Hypseocharis

1/8. Hypseocharis (8; H. bilobata, H. fiebrigii, H. malpasensis, H. moschata, H. pedicularifolia, H. pilgeri, H. pimpinellifolia, H. tridentata; the Andes in Chile and Argentina). – Perennial acaulescent or almost stemless herbs with tuber or thick taproot. Stipules absent. Nectariferous disc lobate, annular, extrastaminal. Stamens usually 5+5+5, with ten stamens in antepetalous pairs (rarely five antepetalous). Gynophore present. Style single, simple, filiform. Stigma capitate. Ovules approx. c. 20 to more than 50 per carpel. Micropyle bistomal, Z-shaped (zig-zag). Hypostase present. Endosperm development later cellular. Fruit in some species with five one- or few-seeded mericarps not connate via central column, in other species a loculicidal (in H. tridentata septicidal-ventricidal) capsule with persistent filaments. Endosperm sparce. Embryo coiled. Cotyledons alternate. n = ? – Hypseocharis is sister to all other Geraniaceae. – Hypseocharis tridentata seems to be sister to the remaining species of Hypseocharis.

Geranieae Sweet, Geraniaceae 1: vii. 1820

5/c 830. Pelargonium (c 250; Africa, Madagascar, Asia, St. Helena [P. cotyledonis], Tristan da Cunha, Australia, New Zealand, with their highest diversity in the Cape Provinces in South Africa), Monsonia (c 40; Africa, Madagascar, southwestern Asia, with their highest diversity in southern Africa), Geranium (c 415; temperate regions on both hemispheres, tropical mountains, the Hawaiian Islands), Erodium (c 125; Europe, the Mediterranean to Central Asia, southern Australia, southern tropical South America), California (1; C. macrophylla; southern Oregon, California, Baja California in northwestern Mexico). – Subcosmopolitan. Usually annual or perennial herbs (often geophytes; sometimes stem succulents; rarely shrubs). Stem often articulated. Phellogen epidermal. Vessel elements usually with simple (rarely scalariform) perforation plates. Wood rays often absent. Nodes 3:3, trilacunar with three leaf-traces. Glandular hairs often frequent. Leaves usually alternate (sometimes opposite), simple, pinnately or palmately compound, entire or lobed, with conduplicate-plicate ptyxis. Stipules paired, often well developed, interpetiolar or cauline. Colleters present. Petiole vascular bundle transection annular; medullary bundles sometimes present. Cuticular wax crystalloids usually absent (rarely as rodlets). Flowers actinomorphic or zygomorphic (especially in Pelargonium). Sepals often with nectariferous spur (sometimes adaxial spur adjacent to pedicel; in Pelargonium nectary in pedicel; nectary in Monsonia antepetalous), aristate. Petals (four or) five (sometimes fimbriate). Stamens usually 5, 10 or 15 (in Pelargonium two to five or seven, antepetalous staminal whorl staminodial). Filaments often connate at base. Pollen grains rarely colpate, often large, tricellular at dispersal. Pistil composed of (two to) five connate carpels. Style usually short, stout, hollow. Stigma lobate. Placentation apical. Ovules usually one or two per carpel. Micropyle usually endostomal (rarely exostomal). Megagametophyte invading and obliterating apical part of megasporangial tissue. Fruit a capsule-like septicidal schizocarp, with upper ovary part prolonged; mericarps twisting upwards, separating from columella. Exotestal cells stellate in outline, indistinctly delimited. Endotegmic cells walls sometimes slightly lignified. Endosperm absent. Embryo curved, usually with chlorophyll. Cotyledons longitudinally plicate or accumbent. Radicula long. n = 4, 7–11, 14, 15 or higher. Sporophytic incompatibility often occurring.

Cladogram (simplified) of Geraniaceae based on DNA sequence data (Fiz & al. 2008).

