EXTANT SEED PLANTS

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 rich in guaiacyl units; true roots present, apex multicellular, xylem exarch, 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 +; tracheid/tracheid pits circular, bordered; sieve tube/cell plastids with starch grains; phloem fibers +; stem cork cambium superficial, root cork cambium deep seated; nodes ?; stomata ?; leaf vascular bundles collateral; leaves spiral, simple, axillary buds?, prophylls [including bracteoles] two, lateral, veins -5 mm/mm² [mean for all non-angiosperms 1.8]; 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, 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 duplication [N/O//A/C and P//BE lines], 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 in ANITA grade?], 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 a sieve plate and cytoplasm with P-proteins, companion cells from same mother cell that gave rise to the sieve tube; nodes unilacunar [1:?]; stomata with ends of guard cells level with pore, paracytic, outer stomatal ledges producing vestibule; leaves with petiole and lamina [the latter 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; flowers perfect, polysymmetric, parts spiral [esp. the A], free, development in general centripetal, numbers unstable; P not sharply differentiated, outer members not enclosing the rest of the bud, smaller than inner members; A many, 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, walls developing by centripetal furrowing; pollen subspherical, binucleate at dispersal, trinucleate eventually, 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, few [?1] ovules/carpel, ovules marginal, anatropous, bitegmic, [outer integument often largely subdermal in origin, inner integument dermal], micropyle endostomal, integuments 2-3 cells thick, megasporocyte single, megaspore lacking sporopollenin and cuticle, chalazal, female gametophyte four-celled [one-modular, nucleus of egg cell sister to one of the polar nuclei], stylulus short, hollow, stigma ± decurrent, dry [not secretory]; P deciduous in fruit; seed exotestal; pollen germinating in less than 3 hours, tube elongated, growing at 80-600 µm/hour, with callose plugs and callose-based walls, penetrating between cells, siphonogamy, penetration of ovules within ca 18 hours, distance to first ovule 1.1.-2.1 mm; 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, minute; 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 + C/PHYB + E gene pairs.

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, because some taxa basal to the [magnoliid + monocot + eudicot] group have been surprisingly little studied, there is considerable variation between families 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....

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

VITALES + ROSIDS: anthers articulated [± dorsifixed, transition to filament narrow, connective thin].   Back to Main Tree

Evolution. Using penalized likelihood, Wang et al. (2009: two estimates) suggested that the Vitaceae/rosid split occured (115-)111, 92(-88) million years ago.

For the possible palaeohexaploidy of Vitales, see Jaillon, Aury et al. (2007). If this is a feature of rosids as a whole, then by the time one gets to genera like Brassica and Arabidopsis, the genome will have duplicated many, many times... Although it has more recently been suggested that there has been gene duplication, possibly because of hybridization, within the Vitis lineage itself, apparently bringing the whole Vitis genome more into line with that of other rosids (Velasco et al. 2007), Freeling et al. (2008: the Carica papaya genome was included in their study) suggest that most rosids, i.e. the node [Vitales + rosids s. str], are indeed palaeohexaploids in which two of the three genomes involved have lost notably more ancestral genes than the other (see also Tang et al. 2008a, b; Diaz-Riquelme et al. 2009 for possible genome duplications at this node).

Phylogeny. Molecular data still do not link Vitaceae unambiguously with any other single core eudicot order, but they are definitely not nested within any 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 probability 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 Dilleniales page for further discussion on the relationships of Vitales. The placement adopted here, although somewhat tentative, seems quite likely.

VITALES Reveal  Main Tree, Synapomorphies.

Vessel elements with simple perforation plates; tension wood 0; nodes 3-7:3-7; sieve tube plastids with protein crystalloids and starch; raphide bundles +; food bodies [pearl glands] +; leaves with glandular teeth; stamens = and opposite petals and from a common primordium, 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: Leeales de Candolle - Vitanae Reveal

VITACEAE Jussieu, nom. cons.   Back to Vitales

Ellagic acid, myricetin +; (cork cambium 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, stamens adnate to corolla, 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 Dumortier, nom. cons.

2. Vitoideae 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 two-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.

Evolution. The distinctive seeds of Vitaceae are found fossil quite commonly in both North America and Europe, although they are not known from the Cretaceous; there may be more than twelve seeds per berry, which suggests a gynoecium unlike that of any extant member of the family (Manchester & Chen 2009).

Caterpillars of some lepidoptera are found on Vitaceae and Onagraceae alone (Forbes 1956) - and both contain raphides. The raphides of Vitis are bipartite, square in transverse section, and like an arrow-head in longitudinal section (Horner & Wagner 1995). Food bodies, often called pearl glands, are common on the surface of the plant. They are multicellular, with a multiseriate stalk, sometimes with a stoma on the swollen head, and the central parenchymatic cells accumulate oils and sugars (Pavia et al. 2009).

Tetrastigma in West Malesia is the only host of the giant parasite Rafflesia (Rafflesiaceae, Malpighiales).

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).

Vitis, at least, has a massive mitochondrial genome largely as the result of the the expansion of intergenic spacers; there is the possibility of the migration of some DNA from the mitochondrion - very unusual - to the chloroplast here (Goremykin et al. 2009a).

Chemistry, Morphology, etc. 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 to a nectary (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.

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 general summary, see Wen (2006, as Leeaceae and Vitaceae).

Phylogeny. Ingrouille et al. (2002) in a study of rbcL phylogeny considered in the context of morphological variation found little strong support for clades within Vitaceae. 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 (Rossetto et al. 2002; Wen et al. 2007; Wen 2008).

Classification. Although Vitis and relatives and Leea are morphologically distinguishable, there are numerous features that unite the two and they are sister taxa in all phylogenetic studies; inclusion in a single family seems reasonable. The two agree in numerous features (see above), and the wood anatomy of Leea and Rhoicissus in particular is very similar. Generic limits in Viticoideae need attention, for example, species of Cissus occur all over the tree.

Previous Relationships. 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 also have stamens opposite their tepals, but are otherwise very different.