EXTANT SEED PLANTS

Plant woody, evergreen; nicotinic acid metabolised to trigonelline; primary cell walls rich in xyloglucans and/or glucomannans, 25-30% pectin [Type I walls]; lignins rich in guaiacyl units; true roots present, xylem exarch; shoot apical meristem complex; arbuscular mycorrhizae +; stem with ectophloic eustele, endodermis 0, xylem endarch; vascular tissue in t.s. discontinuous by interfascicular regions; vascular cambium + [xylem ("wood") differentiating internally, phloem externally]; wood homoxylous, tracheids +; tracheid/tracheid pits circular, bordered; sieve tube/cell plastids with starch grains; phloem fibers +; stem cork cambium superficial, root cork cambium deep seated; nodes ?; leaf vascular bundles collateral; leaves spiral, simple, axillary buds?, prophylls [including bracteoles] two, lateral; plant heterosporous, sporangia eusporangiate, on sporophylls, sporophylls aggregated in indeterminate cones/strobili; true pollen [microspores] +, mono[ana]sulcate, pollen exine and intine homogeneous, ovules unitegmic, crassinucellate, megaspore tetrad tetrahedral, only one megaspore develops, megasporangium indehiscent; male gametophyte development endo/exosporic, gametes two, with cell walls; 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 duplication, mitochondrial nad1 intron 2 and coxIIi3 intron present.

MAGNOLIOPHYTA

Plant woody, evergreen; lignans, O-methyl flavonols, dihydroflavonols, triterpenoid oleanane, non-hydrolysable tannins, quercetin and/or kaempferol +, apigenin and/or luteolin scattered, cyanogenesis via tyrosine pathway, lignins derived from both coniferyl and sinapyl alcohols, containing syringaldehyde [in positive Maüle reaction, syringyl:guaiacyl ratio less 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; stem with 2-layered tunica-corpus construction; wood fibers and wood parenchyma +; reaction wood ?, with gelatinous fibres; starch grains simple; primary cell wall mostly with pectic polysaccharides; tracheids +; sieve tubes eunucleate, with sieve plate, companion cells from same mother cell that gave rise to the tube, the sieve tube with P-proteins; nodes unilacunar; stomata with ends of guard cells level with aperture, paracytic; leaves with petiole and lamina [the latter formed from the primordial leaf apex], development of venation acropetal, 2ndary veins pinnate, fine venation reticulate, vein endings free; flowers perfect, polysymmetric, parts spiral [esp. the A], free, numbers unstable, P not differentiated, outer members not enclosing the rest of the bud, A many, development centripetal, with a single trace, introrse, filaments stout, anther ± embedded in the filament, tetrasporangiate, dithecal, 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, pollen subspherical, binucleate at dispersal, trinucleate eventually, tectum continuous, endexine compact, lamellate only in the apertural regions, pollen tube elongated, with callose plugs, penetrating between cells, growth rate moderate, siphonogamy occuring, nectary 0, G free, several, ascidiate, with postgenital occlusion by secretion, few [?1] ovules/carpel, ovules marginal, anatropous, bitegmic, micropyle endostomal, integuments 2-3 cells thick, megasporocyte single, megaspore lacking sporopollenin and cuticle, chalazal, female gametophyte ?type, stylulus short, stigma ± decurrent, wet [secretory]; P deciduous in fruit; seed exotestal; double fertilisation +, endosperm ?diploid, cellular [first division oblique, micropylar end initially with a single large cell, chalazal end more actively dividing], copious, oily and/or proteinaceous, embryo cellular ab initio; germination hypogeal, seedlings/young plants sympodial; Arabidopsis-type telomeres [(TTTAGGG)_n]; whole genome duplication, 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 PHYA/PHYC gene pairs.

Possible apomorphies are in bold. Note that the actual level to which many of these features, particularly the more cryptic ones, should be assigned is unclear, because some taxa basal to the [magnoliid + monocot + eudicot] group have been surprisingly little studied. Furthermore, details of relationships among gymnosperms will affect the level at which some of these characters are pegged.

NYMPHAEALES [AUSTROBAILEYALES [[CHLORANTHALES + MAGNOLIIDS] [MONOCOTS [CERATOPHYLLALES + EUDICOTS]]]]: vessels +, elements with scalariform perforation plates; pollen tectate-columellate, tectum reticulate [perforated]; nucleus of egg cell sister to one of the polar nuclei; ?genome duplication; "DEAER" motif in AP3 and PI genes lost, gaps in these genes.

PROTEALES [TROCHODENDRALES [BUXALES [GUNNERALES + CORE EUDICOTS]]]: ?

TROCHODENDRALES [BUXALES [GUNNERALES + CORE EUDICOTS]]: benzylisoquinoline alkaloids 0; euAP3 + TM6 genes [duplication of paleoAP3 gene: B class], mitochondrial rps2 gene lost.