Vivianiaceae Klotzsch in Linnaea 10: 433. Mai 1836, nom. cons. prop.; Rhynchothecaceae (Endl.) A. Juss. in V. V. D. d’Orbigny, Dict. Univ. Hist. Nat. 11: 131. 9 Sep 1848 [’Rhyncotheceae’]; Ledocarpales Doweld, Tent. Syst. Plant. Vasc.: xxxvii. 23 Dec 2001

Distribution Western South America, with their highest diversity in the Andes.

Habit Bisexual, evergreen or deciduous shrubs or suffrutices (sometimes perennial or annual herbs). In Rhynchotheca and some species of Viviania many short shoots are modified into spines.

Vegetative anatomy Phellogen? Cork cells with tannins. Medulla parenchymatous or sclerenchymatous. Cortex parenchymatous (without sclerenchyma). Vessel elements with simple perforation plates (in Viviania sometimes with rib crossing perforation); lateral pits circular or elliptic. Imperforate tracheary xylem elements fibre tracheids with simple (Balbisia) or bordered (Viviania) pits. Wood rays absent. Axial parenchyma paratracheal or absent. Wood elements often storied; cambium in Viviania storied. Tyloses spherical or absent. Sieve tube plastids S type. Nodes in Viviania 1:1, unilacunar with one leaf trace. Calciumoxalate druses present.

Trichomes Hairs unicellular, simple or branched; glandular hairs uniseriate, simple or branched.

Leaves Usually opposite or almost opposite (rarely verticillate), simple or compound (pinnately compound or trifoliolate), entire or pinnately lobed, with ? ptyxis. Stipules and leaf sheath absent (petiole bases united by transverse line across stem/branch). Petiole vascular bundle transection? Venation pinnate to subpalmate (Viviania), brochidodromous or craspedodromous. Stomata anomocytic. Cuticular wax crystalloids as platelets (in Viviania band-shaped) or absent. Leaf margin serrate or entire.

Inflorescence Terminal, corymb-like (thyrse with monochasial to asymmetrical dichasial paraclades, often reduced to two or three flowers), or flowers solitary; inflorescence in Viviania sometimes entirely or partially modified into branched spine.

Flowers Actinomorphic. Hypogyny. Epicalyx consisting of bracts present or absent. Sepals four or five, with imbricate (apically valvate) aestivation, persistent in fruit, free or connate at base (in Viviania; sepals in Viviania with eight or ten distinct ridges), often aristate. Calyx layer with small hypodermal druse-containing cells present in Viviania. Petals usually four or five (absent in Rhynchotheca), with contorted or imbricate aestivation, free. Nectary absent or nectariferous glands alternipetalous, rarely bilobate (Viviania). Disc extrastaminal, consisting of separate alternipetalous units (absent in Balbisia).

Androecium Stamens usually five long and five short (in Viviania rarely four, five, eight or 5+5+5), usually obdiplostemonous. Filaments often widened at base and connate into ring (in Viviania often with pair of basal appendages, probably nectaries), free from tepals. Anthers basifixed, non-versatile, tetrasporangiate, introrse or extrorse, longicidal (dehiscing by longitudinal slits). Tapetum secretory? Staminodia absent or as (four or) five nectariferous glands.

Pollen grains Microsporogenesis simultaneous? Pollen grains inaperturate (Balbisia, Wendtia) or 21–60-pantoporate (Rhynchotheca, Viviania), shed as monads, bicellular? at dispersal. Exine usually semitectate (in some species of Viviania pertectate), with columellate infratectum, usually reticulate, often finely echinate.

Gynoecium Pistil composed of two, three or five connate antesepalous carpels; odd carpel in Viviania abaxial. Ovary superior, bilocular, trilocular or quinquelocular and bilobate, trilobate or quinquelobate. Style single, short, or absent. Stigma single, trilobate or quinquelobate, with revolute margins, or two or three; stigmatic areas adaxial, usually Dry type (in Rhynchotheca Wet type and mucilaginous). Pistillodium absent.

