LIGNOPHYTA

True roots +; lateral meristems: cork cambium producing cork abaxially, vascular cambium producing phloem abaxially and xylem adaxially.

EXTANT SEED PLANTS/SPERMATOPHYTA

Plant woody, evergreen; nicotinic acid metabolised to trigonelline, (cyanogenesis via tyrosine pathway); primary cell walls rich in xyloglucans and/or glucomannans, 25-30% pectin [Type I walls]; lignins derived from (some) sinapyl and particularly coniferyl alcohols, thus containing p-hydroxyphenyl and guaiacyl lignin units, (lignins derived from p-coumaryl alcohol, i.e. S [syringyl] lignin units); true roots present, apex multicellular, xylem exarch, and branching endogenous; arbuscular mycorrhizae +; shoot apical meristem multicellular, interface specific plasmodesmatal network; stem with ectophloic eustele, endodermis 0, xylem endarch, branching exogenous; vascular tissue in t.s. discontinuous by interfascicular regions; vascular cambium + [xylem ("wood") differentiating internally, phloem externally]; wood homoxylous, tracheids and rays alone, tracheid/tracheid pits circular, bordered; mature sieve tube/cell lacking functioning nucleus, plastids with starch grains; phloem fibres +; stem cork cambium superficial, root cork cambium deep seated; leaves with single trace from sympodium ["nodes 1:1"]; stomata ?; leaf vascular bundles collateral; leaves megaphyllous [determinancy evolved first, then ad/abaxial symmetry], spiral, simple, lamina with vein density up to 5 mm/mm² [mean for all non-angiosperms 1.8]; axillary buds associated with at most some leaves; prophylls [including bracteoles] two, lateral; plant heterosporous, sporangia eusporangiate, on sporophylls, sporophylls aggregated in indeterminate cones/strobili; true pollen [microspores, i.e. no distal pore for release of gametes] +, grains mono[ana]sulcate, exine and intine homogeneous; ovules unitegmic, crassinucellate, megaspore tetrad tetrahedral, only one megaspore develops, megasporangium indehiscent; male gametophyte development first endo- then exosporic, tube developing from distal end of grain, to ca 2 mm from receptive surface to egg, gametes two, developing after pollination, with cell walls, with many flagellae; female gametophyte endosporic, initially syncytial, walls then surrounding individual nuclei; seeds "large", first cell wall of zygote transverse, embryo straight, endoscopic [suspensor +], short-minute, with morphological dormancy, white, cotyledons 2; plastid transmission maternal; two copies of LEAFY gene, PHY gene duplications [three - [BP [A/N + C/O]] - copies], nrDNA with 5.8S and 5S rDNA in separate clusters; mitochondrial nad1 intron 2 and coxIIi3 intron and trans-spliced introns present.

MAGNOLIOPHYTA

Lignans, O-methyl flavonols, dihydroflavonols, triterpenoid oleanane, non-hydrolysable tannins, quercetin and/or kaempferol +, apigenin and/or luteolin scattered, [cyanogenesis in ANITA grade?], S [syringyl] lignin units common, positive Maüle reaction [syringyl:guaiacyl ratio more than 2-2.5:1], and hemicelluloses as xyloglucans; root apical meristem intermediate-open; root vascular tissue oligarch [di- to pentarch], lateral roots arise opposite or immediately to the side of [when diarch] xylem poles; origin of epidermis with no clear pattern [probably from inner layer of root cap], trichoblasts [differentiated root hair-forming cells] 0; shoot apex with tunica-corpus construction, tunica 2-layered; reaction wood ?, with gelatinous fibres; starch grains simple; primary cell wall mostly with pectic polysaccharides, poor in mannans; tracheid:tracheid [end wall] plates with scalariform pitting, wood parenchyma +; sieve tubes enucleate, sieve plate with pores (0.1-)0.5-10< µm across, cytoplasm with P-proteins, cytoplasm not occluding pores of sieve plate, companion cells from same mother cell that gave rise to the sieve tube; sugar transport in phloem passive; nodes unilacunar [1:?]; stomata with ends of guard cells level with pore, paracytic, outer stomatal ledges producing vestibule; leaves petiolate, lamina [formed from the primordial leaf apex], development of venation acropetal, 2ndary veins pinnate, fine venation reticulate, veins (1.7-)4.1(-5.7) mm/mm², endings free; most/all leaves with axillary buds; flowers perfect, pedicellate, polysymmetric, parts spiral [esp. the A], free, numbers unstable, development in general centripetal; P not sharply differentiated, with a single trace, outer members not enclosing the rest of the bud, often smaller than inner members; A many, filament not sharply distinguished from anther, stout, broad, with a single trace, anther introrse, tetrasporangiate, sporangia in two groups of two [dithecal], ± embedded in the filament, with at least outer secondary parietal cells dividing, each theca dehiscing longitudinally by action of hypodermal endothecium, endothecial cells elongated at right angles to long axis of anther; tapetum glandular, binucleate; microspore mother cells in a block, microsporogenesis successive, walls developing by centripetal furrowing; pollen subspherical, tectum continuous or microperforate, ektexine columellar, endexine thin, compact, lamellate only in the apertural regions; nectary 0; G free, several, ascidiate, with postgenital occlusion by secretion, stylulus short, hollow, cavity not lined by distinct epidermal layer, stigma ± decurrent, dry [not secretory]; ovules few [?1]/carpel, marginal, anatropous, bitegmic, micropyle endostomal, outer integument 2-3 cells across, often largely subdermal in origin, inner integument 2-3 cells across, often dermal in origin, parietal tissue 1-3 cells across [crassinucellate], nucellar cap?; megasporocyte single, hypodermal, megaspore tetrad linear, functional megaspore chalazal, lacking sporopollenin and cuticle; female gametophyte four-celled [one module, nucleus of egg cell sister to one of the polar nuclei]; P deciduous in fruit; seed exotestal; pollen binucleate at dispersal, trinucleate eventually, germinating in less than 3 hours, pollination siphonogamous, tube elongated, growing at 80-600 µm/hour, with pectic outer wall, callose inner wall and callose plugs, growing between cells, penetration of ovules via micropyle [porogamous] within ca 18 hours, distance to first ovule 1.1.-2.1 mm, tube moves between nucellar cells; double fertilisation +, endosperm diploid, cellular [micropylar and chalazal domains develop diffently, first division oblique, micropylar end initially with a single large cell, divisions uniseriate, chalazal cell smaller, divisions in several planes], copious, oily and/or proteinaceous, embryo cellular ab initio, minute; germination hypogeal, seedlings/young plants sympodial; Arabidopsis-type telomeres [(TTTAGGG)_n]; whole genome duplication, ndhB gene 21 codons enlarged at the 5' end, single copy of LEAFY and RPB2 gene, knox genes extensively duplicated [A1-A4], AP1/FUL gene, paleo AP3 and PI genes [paralogous B-class genes] +, with "DEAER" motif, SEP3/LOFSEP and three copies of the PHY gene, [PHYB [PHYA + PHYC]].