BUXALES [GUNNERALES + CORE EUDICOTS]: ?

GUNNERALES + CORE EUDICOTS: Ellagic and gallic acids common, cyanogenesis via phenylalanine, isoleucine or valine pathways; micropyle?; PI-dB motif +, small deletion in the 18S ribosomal DNA common.

CORE EUDICOTS: Root apical meristem closed; flowers rather stereotyped: 5-merous, parts whorled, K and C distinct, K with 3 traces, A = 2x K, internal to the C whorl, (numerous, but then often fasciculate and/or centrifugal), pollen tricolporate, (nectary disc +), [G 5], [3] also common, compitum +, placentation axile, stigma not decurrent; endosperm nuclear; fruit dry, dehiscent, loculicidal [when a capsule]; euAP1 + euFUL + AGL79 genes [duplication of AP1/FUL or FUL-like gene], PLE + euAG [duplication of AG-like gene: C class], SEP1 + FBP6 genes [duplication of AGL2/3/4 gene].

SAXIFRAGALES [VITALES + ROSIDS]: Stipules +.

Vitales + rosids: Anthers articulated [± dorsifixed, transition to filament narrow, connective thin].   Back to Main Tree

For possible palaeohexaploidy of Vitales, see Jaillon, Eury et al. (2007). If this is a feature of rosids as a whole, then by the time one gets to genera like Brassica and Araabidopsis, the genome will have duplicated many, many times... However, it has more recently been suggested that there has been gene duplication, possibly because of hybridization, in the Vitis lineage itself, bringing the whole Vitis genome more into line with that of other rosids (Velasco et al. 2007).

The affinities of Vitaceae have long been uncertain. They were often associated with Rhamnaceae, since both have stamens opposite the petals, and Takhtajan (1997) placed them near Proteanae, in his Rosidae; Proteanae have stamens opposite their tepals, but are otherwise very different. Molecular data do not link them unambiguously with any other core eudicot, and they are definitely not nested high in the group. They were placed sister to rosids, but with only moderate support (D. Soltis et al. 2000), and even this moderate support weakened in a subsequent four-gene analysis (D. Soltis et al. 2003a); however, Jansen et al. (2006a, b) using complete chloroplast genome sequences found quite strong support for this position (note that members of Berberidopsidales, Dilleniales, Santalales and Saxifragales were not included: see also Ruhlman et al. 2007; Jansen et al. 2007; Moore et al. 2007). Hilu et al. (2003: matK analysis [incomplete sequence] alone) suggest relationships between Vitales and Dilleniales (only moderate support in parsimony analysis, but 100% posterior probabilities in Bayesian analyses), the combined clade being just above Malpighiales and below Saxifragales in a pectinate tree of major clades within the core eudicots. Although this relationship was not recovered in the analysis of the matK gene by Worberg et al. (2007), the two do have a similar and rather distinctive testa anatomy (see also Kubitzki 2006a). See the Berberidopsidales page for further discussion on relationships of Vitales, which still have no firm position, although the placement adopted here seems quite likely.

VITALES Reveal  Main Tree, Synapomorphies.

Vessel elements with simple perforations; tension wood 0; nodes 3-7:3-7; sieve tube plastids with protein crystalloids and starch; raphide bundles +; pearl glands + [multicellular, spherical, with an apical stoma]; leaves with glandular teeth; A = and opposite C, nectary gynoecial, 2 apotropous ovules/carpel, micropyle?, style +, short; fruit a berry, K deciduous; seeds perichalazal, vascular bundle ± surrounding seed, ± ruminate, testa multiplicative, exotesta fleshy, mesotesta 2-17 layers across, endotesta 2-5-layered, lignified, crystalliferous, exotegmen (crossed) tracheidal; embryo minute.

Wikström et al. (2001) suggest that the clade originated 117-108 million years before present and the crown group started diverging 92-78 million years before present.

Includes Vitaceae.

Synonymy: Vitanae Reveal

VITACEAE Jussieu, nom. cons.   Back to Vitales

Ellagic acid, myricetin +; (cork deep-seated); cambium storied; wood with broad rays; nodes often swollen; petiole with ring of bundles; stomata variable; branching from previous flush; (pearl glands 0); leaves palmately compound or -veined, conduplicate; inflorescences paniculate-corymbose; flowers small, (3-)5(-7)-merous, K connate, C valvate, micropyle endo(bi)stomal, nucellar cap +, placental obturator + or 0, stigma capitate or 4-fid, dry; prominent raphe and chalazal knot, seed-coat ingrowths delimiting raphe, (endotesta palisade).

14/850 - 2 groups below. Pantropical and (warm) temperate.

