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].

ASTERIDS - Sympetalae redux?: Nicotinic acid metabolised to its arabinosides; (iridoids +); tension wood decidedly uncommon; C sympetalous, if evident only early in development, petals free, anthers dorsifixed?, (nectary gynoecial), ovules unitegmic, integument thick, endothelium +, nucellar epidermis does not persist, style +, long; seed exotestal; endosperm cellular, embryo long.

ERICALES + ASTERIDS I + II: (C tube in flower), ovules tenuinucellate.

ASTERIDS I + II: ellagic acid 0, proanthocyanidins not common; inflorescence cymose; C forming a tube, A epipetalous, = and opposite K or P [polyandry (secondary) very uncommon indeed].

ASTERIDS II: Myricetin 0; vessel elements with scalariform perforations; flowers rather small, style short; endosperm copious, embryo short/very short.

ASTERALES [APIALES + DIPSACALES]: iridoids +; C tube initiation early, G [2-3], inferior.

APIALES + DIPSACALES: ?

[Paracryphiaceae + Quintiniaceae + Sphenostemonaceae] DIPSACALES]]: nodes 3:3; true tracheids +; leaves serrate; inflorescence terminal.

Paracryphiaceae + Quintiniaceae + Sphenostemonaceae: leaves spiral; inflorescence racemose; flowers 4-merous; capsule septicidal.

For the placement of the following three families, see Winkworth et al. (2008). They also form a clade in Lundberg's three-gene Bayesian analysis (Lundberg 2001e); Cameron (2001, see also 2003) also suggested an association between Paracryphiaceae and Sphenostemonaceae. The vessel elements of the three are very long and the perforation plates have many bars (aspects of the wood anatomy of Paracryphiaceae have previously been considered to be among the most primitive in angiosperms...). The three are morphologically rather different so they are characterised separately below. Sphenostemonaceae and Paracryphiaceae are two of the few asterid I + II taxa which sometimes have more than twice as many stamens as petals; here the perianth is either uniseriate and/or or decussate.

In earlier versions of this site (pre April 2008), [Columelliaceae + Desfontainiaceae} were placed sister to Dipsacales, with which they do show considereble morphological similarity. However, recent work suggests they are associated with Bruniaceae, and in turn sister to either Asterales or [Dipsacales + Apiales] (Winkworth et al. 2008a).

PARACRYPHIACEAE Airy-Shaw   Back to Unplaced

Woody; chemistry?; petiole bundle flattened-annular, with medullary bundles; styloids +; hairs unicellular; inflorescence branched-spicate, plant andromonoecious; P (5), decussate-cochleate, caducous, A 8(-11), filaments stout, thecae ± embedded in connective, nectary 0, G [8-15], attached to central tissue, 4 crassinucellate ovules/carpel, stigmas central, separate, conduplicate; fruit with carpels pulling away acropetally and opening adaxially, columella persistent; seeds winged, exotesta? with sinuous anticlinal walls, inner walls lignified; embryo size?, radicle relatively long; n = ?

1[list]/1: Paracryphia alticola. New Caledonia.

The family was included in Theales by Cronquist (1981), in Theanae by Takhtajan (1997). It was linked quite strongly with Rutaceae + Meliaceae + Simaroubaceae by Källersjö et al. (1998), but cf. Savolainen et al. (2000a).

Some information is taken from Dickison and Baas (1977) and Lundberg (2001e).

Synonymy: Paracryphiales Reveal

QUINTINIACEAE Doweld   Back to Unplaced

Trees; plants Al accumulators, group 1 secoiridoids, ellagic acid +; vessels vestured; petiole bundle?; glands peltate; (leaf margins entire); flowers also 5-merous, C free, anthers ± basifixed, placentoid ?, pollen 4-6 colporate, G [3-5], nectary +, placentation parietal or axile, many bitegmic ovules/carpel, micropyle endostomal, style long, stigma lobed, wet; K persistent; micropylar haustoria ?; n = ?22.

1/25. Philippines and New Guinea to New Zealand and New Caledonia (Map: from Heywood 2007, in part).

• Quintiniaceae are evergreen trees or shrubs with spiral, serrate, estipulate leaves; the plant is covered with peltate scales. The inflorescence is terminal and the flowers have free sepals and petals and an inferior ovary. The fruit is a septicidal capsule.

Quintinia is almost unknown embryologically. The placentation is perhaps fundamentally parietal (Bensel & Palser 1975b); the ovules may be bitegmic (Mauritzon 1933; Philipson 1974), but this needs confirming. Much information is taken from Lundberg (2000d).