Evolution. Possible apomorphies for flowering plants are in bold. Note that the actual level to which many of these features, particularly the more cryptic ones, should be assigned is unclear. This is because some taxa basal to the [magnoliid + monocot + eudicot] group have been surprisingly little studied, there is considerable homoplasy as well as variation within and between families of the ANITA grade in particular for several of these characters, and also because details of relationships among gymnosperms will affect the level at which some of these characters are pegged. For example, if reticulate-perforate pollen is optimized to the next node on the tree (see Friis et al. 2009 for a discussion), it effectively makes the pollen morphology of the common ancestor of all angiosperms ambiguous... For other features such as details of sugar transport in the phloem, their placement on the tree is frankly speculative. Finally, for features such as parietal tissue/a nucellus only one (Nymphaeales) to three cells thick above the embryo sac and a stylar canal lacking an epidermal layer, although plesiomorphous for basal grade angiosperms (Williams 2009), I am unsure where on the tree a thicker nucellus and a stylar epidermal layer are acquired.

[NYMPHAEALES [AUSTROBAILEYALES [[CHLORANTHALES + MAGNOLIIDS] [MONOCOTS [CERATOPHYLLALES + EUDICOTS]]]]]: vessels +, elements with elongated scalariform perforation plates; wood fibres +; axial parenchyma diffuse or diffuse-in-aggregates; tectum reticulate-perforate [here?]; ?genome duplication; "DEAER" motif in AP3 and PI genes lost, gaps in these genes.

[ERICALES [ASTERID I + II]]: ovules tenuinucellate.

[ASTERID I + II] / CORE ASTERIDS: ellagic acid 0, non-hydrolysable tannins not common; sugar transport in phloem active; inflorescence basically cymose; C forming a distinct tube; A epipetalous, = and opposite sepals or P, polyandry associated with increased numbers of C or G, very uncommon; (pollen with orbicules); duplication of the PI gene.

ASTERID I / LAMIIDAE: G [2], superposed; loss of introns 18-23 in d copy of RPB2 gene.

[BORAGINACEAE + VAHLIACEAE + GENTIANALES + LAMIALES + SOLANALES]: (8-ring deoxyflavonols +); vessel elements with simple perforation plates; C tube initiation late [sampling!]; [vascularized] nectary at base of G; style long.

[LAMIALES + SOLANALES]: iridoids, myricetin, non-hydrolysable tannins usu. 0; nodes 1:1; K connate; anther sacs with placentoids.

SOLANALES Berchtold & J. Presl  Main Tree, Synapomorphies.

O-methyl flavonols (flavones) +; inflorescence terminal; pollen tube usu. with callose; K persistent in fruit; endosperm development? - 5 families, 165 genera, 4080 species.

Evolution. Divergence & Distribution. Stem group Solanales may date from the Campanian-Santonian 86-82 million years before present, diversifying 78-76 million years before present (Wikström et al. 2001: Sphenoclea not included); Janssens et al. (2009) date stem group Solanales to 101±11.8 million years ago; Bremer et al. (2004) date the stem clade to ca 106 million years ago and the crown clade to ca 100 million years; Magallón and Castillo (2009) suggest ages of ca 77 and 73 million years for both relaxed and constrained penalized likelihood datings for stem and crown group Solanales respectively - but note topology.

Phylogeny. Montiniaceae are placed next to Solanaceae + Convolvulaceae (B. Bremer 1996, see also Soltis & Soltis 1997; cf. Takhtajan 1997 - in Hydrangeales). D. Soltis et al. (2000) found strong support for the association of Montinia and Hydrolea; Sphenoclea was not included. With the inclusion of the latter and broader sampling (three genera) in Montiniaceae, B. Bremer et al. (2002) found strong support for the association of Sphenoclea and Hydrolea, but only just above 50% for the association of Montiniaceae with that pair; support was stronger in Soltis et al. (2011). The topology of the backbone of the tree here follows that of the latter paper.

Includes Convolvulaceae, Hydroleaceae, Montiniaceae, Solanaceae, Sphenocleaceae.

Synonymy: Cestrales Martius, Convolvulales Berchtold & J. Presl, Cuscutales Martius, Hydroleales Martius, Nolanales Lindley, Sphenocleales Doweld

Montiniaceae [Sphenocleaceae + Hydroleaceae]: alkaloids +; petiole bundle(s) arcuate.

Evolution. "Pits vestured" may be best placed at this node.

MONTINIACEAE Nakai   Back to Solanales

Shrubs, trees (lianes); plants with a peppery smell; route II secoiridoids +, plant slightly tanniniferous; cambium storied or not; pits vestured; young stem with a vascular cylinder (separate bundles; medullary bundles +); pericyclic fibres 0; nodes 1:1 (?-11:11 - Kaliphora); crystal sand, acicular crystals and styloids usu. all +; petiole arc of (rounded) bundles (+ additional strands); axillary tuft of hairs at nodes; (stomata anisocytic - some Grevea); leaves also opposite; bracteoles 0; flowers imperfect, small; K small, C free [absolutely so - Montinia], valvate or not; nectary vascularized; staminate flowers: 3-4(-5)-merous; anthers extrorse, ± basifixed; pollen grains large; pistillode minute; carpellate flowers: 4-merous; A staminodial (0); ovary inferior, placentation intrusive parietal-subaxile, style short, stout, hollow, stigma with 2 large lobes; ovules 1-12/carpel, (campylotropous, apotropous - Kaliphora), parietal tissue ?ca 1 cell across, nucellus base thin [Montinia], endothelium?; fruit a capsule; seeds winged, exotesta lignified, periclinal walls thickened, (adjacent wall of mesotesta also thickened - Montinia); fruit indehiscent, placentae at least initially fleshy; testa thin-walled, ± pulpy when wetted [Grevea]; fruit a drupe; (exotesta not persistent Grevea); endosperm +/0, ?development, hemicellulosic, walls thick, layered, cotyledons accumbentfoliaceous, radicle oblique; cotyledonary petioles connate [Montinia]; n = 16 [Kaliphora], 34 [Montinia].

3[list]/5. Africa and Madagascar (map: from Milne-Redhead & Metcalfe 1955; Verdcourt 1975; Bosser 1990; Brummit 2007 [C. and W. Africa]). [Photos - Kaliphora, Montinia Fruits © Serban Procheŝ.]

• Montiniaceae are woody plants that can be recognised by the persistent short style with large stigmatic lobes that cap the smooth fruit; the ovary is inferior. The often 4-merous flowers are small, with free, valvate petals and extrorse, more or less basifixed anthers. Crushed tissue may have a spicy or acrid smell.