1. Leeoideae Burmeister

Herbs to trees; raphides barbed; leaves spiral, teeth with small glandular apex, one lateral vein continues its course above the tooth, stipules borne along petiole margin, sheathing; inflorescence terminal; C basally connate, A adnate to C, connate, with a lobed tube, nectary disc 0, G [3 (4)], (semi-inferior), odd member abaxial, loculi divided; rarely raphides in the seed coat; n = (10-)12.

1[list]/34. Most Indo-Malesian, few Africa and Madagascar (Map: from Ridsdale 1976). [Photo - Flower]

Synonymy: Leeaceae (Candolle) Dumortier, nom. cons.

2. Viticoideae Eaton

Vines or lianes (stout trees, herbs; rootstock swollen) climbing by leaf-opposed tendrils; raphides smooth; (cuticle waxes as tubular rodlets); leaves opposite, spiral or 2-ranked, teeth with gland broadening distally and with foramen, veins from above and below; inflorescences leaf-opposed (terminal); (C connate by papillae and calyptrate), (tapetum plasmodial), disc annular or as five glands, (investing G; 0), G [2], transverse or vertical, (style long); raphides in the seed coat; n = 10-16, 19, 20.

14[list]/825: Cissus (350), Cyphostemma (150: ?= Vitis), Ampelocissus (100), Tetrastigma (95), Vitis (65), Cayratia (65). Pantropical and (warm) temperate (Map: from Wickens 1971; Morley and Toelken 1983; Lombardi 2000; FloraBase 2006, still a lot to do). [Photo - Flower]

Synonymy: Ampelidopsaceae Kosteletzky, Cissaceae Horaninow, Pterisanthaceae J. Agardh

• Vitaceae may be recognised by their caducously stipulate leaves with palmately compound, -lobed or -veined blades and often rather coarse teeth, cymose inflorescences, and smallish flowers with valvate petals. The stamens are equal in number to and opposite the petals, the usually 4-ovulate, bicarpellate gynoecium has more or less sessile stigmas, and the berry often has ruminate seeds. The stems are often strongly lenticellate, with the bark ultimately flaking, and the leaf blades are very brittle when dry, the fine details of the venation being obscure. Leaf-opposed tendrils or inflorescences are common in the family. Even individual seeds are distinctive, the endosperm being T-shaped in transverse section, the arms often being incurved.

Some caterpillars are found both on Vitaceae and Onagraceae (Forbes 1956) - and both contain raphides.

Although Vitis and relatives and Leea are morphologically distinguishable, there are numerous features that unite the two; inclusion in a single family seems resaonable. The two agree in having a common corolla-stamen primordia (as do Rhamnaceae!). Phloem plastids and testa anatomy are also similar, and the wood anatomy of Leea and Rhoicissus in particular is very alike.

The tendrils are clearly stem structures, and some are replaced by inflorescences in fertile shoots (and part tendril-part inflorescences are not uncommon! - Calonje et al. 2002 for development). In some species not all leaves have axillary buds, and there has been discussion as to whether the inflorescence/tendril is an evicted terminal shoot, or not (Wilson et al. 2002, and references). In temperate Vitaceae there is pronounced vessel dimorphism while in tropical members of the family there is often distinctive cambial structure and hence secondary thickening patterns. The raphides of Vitis are bipartite, square in transverse section and like an arrow-head in longitudinal section (Horner & Wagner 1995). Flowers have a common stamen-petal primordium. There is considerable variation in nectary morphology, from enveloping the ovary and forming little projections on top to being absent. Although Leea lacks an obvious nectary like that of Vitis, etc., developmental data show that the lobes on the staminal tube are comparable (Gerrath et al. 1990). The ovary has been described as being "anatomically parietal" (Brizicky 1965, for references). The egg apparatus of Cissus is reported to lie outside the ovule (Nair 1970 for references). The raphe in the seed is flanked by a deep groove.

Ingrouille et al. (2002) in a study of rbcL phylogeny considered in the context of morphological variation found little strong support for clades. Subsequent studies using more genes (e.g. Soejima & Wen 2006) find somewhat more resolution, although support values and relationships of the clades other than the Cyphostemma-Cayratia-Tetrastigma clade are still rather uncertain. It is clear that generic limits need attention, with e.g. species of Cissus occuring all over the tree (Rossetto et al. 2002; Wen et al. 2007).

Some general information is taken from Lombardi (2000); for vascular anatomy, see Wheeler and LaPasha (1994), for nodal anatomy and stipules, see Shah (1959), for phyllotaxis, Gerrath et al. (1998), for leaf teeth, Hickey and Wolfe (1975), for floral development, see Gerrath and Posluszny (1989 and references - Viticoideae) and Timmons et al. (2007: some Viticoideae, useful table), and Gerrath et al. (1990 - Leeoideae), for embryology, etc., see Nair (1970), for seed anatomy in extant and fossil taxa, see Chen and Manchester (2007), and for a recent summary, see Wen (2006, as Leeaceae and Vitaceae).