Ovules Placentation usually axile (rarely apical). Ovules usually one or two to twenty, collateral or superposed (rarely more than twenty; in Viviania two, superposed) per carpel, anatropous (Rhynchotheca), twisted and campylotropous (Viviania) or hemianatropous to campylotropous (Balbisia), ascending or pendulous, epitropous, bitegmic, crassinucellar. Micropyle endostomal. Outer integument two or three cell layers thick. Inner integument two or three cell layers thick. Integument more or less thickened near micropyle. Obturator hairy at funicle. Nucellar cap present. Megagametophyte monosporous, Polygonum type. Endosperm development ab initio nuclear. Endosperm haustoria? Embryogenesis?

Fruit Usually a loculicidal and sometimes septifragal (Balbisia, Rhynchotheca) or septicidal (Rhynchotheca, Viviania) acute capsule (in Rhynchotheca with columella).

Seeds Aril absent. Funicle hairy. Testa four- or five-layered (in Viviania sometimes hairy). Raphe in Viviania tanniniferous. Exotesta inBalbisia often with mucilaginous or tanniniferous cells (some representatives of Rhynchotheca and Viviania with thick-walled, narrowly elongate, non-lignified exotegmic cells). Endotesta? Exotegmic cells in Viviania sometimes thick-walled, elongate, unlignified. Endotegmen tanniniferous. Perisperm not developed. Endosperm sparse (in Rhynchotheca thin-walled) or copious and starchy (some species of Viviania), oily, with thick and pitted cell walls. Embryo straight (Rhynchotheca), cordate or spirally twisted (Viviania, in some species with long suspensor), or strongly twisted (Balbisia), well differentiated, sometimes with chlorophyll (Viviania). Cotyledons one? (Viviania, Rhynchotheca) or two (Balbisia). Germination?

Phytochemistry Very insufficiently known. Anthocyanins and ellagitannins present.

Melianthales Bercht. et J. Presl, Přir. Rostlin: 220. Jan-Apr 1820 [‘Meliantheae’]; Bersamaceae Doweld in Plant Syst. Evol. 227: 83. 7 Mai 2001

Habit Usually bisexual (in Bersama functionally polygamodioecious), evergreen or deciduous small trees or shrubs (Bersama) or suffrutices (Melianthus).

Vegetative anatomy Phellogen ab initio subepidermal to cortical. Cortical or (phloic) medullary vascular bundles sometimes present. Primary medullary rays wide. Secondary lateral growth anomalous or absent. Vessel elements with simple perforation plates; lateral pits alternate to scalariform, bordered pits. Imperforate tracheary xylem elements libriform fibres (sometimes tracheids?) with simple or bordered pits, non-septate. Wood rays multiseriate, homocellular or heterocellular. Axial parenchyma usually paratracheal scanty or vasicentric. Cambium and wood elements usually storied (tall wood rays not storied). Sieve tube plastids S type. Nodes 5–10:5–10, multilacunar with five to ten leaf traces. Calciumoxalate as raphides, druses, styloids or single prismatic crystals.

Trichomes Hairs unicellular or multicellular, uniseriate or multiseriate, simple or branched (sometimes multi-armed, sometimes stellate); glandular hairs often present.

Leaves Alternate (spiral), imparipinnate (leaflets entire, articulated), with conduplicate-plicate ptyxis. Stipules paired and usually lateral, cauline, persistent (Melianthus), or single intrapetiolar and caducous (Bersama); leaf sheath absent. Petiole vascular bundle transection usually annular; petiole sometimes with cortical or medullary vascular bundles. Venation palmate or pinnate, actinodromous. Stomata anomocytic. Cuticular wax crystalloids as irregularly orientated platelets, or cuticular waxes absent. Mesophyll with calciumoxalate as raphides (often in idioblasts), druses or styloids (sometimes solitary prismatic crystals). Leaf margin usually serrate (rarely entire); hydathodes present in leaf teeth in at least Bersama.

Inflorescence Usually terminal (rarely axillary), raceme or panicle. Floral prophylls (bracteoles) absent.