Chemistry, Morphology, etc. Pericyclic fibres may be poorly developed - see Kaliphora, ?others; Grevea has vascular bundles in the pith. The axillary tufts of hairs are at best poorly developed in Kaliphora and are probably not apomorphic for the family. The pollen (Hideux & Ferguson 1976) is rather like that of some Araliaceae.

See Milne-Redhead and Metcalfe (1955) for general morphology and anatomy, Mauritzon (1933) for a little embryology, Hegnauer (1973, 1990, as Saxifragaceae) for chemistry, Dahlgren et al. (1977) for germination and iridoids, Ramamonjiarisoa (1980), Carlquist (1989), and Wangerin (1906), Gregory (1998) for vegetative anatomy, Krach (1976, 1977) and Takhtajan and Trifonova (1999) for testa anatomy, and Ronse Decraene (1992) and Ronse Decraene et al. (2000a) for floral details.

Previous Relationships. Montiniaceae have been hard to place, and have generally been included somewhere around Saxifragaceae. Cronquist (1981) included them in his heterogeneous Grossulariaceae, while Takhtajan (1997) placed them as a separate family (Kaliphoraceae were adjacent) in his Hydrangeales.

Synonymy: Kaliphoraceae Takhtajan

Sphenocleaceae + Hydroleaceae: placentae swollen [?level]; ovules many/carpel; endosperm cellular, at most scanty, with multicellular micropylar and chalazal haustoria.

SPHENOCLEACEAE Baskerville   Back to Solanales

Herbs, rather fleshy, annual; fructose with isokestose linkages, cyclic thiosulphinates [zeylanoxides] +; cork ?mid-cortical; cortical air spaces +; stomata tetracytic; inflorescences spicate; C tube formation early, C quincuncial, free, lateral veins connate and commissural; pollen trinucleate; nectary 0; G ± inferior, placenta massive, style short, stigma subcapitate, wet; integument "massive", hypostase 0; synergids elongated, antipodal cells degenerate; fruit capsular, capsule circumscissile; exotestal cells polygonal, with inner walls thickened and with radial spine-like processes; endosperm slight, walls thick; n = 12, 16, 20, etc.

1/2. Pantropical. [Photo - Habit © B. Hammel]

• Sphenocleaceae are erect fleshy annuals of damp or flooded habitats with entire, spirally-arranged leaves and dense terminal spikes of small flowers with more or less inferior ovaries. The small fruits are circumscissile, the lid coming off just below the point of origin of the calyx. Older stems have a green reticulation marking the plates of cells in the cortical tissue that bounds the air spaces.

Chemistry, Morphology, etc. Corolla tube formation is of the early type, and the corolla lobes are characteristically incurved; the lateral veins of adjacent lobes are fused producing commissural veins. The anticlinal walls of the testa are shown as being massively thickened in Takhtajan (2010).

Some information is taken from Kausik and Subramanyam (1946: embryology), Subramanyam (1950b: general), Monod (1980), Erbar (1995c: floral morphology), and Tobe and Morin (1996: embryology).

Previous Relationships. Sphenocleaceae, along with Hydrolea, another genus of uncertain position, were placed near Boraginaceae by Cosner et al. (1994). However, in morphological studies (e.g. Gustafsson & Bremer 1995) Sphenocleaceae seem to be satisfactorily positioned well within Asterales. Indeed, Sphenocleaceae have often been associated with Campanulaceae (e.g. they are placed in Campanulales by Takhtajan 1997), although they lack latex.

HYDROLEACEAE Edwards   Back to Solanales

Herb to shrubby; chemistry?; axillary-sublateral thorns or not; cork?; vessel elements?; pits vestured; stomata?; lamina margin toothed to entire; flowers 4-5-merous, K basally connate, C tube formation late, connate; A versatile; nectary 0/+; G diagonal, [2(-4)], placentae bilobed, styles separate, ± spreading, stigma slightly funneliform or capitate; ovules mostly pleurotropous, funicular bundle absent, integument 6-8 cells across; antipodals degenerating early; fruit a septi-(+ loculi)cidal capsule, (irregularly dehiscent); seeds longitudinally ridged and ruminate, exotestal cells thin-walled, endotestal cells tanniniferous, with a cuticle; n = (9) 10 (12).

1/12. Tropical, warm temperate (map: from Davenport 1988; FloraBase 2007). [Photo - Hydrolea Flower © B. Kenney]

• Hydroleaceae are more or less shrubby plants growing near or even in water. They have rather small leaves, flowers with a blue, broadly campanulate corolla, and an ovary with separate, more or less spreading styles.

Chemistry, Morphology, etc. Hydrolea appears to lack mycorrhizae. The axillary inflorescences may be cymose. Davenport (1988) suggested that the disc is absent. The two carpels are shown as being oblique by Schnizlein (1843-1870: fam. 147), and this is confirmed by Erbar et al. (2005), even for Hydrolea palustris, which has flowers with the median sepal abaxial. Di Fulvio (1997) notes that the four ventral bundles of the two carpels are all connate in the center of the ovary - cf. Hydrophyllaceae s. str., where there are two or four such bundles (di Fulvio 1999). There are no nuclear inclusions (di Fulvio 1991).

Details of embryology are taken from Svensson (1925) and di Fulvio (1989b, 1990); Davenport (1988) monographed the genus.

Previous Relationships. Hydrolea has usually been included in Hydrophyllaceae (e.g. Cronquist 1981; Takhtajan 1997). Not only molecular differences but also axile versus parietal placentation and embryological differences (see di Fulvio de Basso 1990) separate the two.

Convolvulaceae + Solanaceae: coumarins, caffeic acid esters, tropane [polyhydroxynortropanes], pyrrolidine, etc., alkaloids, flavonol and flavone glycosides, acylated anthocyanins +, tannins 0; internal phloem +; leaves with conduplicate vernation; flowers with oblique symmetry; C-tube formation late, C contorted-plicate or induplicate-valvate; G opposite petals; ovules many/carpel, integument (5-)9-20(-40) cells across, (endothelium ?0); K persistent in fruit; testa often multiplicative; young seeds starchy, cotyledons incumbent.

Evolution. Divergence & Distribution. This clade may have diverged 78-76 million years before present, diversifying perhaps 66-65 million years before present (Wikström et al. 2001).

It is possible that flowers with oblique symmetry may be an apomorphy at this level.

Plant-Animal Interactions. Chrysomelidae-Cassidinae+Hispinae and -Criocerinae beetle larve like members of this clade, especially Convolvulaceae (Schmitt 1988; Jolivet 1988; Buzzi 1994; Vencl & Morton 1999).