Synonymy: Quintiniales Doweld

SPHENOSTEMONACEAE P. van Royen & Airy Shaw   Back to Unplaced

Evergreen shrubs or trees; iridoids?; phloem stratified; petiole bundles three, arcuate, or annular with wing bundles; styloids + or 0; hairs unicellular; leaves (subopposite), margins toothed (entire), stipules cauline, minute; K and C decussate, free, or C 0, A = and opposite K-12, filaments stout, thecae ± embedded in connective, pollen por(or)ate, G [2], 1(2) pendulous ovule/carpel, funicular obturator +, endothelium?, style 0, stigma large, capitate; fruit a berry; seeds ruminate or not, exo- or exoendotestal, endotestal cells with dark contents; embryo short?; n = ?

1[list]/10. New Guinea, Australia (Queensland) and New Caledonia (Map: from van Balgooy 1984; Mark Newman, pers. comm.).

• Sphenostemonaceae are usually small, evergreen trees with spiral, strongly serrate, estipulate leaves and terminal inflorescences of rather small flowers. The sepals and petals are free, the anther thecae are borne on stout filaments, and there is no style; the fruit is fleshy and two-seeded.

The fruit is often described as being a drupe, but Lundberg (2001c) described the fruit as being a pseudo-drupe (and the seeds as being pachychalazal), while Savinov (2003) described the fruit as being a berry. The family is poorly known. Styloids are visible on the abaxial surface of the lamina of Papuasian species; they look rather like cystoliths.

Baas (1975) thought that Sphenostomonaceae and Phellinaceae were members of Celastrales, close to Icacinaceae; Takhtajan (1997) included them in Icacinales.

See also Jéremie (1997) for general information, Savinov (2003) for fruit and seed anatomy.

Synonymy: Sphenostemonineae I. Savin., Sphenostemonales Doweld

DIPSACALES Dumortier  Main Tree, Synapomorphies.

Route I secoiridoids +; cork deep-seated; pericyclic fibers 0; petiole bundles arcuate; buds with scales; leaves opposite, bases ± confluent, margins gland-toothed; inflorescence cymose; pollen grains trinucleate, G ± inferior; K persistent in fruit; testa vascularised, exotestal cells enlarged (palisade), variously thickened and lignified. - 2 or 7 families, 45 genera, 1090 species.

The first split within crown Dipsacales may have occured in the mid-Cretaceous, some 111-93 million years before present, 20-30 million years older than some estimates (Bell & Donoghue 2005a and references). However, major diversification within Dipsacaceae and Valerianaceae - and hence a major part of the diversification of the whole order - is relatively recent, occuring within perhaps ca 10 million years (Bell & Donoghue 2005a). For a very detailed discussion of morphological evolution, see Donoghue et al. (2003). Howarth and Donoghue (2004, esp. 2005) noted intriguing correlations between duplications with possible neofunctionalisation of CYC-like genes and changes in floral form in the order, although direct connections between changes both in morphology and in diversification rates remain to be established, indeed, diversification often seemed to increase as plants moved into new geographical area, especially if these were mountainous (Moore & Donoghue 2007).

Anthocyanin variation does not allow a sharp distinction between Caprifoliaceae and Adoxaceae (Jordheim et al. (2006). Involute ptyxis is more common in Adoxaceae than in Caprifoliaceae (Cullen 1978). Weberling (1957) discussed the morphology of the stipule-like structures and amplexicaul leaves in Caprifoliaceae and Adoxaceae; amplexicaul leaves in particular occur in several families in the order. Weberling (1989) also described the inflorescence structure, emphasizing the woody Dipsacales, in considerable detail. The morphology of the basic nectary type for the order remains unclear. In Viburnum (and Sambucus?) it is a disc-like structure on top of the inferior ovary, in Adoxa it is associated with multicellular hairs on the corolla, in Caprifoliaceae, unicellular hairs (Takhtajan 1997). For variation in floral anatomy, which clearly separates two groups of genera in the old Caprifoliaceae, see Wilkinson (1949 and references). There is considerable variation in the presence of the mitochondrial coxII.i3 intron.

The order has strong support in D. Soltis et al. (2000), Adoxaceae also being included (see also Wagenitz 1997; Bremer et al. 2001; cf. A.P.G. 1998). The phylogeny of the expanded order is based especially on work by Donoghue et al. (2001b, 2003), Zhang et al. (2003), Davis et al. (2001), Bell (2003) and Moore and Donoghue (2007). There are some (not major) disagreements with the phylogeny in Pyck and Smets (2001), while Judd et al. (1994) provide an early morphological analysis which gives a similar topology. Note that the position of Heptacodium was initially somewhat uncertain (Pyck & Smets 2000, 2001), although it is probably to be included in Caprifoliaceae s. str (e.g. Donoghue et al. 2001a, 2003). Valerianaceae are sister to the rest of the Caprifoliaceae s. str. part of the clade in some analyses (Soltis et al. 2007a), while analyses of mitochondrial data are perhaps particularly challenging (Winkworth et al. 2008b).