Flowers Zygomorphic (in Bersama with zygomorphic calyx), resupinate (in Melianthus with significant mentum consisting of adaxially widened receptacle). Hypogyny or half epigyny. Sepals (four or) five (in Melianthus two showy adaxial sepals arched at least above androecium and gynoecium), with induplicate to valvate aestivation, more or less free, or three sepals free and two connate, adaxial sepal with (Melianthus) or without spur. Petals (three or) four or five (or six), with imbricate-ascending (contorted?) or valvate (Bersama) aestivation, clawed or sessile, unequally sized, recurved, free (in Melianthus densely connivent via crystalline hairs). Nectary adaxial, extrastaminal, large, annular (nectariferous disc; Bersama) or unilateral, often lobed.

Androecium Stamens four, haplostemonous, antesepalous, alternipetalous, without adaxial stamens. Filaments free from each other and from tepals. Anthers usually basifixed (in Bersama dorsifixed), often versatile, tetrasporangiate, latrorse to introrse, longicidal (dehiscing by longitudinal slits). Tapetum secretory, with uninucleate or multinucleate cells. Staminodia?

Pollen grains Microsporogenesis simultaneous or successive. Pollen grains dicolporate or tricolporate (Melianthus), shed as monads, usually bicellular (rarely tricellular) at dispersal. Exine semitectate, with columellate? infratectum, reticulate.

Gynoecium Pistil composed of (three or) four (Melianthus), or (four or) five (to seven; Bersama) connate carpels. Ovary superior or semi-inferior, usually quadrilocular or quinquelocular, lobate. Style single, simple. Stigma entire, punctate or somewhat widened and ridged, non-papillate?, Wet type. Male flowers in Bersama with pistillodium.

Ovules Placentation usually axile to apical (in Bersama basal), with intrusive placentae. Ovule one (Bersama) or two to five (Melianthus), anatropous, pendulous, horizontal (Melianthus) or ascending (Bersama), apotropous, bitegmic, crassinucellar. Micropyle endostomal (Melianthus) or bistomal (Bersama). Outer integument three to seven cell layers thick. Inner integument two to four cell layers thick. Funicular obturator? Hypostase present, later massive. Nucellar cap present in Melianthus. Megagametophyte monosporous, Polygonum type. Endosperm development ab initio nuclear. Endosperm haustoria? Embryogenesis asterad.

Fruit A membranous caducous (some species of Melianthus) or coriaceous to woody persistent capsule, loculicidal (in Bersama also partially septicidal).

Seeds Aril usually absent (present in Bersama). Seed coat exotestal. Testa multiplicative (to 20 or more cell layers). Exotesta palisade, crystalliferous, with thick outer cell walls. Mesotestal and endotestal cells thin-walled, with calciumoxalate as styloids and other crystal types. Tegmen crushed, unlignified. Mesotegmic cells elongating. Perisperm not developed. Endosperm copious, oily and sometimes starchy, thick-walled (Bersama) or with amyloid (xyloglucans; Melianthus). Embryo small, straight, well differentiated, with chlorophyll. Cotyledons two, narrow. Germination phanerocotylar.

Phytochemistry Flavonols (quercetin, myricetin), anthocyanins (in roots), oleanolic acid derivatives, ellagic acid, toxic bufadienolides (cardiac glycosides), glucuronide triterpenoid saponins, and inulin present. Proanthocyanidins, saponins, cyanogenic compounds, rutinosides, and cyanolipids not found.

Use Ornamental plants, medicinal plants, timber, carpentries, aromatic substances (incense wood).

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ROSANAE Takht.

MALVIDAE W. S. Judd, D. E. Soltis et P. S. Soltis

MYRTANAE Takht.

GERANIALES Juss. ex Bercht. et J. Presl

FRANCOACEAE A. Juss.

GERANIACEAE Juss.

LEDOCARPACEAE E. Mey.

MELIANTHACEAE Horan.