Chemistry, Morphology, etc. Pyrrolizidine, tropane and pyrrolidine alkaloids are all synthesised from an ornithine precursor (Hegnauer 1973; Dahlgren 1988). Gemeinholzer and Wink (2001) discuss the sporadic distribution of tropane alkaloids in Solanaceae; they are known from Schizanthus and other clades; see Schimming et al. (1998) for the distribution of polyhydroxynortropanes (in most Convolvulaceae, not in Cuscuteae, unknown in Humbertia, scattered in Solanaceae. Eich (2008) provides an extensive summary of the distribution of secondary metabolites in these two families.

The contorted-plicate or induplicate-valvate aestivation of the corolla that is common in this clade results in the open corollas having lobes with a central area that is distinct from the rest; cf. the "winged" corolla scattered in Asterales. Corner (1976) did not mention any endothelium in Convolvulaceae, but cf. Kaur (1969) and Kaur and Singh (1970).

CONVOLVULACEAE Jussieu, nom. cons.   Back to Solanales

Plant laticiferous; stomata usu. paracytic; lamina margins entire; K quincuncial, large, free; anther placentoid 0; pollen tectum imperforate; stigma dry; ovules apotropous.

57[List]/1625 - two groups below. World wide (map: from Meusel et al. 1978; Staples & Brummit 2007).

1. Humbertioideae Roberty

Large tree; chemistry?; vascular bundles collateral; petiole bundle annular; usu. articulated latex canals, or latex cells in the flowers alone; flowers single, axillary, strongly obliquely monosymmetric; A adnate to base of C, filaments bent in bud; ?pollen; style clavate; ?ovule morphology; fruit a few-seeded drupe; ?seed coat; endosperm copious; n = ?

1/1: Humbertia madagascariensis. Madagascar.

Synonymy: Humbertiaceae Pichon, nom. cons.

2. Convolvuloideae Burnett

Plants herbaecous, right-twining vines (lianes to 30 m; trees); (ergoline alkaloids + - from clavicipitalean fungi); (cork pericyclic); secondary thickening anomalous; (fibers or sclereids +); unicellular T-shaped hairs common (hairs stellate); leaves conduplicate, (compound; margins lobed; toothed [dentate - Hyalocystis]), 2ndary veins pinnate to palmate; inflorescence usu. a dichasium; tapetum cells multinucleate; pollen pantoporate or 3-polycolpate, (surface reticulate - some Cuscuta); G [2(-5)], (false septum - Mina), style single or styles separate, stigmas capitate, with multicellular papillae or punctate and smooth; ovules (1-)2(-4)/carpel, erect, integument vascularized, with unbranched bundle, parietal tissue 1-2 cells across, placental obturator common; embryo sac much elongated [Ipomoea]; fruit usu. a variously dehiscent capsule; testa anatomy complex, exotesta with papillae or hairs, usu. little thickened, outer hypodermis of small cells, little thickened, inner hypodermis elongated or not, of 1+ palisade layers, thickened, 2-8 layers of sclereidal cells underneath, (cells little elongated and thickened - Erycibeae, Maripeae); endosperm nuclear, storing galactomannans [?always], embryo green, curved, cotyledons often complexly folded or coiled, bifid, suspensor haustorium +; n = 7-15+; chloroplast gene atpB with 6-15 bp deletion, ycf15 absent, trnF with 150 bp deletion, rpl2 intron 0; sporophytic incompatibility system present.

56/1600: Ipomoea (500 - I. batatas, the sweet potato), Cuscuta (145), Convolvulus (100), Argyreia (90), Jacquemontia (90), Erycibe (75), Merremia (70). World-wide. [Photo - Flower, Fruit.]

Synonymy: Cressaceae Rafinesque, Cuscutaceae Dumortier, nom. cons., Dichondraceae Dumortier, nom. cons., Erycibaceae Meisner, Evolvulaceae Berchtold & J. Presl, Poranaceae J. Agardh

• Convolvulaceae are recognisable by their usually viny habit and leaves with palmate venation; the plants are often obviously laticiferous. The quincuncial calyx is often notably persistent; the sepals are free, and are rarely green in fruit, often being brown and woody - as in wood roses (Merremia tuberosa) - to scarious. The large, radially symmetric corolla has contorti-plicate or induplicate-valvate aestivation and the five stamens are adnate to the tube. The gynoecium is bicarpellate, each loculus usually having two ovules (you rarely need to check this since the calyx is so distinctive), and the seeds have a notably hard, often shiny testa.

Evolution. Ecology. The Convolvuloideae clade has about the second highest number of scandent species in the New World (Apocynaceae are number 1, Fabaceae are ± = number 2 - Gentry 1991).

Cuscuta is a morphologically quite distinctive (see below) parasite, although at least some retain some chlorophyll. Interestingly, Cuscuta exaltata, at least, has retained most of the genes associated with photosynthesis, perhaps because of their involvement in lipid synthesis (McNeal et al. 2007). For a model of nutrient flow between host and parasite, see Hibberd and Jaeschke (2001).

Floral Biology & Seed Dispersal. The flowers often last for only a single day. Smith et al. (2010) noted that white corollas were relatively uncommon in Ipomoea subg. Quamoclit because clades in which they evolved speciated relatively less than the others, while McDonald et al. (2011) discuss the numerous origins of self- from cross pollination (and reversals) in Ipomoea.

Convolvulaceae are described as being the only asterid family that has seeds showing physical dormancy. This is caused by the thick, hard seed coat found in most members of the family, water initially penetrating the seed only at particular places in the coat (Jayasuriya et al. 2009); indeed, such thick and complex seed coats are decidedly uncommon in the asterids.

Bacterial/Fungal Associations. The ergoline alkaloids of a number of Convolvulaceae (Ipomoea, Turbina) appear to be synthesized by clavicipitalean fungi, being found in tissues where those fungi also occur (e. g. Ahimsa-Müller et al. 2007; Markert et al. 2008).

Chemistry, Morphology, etc. Glycine betaines are rather commonly accumulated in Convolvulaceae (Rhodes & Hanson 1993), perhaps surprising since it is not a family of halophytes. Wood fluorescence occurs, but not often. Humbertia has hard wood with the odor of sandalwood. Successive cambia have been reported from some species of Ipomoea (Terrazas et al. 2011).

The bracts may be adnate to the pedicel and accrescent (wind dispersal: Neuropeltis), or the bracteoles may be much enlarged (e.g. Calystegia). Some Convolvuloideae have flowers with slight oblique disymmetry (Lefort 1951), while the zygomorphy of the flowers of Humbertia is largely positional, indeed, they are drawn as being polysymmetrical by Pichon (1947). The sepals of Humbertia have five traces, but in Convolvuloideae there are fewer; secretory cells are apparently restricted to the flower (Deroin 1993). The corolla tube of some Cuscuta and some other members of the family is strictly speaking a corolla-stamen tube, both contributing integrally to the tubular structure (Prenner et al. 2002). Weberling (1989) described the ovary as being fundamentally gynobasic, although with an apical septum. There are a few, mostly old records of protein crystalloids in the nucleus (Speta 1977; Thaler 1966).