Takhtajan (1997) included Dipsacales, Adoxales and Viburnales in his Dipsacanae.

Includes Adoxaceae, Caprifoliaceae, Diervillaceae, Dipsacaceae, Linnaeaceae, Morinaceae, Valerianaceae.

Synonymy: Adoxales Nakai, Caprifoliales Lindley, Lonicerales T. Leibe, Viburnales Dumortier - Dipsacanae Takhtajan - Caprifoliopsida Endlicher, Loniceropsida Brongniart

ADOXACEAE Trautvetter, nom. cons.   Back to Dipsacales

0-methylated flavonols only +; true tracheids?; pericyclic sheath poorly developed; (nodes 1:1, 5:5); (stomata paracytic); (petiole also with adaxial inverted bundles; closed C-shaped and with wing bundles); glandular hairs common; (bud scales 0); leaves involute or conduplicate (plicate), 2ndary veins palmate to pinnate, (stipules on leaf base); (flowers 4-merous); K open, usu. very small, with one trace, C rotate, G not entirely inferior, lateral and dorsal carpellary bundles free, ventral bundles move from axis to ovary septae, 1 median crassinucellate ovule/carpel, endothelium +, style short, stigma lobed, dry or wet; fruit drupaceous; seed often ruminate, exotestal cells palisade or not; (embryo large); n = (8-)9.

5[list]/200. North temperate, tropical montane, but not in Africa (Map: from Hultén 1958, 1971; Meusel et al. 1992). 2 groups below. [Photos - Collection]

1. Viburnum

Shrubs (trees); hairs stellate and variants; G [3], odd member abaxial, 2 abort, nectary on top of G.

1/175. North temperate, tropical montane, but not in Africa. [Photo - Flower]

For a phylogeny of Viburnum, see Winkworth and Donoghue (2005), for variation in its endocarp and seed, see Jacobs et al. (2008).

Synonymy: Tinaceae Martynov, Viburnaceae Rafinesque

2. Adoxa, etc.

Shrubs or herbs; (cambium storied - Sambucus); vessel elements with simple perforations; leaves compound (deeply lobed); A extrorse (8, monothecal), G 1, [5], opposite C, embryo sac tetrasporic, but eight nucleate [Adoxa-type], nectary on top of G or on C associated with multicellular hairs, styles +, separate, stigmas capitate.

4/23. Mainly north temperate, esp. China, also (sub)tropical montane.

Sambucus has crystal sand. Adoxa is distinctive in lacking any obvious corolline ring primordium and in its eight stamens with monothecate anthers, amoeboid tapetum, nectary on the petal lobes, tenuinucellate ovules, weak endothelium, etc. (Erbar 1994). The leaves at the bases of the rosettes and on the rhizomes are spiral and there are no extrafloral nectaries (cf. Sambucus) In Sinadoxa the stamens appear to be divided into two half stamens, each with a separate filament and a monothecal anther; it is molecularly close to Adoxa (Liu et al. 2000). Donoghue et al. (2003) describe the flowers of Sinadoxa as having three corolla lobes and a single carpel. In the curious genus Tetradoxa the half anthers are peltate, there are separate styles, the ovary was described as being superior, and the sepals are persistent (Ying et al. 1993). Adoxa itself has five carpels with five styles (Leins 2000).

For more details of the synapomorphies of this clade, and of clades within it, see Donoghue et al. (2001b, 2003).

Synonymy: Sambucaceae Borkhausen

• Adoxaceae may be recognised by their opposite, toothed leaves that are compound or simple. The inflorescence is usually flat-topped, cymose, and has numerous small flowers. The flowers are 5- or sometimes 4-merous, the calyx is open during development, the corolla is rotate, the style is at most short, and the fruit is drupaceous. Some Cornaceae look rather similar to Viburnum, but the former often have 4-merous flowers, they lack stellate indumentum, and their lateral veins ascend towards the apex of the blade.

Early divergence within this clade can be dated to ca 91-75 million years before present (Bell & Donoghue 2005a).