For Cuscuta, see Kuijt (1969) and Heide-Jørgensen (2008); Tiagi (1951) and Johri and Tiagi (1952) describe embryology, flower and fruit, Sherman et al. (2008), germination, Welsh et al. (2010), pollen, and Krause (2011), aspects of plastome evolution. For the diversity of style and stigma morphology in Cuscuta, which encompasses that of the whole family, see Wright et al. (2011).

For chemistry, see Hegnauer (1964, 1989), for seed reserves, see G. Dahlgren (1991), for the rpl2 intron, Downie et al. (1991) and Stefanovic et al. (2002), for a morphological phylogeny, see Austin (1998), for ovary morphology, see Deroin (1999b), for floral anatomy, Deroin (2004 and references), for embryology, see Kaur (1969) and Kaur and Singh (1970), for seed anatomy, see Kaur and Singh (1987), for the chloroplast ycf15 gene, see McNeal et al. (2007), for general information, see Staples and Brummitt (2007), for successive cambia, etc., see Rajput et al. (2008). Some other information about Humbertia is taken from Pichon (1947) and K. Kubitzki and H. Manitz (pers. comm.), but the genus is poorly known, especially embryologically.

Phylogeny. Within Convolvuloideae, part of Poraneae (Cardiochlamyeae: Porana itself is polyphyletic), Erycibeae s. str., and a clade made up of all other Convolvuloideae form a basal trichotomy. Cardiochlamyeae have foliaceous bracts and fruits that are utriculate, i.e. they are one-seeded and have a papery pericarp. Erycibe itself (= Erycibeae) has broad, radiate, sessile stigmas and a berry-like fruit; it can look very unlike other members of the family and herbarium specimens are often misidentified. Ipomoea, Convolvulus, and their relatives form an embedded clade that is sister to a rather unexpected clade made up of Poraneae, Cresseae, Dichondreae (with gynobasic styles), some Erycibeae (Maripeae), etc., as well as Jacquemontia. Several members of this latter clade have separate styles or only an at most short common style and long branches (but not Jacquemontia, etc., which have a long common style), and leaf blades with more or less pinnate venation; Jacquemontia could be sister to the other taxa. Despite the sequencing of over 6800 bp, the position of Cuscuteae remains unclear (Stefanovic & Olmstead 2001, 2004; Stefanovic et al. 2002 and esp. 2003), however, they may be close to a clade containing species with bifid styles (Wight et al. 2011).

For relationships within Cuscuta, see e.g. Stefanovic et al. (2007), García and Martín (2007), and Stefanovic and Costea (2008). Species limits in Cuscuta are difficult (Costea & Stefanovic 2009); see Costea et al. (2011) and references for recent work on the genus.

Ipomoea is paraphyletic. Within it there is a well-supported spiny pollen clade that comprises some 50% of the larger Ipomoea clade (Manos et al. 2001a).

• Cuscuta is a morphologically distinctive parasite - it lacks internal phloem; the corolla is imbricate, with a fimbriate corona especially well developed below and adaxial to the stamens; (tapetum plasmodial); pollen (bi-)trinucleate; styles separate to connate, stigma capitate to elongated; ovules with integument 15-17 cells across, usu. vascularized, (incompletely) tenuinucellate, endothelium 0; megaspore mother cells several, competition between the developing embryo sacs (Sastri 1956), embryo sac bisporic, eight-celled [Allium type] (normal - monosporic, 8-celled); testa anatomy is like that of other members of the family, but the testa is not multiplicative; the embryo is spirally coiled and (almost) acotyledonous; there is no root or root cap.

Classification. For tribal groupings, see Staples and Brummitt (2007); for Cuscuta, see the Parasitic Plants website (Nickrent 1998 onwards) and the Digital Atlas of Cuscuta (Costea 2007 onwards).

SOLANACEAE Jussieu, nom. cons.   Back to Solanales

Herbs to shrubs, branching sympodial; hygroline alkaloids, (withanolides [steroidal lactones]), oligosaccharides, (myricetin) +; roots diarch [lateral roots 4-ranked]; (hairs branched/stellate); wood commonly fluoresces; pits vestured; crystal sand +, esp. in stem; cystoliths +; stomata various; leaves simple to compound; (branching/leaf insertion in inflorescence apparently deviating from normal); (flowers 4 merous; obliquely monosymmetric); anthers often dehiscing by pores, or ± connate and pollen exiting communal apical hole; tapetum cells often 4-nucleate; G [(-5)], oblique, often pseudo-4-locular, stigma capitate or peltate, wet; ovules usu. many/carpel, often campylotropous; embryo sac with chalazal haustorium; fruit a berry or septicidal capsule (drupe), K accrescent or not; exotestal walls thickened usu. on inner periclinal and anticlinal walls, endotesta [= endothelium] ± persistent, walls ± lignified; endosperm (helobial, nuclear) +, cotyledons and radicle same width; n = 7-14, etc., chromosomes 1-3 µm long, protein bodies in nuclei.

102[list]/2460 - 8 clades below, but treatment needs work. World-wide, but overwhelmingly tropical America (map: from van Steenis & van Balgooy 1966; Meusel et al. 1978; van Balgooy 1984; Heywood 2007). [Photos - Iochroma Flower, Przewalkskia Fruiting Calyx, Schizanthus Flower.]

1. Schizanthoideae Hunziker

Annual herbs; tropane alkaloids +; cork pericyclic; pericycle fibres 0; flowers strongly monosymmetric, abaxial pair of C connate, forming a keel; A 2 [abaxial-lateral], staminodes 3; fruit septicidal capsule; endosperm nuclear, embryo curved; n = 10.

1/12. Chile.

2. Goetzeoideae Thorne & Reveal

Trees to shrubs; fruit often a drupe; pollen tricolpate, exine echinate, tectum perforate; fruit:; endosperm at most slight, cotyledons large, fleshy [Goetzea, etc.]; n = 12, 13.

6/8. Most Greater Antilles, but not Jamaica, east Brazil, Madagascar (Tsoala). [Photo - Flower.]

Synonymy: Goetzeaceae Miers

3. Duckeodendron

Tree; wood with large, open, radial canals [cf. Apocynaceae s. str.]; 1 ovule/carpel; fruit a one-seeded drupe; endosperm slight, embryo U-shaped, cotyledons small.

1/1: Duckeodendron cestroides. Amazonian Brazil.

Synonymy: Duckeodendraceae Kuhlmann

4. Browallioideae Kosteletzky

(Steroid alkaloids - Cestrum); cork superficial or deep-seated; bordered pits +; pericyclic fibres +; A 4 or 5, often didynamous, staminode +/0; (fruit fleshy); exotestal cells somewhat thickened on all walls - Cestrum; n = (7-)11(-13), chromosomes 6-7 µm long.

10/210: Cestrum (175). South and Central (and North) America.

Synonymy: Cestraceae Schlechtendal, Salpiglossidaceae Hutchinson

5. Schwenckioideae

Annual herbs; pericycle fibres +; flowers monosymmetric, C lobes 3-lobed [Schwenckia and Melananthus]; A 4, didynamous, or 2 + 2 or 3 staminodes; embryo straight, short; n = 10, 12.

4/31. South America.

[Petunioideae [Nicotianoideae + Solanoideae]] (if this clade exists): (tropane alkaloids [calystegines] +).

6. Petunioideae

Cork superficial (deep-seated); bordered pits +; pericyclic fibres +(0); druses 0(+); (flowers monosymmetric); A 4(-5), usu. of two lengths; embryo also slightly curved; n = 7-11.

13/160: Brunfelsia (45). Central and South America.

[Nicotianoideae + Solanoideae]: (nicotine [pyridine alkaloid] +); stigma wet; (cotyledons accumbent); x = 12.

7. Nicotianoideae Miers

Cork superficial; pericyclic fibres +/0; A 4 (staminode +), 5, (of two lengths); embryo straight (curved), radicle short; n = (7-11).

8/125: Nicotiana (95), Petunia (35). Mostly Australian, also North and South America, Africa.

Synonymy; Nicotianaceae Martynov

6. Solanoideae Kosteletzky

(Small tree); (steroidal alkaloids +); pits not vestured; (crystal sand +) [level?]; A 5 (4), (of different lengths), base of the filament [stapet] often enlarged, with lobes, etc.; (style gynobasic; G 3, or subdivision of carpels into 1-seeded units - "Nolanaceae"); fruit a berry (drupe; circumscissile capsule - Hyoscyameae; schizocarp; K highly accrescent); seeds flattened; (exotestal cells anticlinally elongated); endosperm cellular, embryo curved, often coiled; (n = 10-15), chromosomes 1-14 µm long.

62/1940: Solanum (1250-1700), Lycianthes (200), Lycium (90), Nolana (90), Physalis (80). World-wide, but esp. South America and others N. temperate. [Photo - Flower.]

Synonymy: Atropaceae Martynov, Browalliaceae Berchtold & J. Presl, Daturaceae Berchtold & J. Presl, Hyoscyamaceae Vest, Lyciaceae Rafinesque, Nolanaceae Berchtold & J. Presl, nom. cons., Sclerophylacaceae Miers

• Solanaceae are quite often rather foetid herbs or weak shrubs with polysymmetric or weakly, rarely strongly, monosymmetric sympetalous flowers - when monosymmetrical, the flowers are held so that the odd or median petal is in the adaxial position. Vegetatively many Solanaceae - especially Solanoideae, the bulk of the family - are distinctive because the insertion of leaves, branches and flowers often does not seem to follow any regular sequence; paired leaves adjacent on the stem are common. The flowers often have anthers dehiscing by pores or the anthers as a group are connivent at the apex. The fruit is usually bicarpellate and is a septicidal capsule or a berry with flattened seeds; the calyx consists of connate sepals that persist and even enlarge in fruit.

Evolution. Divergence & Distribution. Stem group Solanaceae date from 66-65 million years before present, crown group (including Schizanthus and Duckeodendron) from 41-36 million years before present (Wikström et al. 2001); Janssens et al. (2009) date crown Solanaceae to 58±9.1 million years before present. A genome duplication event in Solanaceae has been dated from ca 50-52 million years before present (Schlueter et al. 2004), and Soltis et al. (2009) suggest that diversification in Solanaceae may be connected with this (they place the duplication as an apomorphy of the species-rich Solanoideae, although with some hesitation).

The age of the [Nicotianoideae + Solanoideae] clade has been estimated at ca 23.7 million years, that of Solanum (inc. tomato and eggplant) ca 15.5 million years (add Capsicum - ca 19.6 million years - see Wu & Tanksley 2010; see also Wang et al. 2008 for similar ages).

Solanaceae may be New World in origin, and there have been perhaps 8-9 dispersal events to the Old World (Tu et al. 2010). Dillon et al. (2009) discuss the evolution of Nolana, a speciose clade of the coastal deserts (lomas) of western South America, and perhaps originally from Peru.

Plant-Animal Interactions. New World Solanaceae are eaten by larvae of some 360 species of Nymphalidae-Danaeinae-Ithomiini (or Ithomiinae) butterflies; there seems to have been a switch of host plants from Apocynaceae (Ehrlich & Raven 1964; Drummond & Brown 1987; Willmott & Freitas 2006: Schizanthoideae, Goetzeoideae and Schwenkioideae may not be eaten). Although detailed coevolution seems not to be involved, the diversification rate of the butterflies seems to have temporarily increased with this shift (Fordyce 2010). This diversification began at middle elevations on the Andes in the middle Miocene, ca 15 million years ago, and Solanaceae are common along the Andes today (Elias et al. 2009). Solanum itself is especially important as a food source for caterpillars of this group (ca 70% records of neotropical Solanaceae food sources, ca 89% those of all Ithomiini: Willmott & Freitas 2006; see also Brower et al. 2006). Interestingly, it has been suggested that in the most diverse communities, most species of Solanaceae are eaten by ithomiine larvae, perhaps suggesting that the host plant niche is almost saturated (Willmott & Elias, in Elias et al. 2009). Some larvae may be distasteful because of the alkaloids, etc., of the leaves they eat, and Brown (1987) suggested that the noxious solanaceous chemicals also guide oviposition and the feeding preferences of the larvae: "Though the butterflies may be able to recognise their food plants, biologists have greater difficulty in Solanaceae identification" (Brown 1987, p. 373).

The adult butterflies are also distasteful, and this is not because of these alkaloids, but rather because of the dihydroxypyrrolizidines that the adults obtain especially from Apocynaceae, Boraginaceae-Heliotropioideae and Asteraceae-Asteroideae (especially Eupatorieae). The butterflies are initially quite palatable immediately after hatching, but that soon changes, and massive amounts (ca 20% dry weight) of these chemicals may be sequestered (Brown 1987). The mimicry rings in which Ithomiini are involved may be associated with particular solanaceous host plants (Willmott & Mallet 2004).