Tannin-secreting tubes in Sambucus are coenocytic and up to 32.8 cm long, i.e., the length of an internode (Zobel 1986). A fibrous pericyclic sheath in Viburnum may be absent, and that of Sambucus interrupted; that of Caprifoliaceae s.l. is better developed. The cells in the latter are also longer, except those of Linnaea (Cooper 1939). There is the same number of stamens as petals (cf. many Dipsacaceae s.l.). The chromosomes are distinctive. They are large (cf. Caprifoliaceae, etc.), continuously condensed from prophase to metaphase, the proximal regions normally condensing first, but when cold, areas of the mitotic chromosomes are not condensed (Benko-Iseppson & Morawetz 2000).

Downie and Palmer (1992) associate Adoxaceae with Asterales, while they are sister to Apiales in some analyses (Backlund and Bremer 1997).

Synonymy: Sambucaceae Borkhausen, Tinaceae Martynov, Viburnaceae Rafinesque

Diervillaceae [Caprifoliaceae [Linnaeaceae [Morinaceae [Valerianaceae + Dipsacaceae]]]] [= Caprifoliaceae s.l.]: bark papery-flaky; O-methylated flavones, flavonols +; cork deep-seated; wood often fluorescing; (pith diaphragms +); pericyclic fibers moderately developed; flowers rather weakly monosymmetric [not the K], medium-sized, C 2 + 3, nectary on C associated with unicellular hairs, anthers sagittate, tapetum plasmodial, pollen grains spheroid, echinate, lateral and dorsal carpellary bundles 0, ventral bundles in axis, stigma capitate, wet; (testa hypodermis also differentiated, fibrous or not); chromosomes "small"; duplication of dipsCYC2 and dipsCYC3 genes, horizontal transfer of mitochondrial rps11 gene [?Morinaceae and upwards in the tree].

Early divergence within this clade can be dated to ca 81-60 million years before present (Bell & Donoghue 2005a).

The glandular leaf teeth have a main vein plus two accessory veins, or one accessory vein proceeding above the tooth. Transpetal veins, branch veins linking adjacent median veins, occur in the upper part of the corolla in at least Diervilla, Kolkwitzia and some Valerianaceae and Dipsacaceae (Gustafsson 1995). The calyx often persists, characteristically remaining small and perched on top of the fruit, which may be narrowed towards the apex. Biparental plastid transmission occurs in some taxa, but sampling is poor.

The circumscription, etc., of families follows Backlund and Bremer (1997) and Backlund and Pyck (1998). Note that the small families recently recognised in Dipsacales are a consequence of maintaining the well known Dipsacaceae and Valerianaceae in their old circumscriptions - the small clades resulting from the break-up of the old, broadly-circumscribed Caprifoliaceae remained unaccounted for. The whole lot might usefully be combined in a Caprifoliaceae s.l. (see also A.P.G. 2003), since similarities between the families are considerable and differences are mostly slight.

Some information is taken from Magócsy-Dietz (1899: pith diaphragms, woody members only) Carlquist (1982: wood anatomy), Wagenitz and Laing (1984: nectaries), Verlaque (1988: relationships), Ogata (1988, 1991: wood anatomy), Hoffmann and Göttmann (1990: general), Backlund and Donoghue (1996: general), Backlund and Nilsson (1997: pollen), Backlund and Pyck (1998: general), Benko-Iseppson and Morawetz (2000: general), Nilova (2001: bark anatomy) and Donoghue et al. (2001b) and especially Bell et al. (2001: both general).

DIERVILLACEAE Pyck   Back to Dipsacales

Shrubs; leaves involute [Weigela]; nectary at base of C, filaments hairy, pollen pororate, membrane granulose, G [2], many ?marginal ovules/carpel; fruit beaked, septicidal down sides; n = 9.

1-2/16. East Asia, S.E. U.S.A. (Map: from Li 1952, approximate).[Photo - Flowers © M. Clayton]

The large nectary at the base of the corolla in Diervilla (perhaps including Weigela) is a swelling covered by nectar-secreting hairs similar to those in Lonicera, etc. Only one carpel may be fertile, and in some species there may be an "epicalyx" (see below) immediately below the ovary.

Caprifoliaceae [Linnaeaceae [Morinaceae [Valerianaceae + Dipsacaceae]]]: fruit indehiscent.

Note that taxa with connate leaf bases, especially of inflorescence bracts, are scattered through this clade.

CAPRIFOLIACEAE Jussieu, nom. cons.   Back to Dipsacales

Shrubs (trees); vessel elements usu. with simple perforations; leaves supervolute or conduplicate (involute - Heptacodium), margins entire, 2ndary veins pinnate to palmate; K small, A (4-)5, filaments glabrous, G [3(-4)], all, 3/4 or 2/4 fertile, odd member adaxial (opposite C - Leycesteria), 1-8 ovules/carpel; fruit baccate [Lonicera] or drupaceous [Symphoricarpus]; n = 9; deletion in the chloroplast gene clpP.