Tobacco hornworm caterpillars prefer members of the [Solanoideae + Nicotianoideae] clade as food sources, although they didn't like Nicandra much; they died on Petunia, and didn't grow on Browallia and Brunfelsia. Other plant feeders show similar distinctive patterns (e.g. Fraenkel 1959), thus other sphingids are found here and on Oleaceae (Forbes 1958). Phytophagous Chrysomelidae beetles (perhaps especially Criocerinae) are notably more common on New World than Old World Solanaceae, perhaps suggesting an origin of the use of the family as a food source in the former area (Jolivet & Hawkeswood 1995; see also Hsiao 1986), while Chrysomelinae and Megalpodinae are also found on New World Solanaceae (Jolivet 1988). Criocerinae may have moved onto Solanaceae from monocots; the larvae are covered by faecal shields (Vencl & Morton 1999). In general, however, Solanaceae have multiple lines of defence and are avoided by most insect herbivores (Harborne 1986; Hsiao 1986).

Touch-sensitive trichomes are common in Solanoideae (or they have simply been most studied there), and glandular hairs are common, as well as many other hair types (see Seithe 1962; Seithe & Sullivan 1990 and references for hair morphology, esp. in Solanoideae). Insect-deterrent secretions are produced when these hairs are brushed by the insect; these secretions may contain poisonous metabolites, or they may rapidly oxidise and become sticky, so trapping and killing small insects, or secretion in these hairs may hydrolyse, so attracting other insects that target the caterpillars eating the plant (van Dam & Hare 1998 and references; Kellogg et al. 2002; Weinhold & Baldwin 2011). Mutants of tomatoes lacking the protective metabolites have been found to be susceptibe to herbivory in the field (Kang et al. 2010).

Floral Biology & Seed Dispersal. Knapp (2010) summarises information on pollinators and basic floral morphology in the family. The complex flower of Schizanthus is described as having oblique rather than inverted symmetry (Cocucci 1989b) - functionally the two are equivalent - and dehiscence of the two functional anthers is explosive (Cocucci 1989a). For floral evolution in the genus, not very speciose, see Pérez et al. (2006: midpoint rooting), and for CYC gene expression, see Preston et al. (2011b). Within Solanoideae, the Andean Iochrominae are notably diverse florally and have a variety of pollinators (Smith & Baum 2006). Zygomorphy and heteranthy (which in this context is really a kind of zygomorphy) have evolved several time in Solanum (Bohs et al. 2007); buzz pollination is common there (see Teppner 2005 for the pollination of the tomato; Harter et al. 2002; García et al. 2008) with over a million pollen grains being produced by a single flower (Anderson & Symon 1988); the corolla is often rotate, the flowers lack nectar and the anthers dehisce by terminal pores, all features of buzz-pollinated flowers. Nierembergia (Petunioideae) has oil flowers (Coccucci 1991; see Tate et al. 2009 for a phylogeny). A number of taxa have quite large and complex stigmas (Cocucci 1991, 1995).

Seed dispersal very much follows what fruit morphology might suggest (Knapp 2002b for a summary); in the New World Solanum in particular is an important food source for Stumira, a phyllostomid bat (Lobova et al. 2009 for records). The distinctively pungent capsaicanoids of chilis (Capsicum spp.) are involved in the protection of the fruit against the fruit-destroying Fusarium fungus (Tewksbury et al. 2008).

Genes & Genomes. Wu and Tanksley (2010) have reconstructed the ancestral genome of the [Nicotianoideae + Solanoideae] clade, and the various changes involved in the genomes of Nicotiana, tomato, pepper, etc. One or more functional genes from Agrobacterium rhizogenes are found in many, but not all, species of Nicotiana and may have coevolved with the plant genome (Intrieri & Buiatti 2002). Indeed, horizontal gene transfer is relatively quite common in Solanaceae (Talianova & Janousek 2011).

Other. Petunia and Hyoscyamus, in different subfamilies, can be intergrafted (Taiz & Zeiger 2006).

Economic Importance. Chiles (Capsicum annuum were domesticated in Mexico, quite possibly in a number of places (Aguilar-Meléndez et al. 2009); other species of the genus are also economically important (Perry et al. 2007 and references); for the domestication of the tomato, see Bai and Lindhout (2007).

Chemistry, Morphology, etc. Lycium is recorded as accumulating glycine betaines, and some members at least are halophytic (Levin & Miller 2005). For alkaloids in Datureae, see Doncheva et al. (2006). Schizanthoideae have distinctive tropane alkaloids, hairs, and pollen (Hunziker 2001).

Unusual stomata with degenerate guard cells seem often to have been reported in the family (Cammerloher 1920; D'Arcy & Keating 1973). Leaves in the fertile part of the stem of Solanaceae, perhaps especially in Solanoideae, are often geminate and/or branching is not simply axillary; Petunia can have ordinary-looking cymose inflorescences, but Schwenkia, Schizanthus and many other taxa have more or less recaulescent bracts, only one branch of the cymose inflorescence is developed at each node, or the two branches develop in different ways, etc., making interpretation of the construction of the plant very difficult (see especially Danert 1958, 1967; Child & Lester 1991 for a brief summary; Bell & Dines 1995). However, Castel et al. (2010) cut through the typology and suggest similarities between inflorescences of at least members of Petunioideae and Solanoideae; they note that the absence of bracts here may be only apparent. Goetzea has an odd growth pattern; its leaves are rather xeromorphic.

For a survey of the considerable floral diversity in Solanaceae, see Knapp (2010). Physalis has notably inflated calyx surrounding the fruit in the development of which heterotopy of a foliar gene may be involved (He & Saedler 2007; cf. Hu & Saedler 2007); inflated calyces occur in some nine genera in total, although details of the pattern of evolution - and perhaps also loss - of this feature are unclear. In floral development, petal and stamen primordia together are lifted by zonal growth and the carpel primordia develop on a flat apex; in this respect there are some similarities between Solanaceae, Scrophulariaceae and Gesneriaceae, few with Montiniaceae (Huber 1980: 66-69; Ronse Decraene et al. 2000). For floral development in Datureae, see Yang et al. (2002). The flowers of Nolana have two long and two short stamens. The patterns of endothecial thickenings in the family are very diverse (Carrizo García 2002).

More or less well developed monosymmetry is quite common in Solanaceae, and is of the 3:2 sort (see Eichler 1875; Robyns 1931; Cocucci 1989; Knapp 2002a; Ampornpan & Armstrong 2002). Zygomorphy and heteranthy (which in this context is really a kind of zygomorphy) have evolved several time in Solanum (Bohs et al. 2007), and also occur in Sclerophylax, for example. The two carpels so common in Solanaceae (but Nicandra has 3-5 while and Nolana many more) are often in the plane of the first sepal initiated; this is one of the abaxial pair. Indeed, the basic plane of symmetry in flowers like Salpiglossis and Schizanthus may be monocotyledonous, and the "abaxial" one or three stamens are sterile. However, floral symmetry in both Convolvulaceae and Solanaceae needs study, especially given the suggestion by Ampornpan and Armstrong (2002) that in the latter the gynoecium is in the median plane, the parts being initiated slightly off the vertical plane of symmetry and the whole flower slightly rotated, the result being the odd petal comes to lie in the adaxial position. For a detailed study of the frequent loss of gametophytic incompatibility in Solanaceae, see Igic et al. (2006). Androgenesis, an uncommon condition in which the male gamete in maternal cytoplasm produces an embryo, has been recorded for at least one member of each of the three subfamilies Petunioideae, Nicotianoideae and Solanoideae - Petunia, Nicotiana, and Capsicum (Chat et al. 2003 for references).

Arabidopsis-type telomeres are absent from some Browallioideae (Sýkorová et al. 2003a). Cestreae in particular, which lack these telomeres, have chromosomes that at 7.21-11.51 µm long are considerably larger than those of the rest of the family, which are much smaller, e.g. 1.5-3.52 µm long in Nicotianoideae (Acosta et al. 2006; Tate et al. 2009); Cestreae also have n = 8 (Las Penas et al. 2006).

For general chemistry, see Hegnauer (1973, 1990, also 1966, 1990 as Nolanaceae) and for evolution of secondary metabolites, see Wink (2003 and references), for embryology, see di Fulvio (1969: Nolana) for seed coat morphology and development, see Souèges (1907: he described the chalazal end of the embryo sac as herniating), for wood anatomy, see Carlquist (1987, 1988a) and Jansen and Smets (2001: vestured pits - do Petunioideae and Nicotianoideae have them?), for floral development, see Sattler (1977), for floral and inflorescence morphology, see Huber (1980), for branching patterns, see Danert (1958), for pollen morphology of zygomorphic taxa, see Stafford and Knapp (2006: not yet integrated with phylogeny), and of Hyoscyameae, see Zhang et al. (2009), for evolution of fruit and flower types, etc., see Knapp (2002) and Knapp et al. (2004), for calystegines (tropane alkaloids), see Dräger (2004), for the evolution of floral scent, see Martins et al. (2007), for fruit anatomy, see Pabon Mora and Litt (2007), for floral vascularization, see Liscovsky et al. (2009 and references), for chromosome numbers in Solanoideae, see Chiarini et al. (2010). For details of the distinctive Sclerophylax, see di Fulvio (1961).

Phylogeny. For early studies of relationships, see Olmstead & Palmer (1992) and Fay et al. (1998b). The grouping [Petunioideae [Solanoideae + Nicotianoideae]] is well supported in Olmstead et al. (1999), although less so in Olmstead and Santiago-Valentin (2003). However, in the summary tree of Olmstead and Bohs (2007), although there is a clade [Solanoideae + Nicotianoideae], immediately below it is a polytomy including Petunioideae, Cestroideae and Schwenkioideae (see Dillon et al. 2009 for another topology). Indeed, the relationships between the branches basal to this group have only weak support, Schwenkia may be sister to the rest of the family (Olmstead et al. 1999). However, using the nuclear gene SAMT (salicylic acid methyl transferase), Martins and Barkman (2005) found Schizanthus to be sister to the rest of the family, and with rather strong support, with Schwenkia weakly linked with Cestroideae (see also Olmstead & Bohs 2007). The Goetzioideae clade in the past has included Duckeodendron as sister to the rest, but with only moderate support (Santiago-Valentin & Olmstead 2001, 2003); here its relationships are unresolved. Furthermore, Wu et al. (2006) found a strongly supported grouping of [Solanoideae [Petunioideae + Nicotianoideae]], and although in this case no other clades of the family were included, Wu et al. (2006) noted that the sequences they included came from ten orthologous loci each on a different chromosome. (Wu et al. [2006] also dismissed the possibility that there had been a genome duplication either on the branch leading to Solanaceae or within Solanaceae themselves [cf. Blanc & Wolfe 2004].) The two-gene tree in a recent study by Olmstead et al. (2008) is rather like that of Martins and Barkman (2005), with relationships as follows: Schizanthoideae [Goetzioideae, Duckeodendron [[Cestroideae/Browallioideae, including Benthamiella et al.; their relationships have previously been unclear], Petunioideae, Schwenckioideae [Nicotianoideae + Solanoideae]]], but there is strong support for relationships between the last pair of taxa alone. The distinctive Sclerophylax is included in Solanoideae (Olmstead et al. 2008) - it has sessile flowers, an inferior obliquely-oriented ovary with 2-3 ovules per carpel that are pendulous from the upper part of the loculus, and the calyx is accrescent, spinescent, and surrounds the 1-3-seeded fruit. Clearly there remain substantial uncertainties about relationships between major groupings within the family, and the account above is notably imperfect.

Within Solanoideae, the limits of Solanum are to be expanded to include Cyphomandra and Lycopersicon; the hairs are often stellate and prickles are common (see Bohs 2005, 2007; Levin et al. 2006; Weese & Bohs 2007 [three genes, S. thelopodium sister ro rest, or unresolved in Bayesian analysis], Botany 2008: Botany without Borders 120-121. 2008; Poczai et al. 2008, for phylogenies). Relarionships within the speciose subgenus Leptostemon, characterised by stellate hairs and prickles, are outlined by Stern et al. (2011). Jaltomata is sister to Solanum; major clades in that geneus are characterised by fruit colour (Miller et al. 2011). For relationships within the distinctive Nolana, in the past often separated and placed in Nolanaceae because of its gynoecium, see Tago-Nakawaza and Dillon (1999), Dillon et al. (2007, 2009) and Tu et al. (2008).

Lycium may be paraphyletic, and then will need to be expanded to include Phrodus and Grabowskia (Levin & Miller 2005; Levin et al. 2007; Levin et al. 2009).

Classification. For generic descriptions and much else, see Hunziker (2001), although his suprageneric classification differs from that used here; Solanaceae Source includes information currently mostly about Solanum, but its coverage will expand. For the main outlines of the classification followed here, see Olmstead et al. (2008). For the circumscription of Lycium, see Levin et al. (2011).

Previous Relationships. Huchinson (1973) placed Duckeodendraceae in Boraginaceae, but doubtfully; Cronquist (1981) kept it as a poorly-known family; Takhtajan (1997) placed it as a separate family in Solanales. Its carpels are oblique to the main axis of the flower (Kuhlmann 1934), as is appropriate for a genus in Solanaceae. Nolanaceae have often been separated from Solanaceae on account of their distinctive gynoecium; there are basically five carpels borne opposite the petals, but their number secondarily increases; the basic growth pattern is very like that of other Solanoideae (see also Eichler 1874).