5[list]/220: Lonicera (180). Mostly N. temperate, esp. East Asia and E. North America (Map: see Hultén 1971; Hultén & Fries 1986; Meusel et al. 1992). [Photo - Flower]

There is no stem endodermis. Heptacodium has cork forming in the middle of the cortex and well-developed cortical fibers. Caprifoliaceae also include Triosteum and Symphoricarpus. Triosteum seems to lack dorsal carpellary bundles only and has apotropous ovules (Wilkinson 1949), while the drupes in Symphoricarpus have a thick layer of narrow, vertical fibers on the outside, then a layer of horizontal fibers, and the seed coat itself is crushed.

Synonymy: Loniceraceae Vest

Linnaeaceae + Morinaceae + Dipsacaceae + Valerianaceae: supernumerary bracts from aborted flowers +; A 4, didynamous, G [3], 2 abort; fruit a cypsela.

For various interpretations of the supernumerary bracts, bracteoles, epicalyx, and involucel in these families, see Weberling (1992), Roels and Smets (1996), Donoghue et al. (2003, and literature cited) and Pyck and Smets (2004). The epicalyx is described as consisting of four fused bracts and having nothing to do with the bracteoles (Hofmann & Göttmann 1990; Mayer 1998); the individual flowers may be the terminal flower of a partial thyrsoid inflorescence (esp. Roels & Smets 1996). In the characterisations below, the particular derived condition for each family is described; what synapomorphies might be is unclear (Bell et al. 2001). In general, where there are only two stamens, the adaxial pair persists. Of the three carpels, it is the adaxial lateral carpel that remains fertile (Donoghue et al. 2003).

LINNAEACEAE Backlund   Back to Dipsacales

Shrubs (± herbaceous); vessel elements usu. with simple perforations; leaves supervolute(-curved); nectariferous petal abaxial, filaments hairy, G [(4)], ovule ?apotropous; K and/or bracts often modified in fruit; n = 8, 9.

4-5/36. Temperate South East Asia (N. Temperate, inc. Mexico). Linnaea, Dipelta (subfleshy, 2-seeded fruits), Kolkwitzia, Zabelia, Abelia. [Photo - Habit] [Photo - Flower]

For distinctive Eocene fruits assignable to this group and their implications for biogeography and evolution, see Manchester and Donoghue (1995).

Morinaceae + Dipsacaceae + Valerianaceae: perennial rosette herbs with taproot; monoterpenoids, cathecolic tannins, alkaloids +, ellagic acid 0; libriform fibers +; flank-bridge in stem between lateral bundles; bud scales 0; filaments glabrous, anthers dorsifixed, nectary at base of C, G with sterile loculi much reduced, 1 apical ovule/flower, prominent endothelium with crystal layer, chalazal nuclei variously proliferating; exotesta not thickened; endosperm scanty, embryo large; distinctive expansion of the chloroplast inverted repeat.

For flank-bridges, see Neubauer (1979); it is as if two bundles on each side form split laterals, and one branch from each bundle fuses in the middle, so forming the bridging bundle. Bundles innervating the petiole arise from the bridging bundle, except in Morina.

For a comparison of the three families, see Cannon and Cannon (1984), for embryology, see Johri et al. (1991), and for relationships suggested by some morphological characters, see Peng et al. (1995).

MORINACEAE Rafinesque   Back to Dipsacales

Ethereal oils +, iridoids 0; nodes 5:5; stems hollow; leaves involute, margins spinose to pinnatifid (entire), 2ndary veins palmate, bases sheathing; inflorescence of sessile cymes [verticels], epicalyx 12-ribbed; flowers strongly monosymmetric, K 4, monosymmetric, A pairs inserted at different heights on the C tube (2, + 2 staminodes), extra thickened layer of pollen wall, tapetum ?glandular, pollen binucleate, (turret-like triporate), exine columellae reduced, hypostase +, chalazal cells producing multicellular structures; integument multiplicative, not vascularised, outer layer only persisting; endosperm ruminate; n = 17, chromosomes 0.7-1.5 µm long; duplication of dipsCYC2 and dipsCYC3 genes.

2-3[list]/13. Balkans to China (Map: see Cannon & Cannon 1984). [Photo - Morina Inflorescence, Acanthocalyx Inflorescence.]

• Morinaceae are robust, perennial herbs. They may be recognised by their opposite leaves with connate bases and often spiny margins and inflorescences consisting of whorls of flowers, each flower having a 12-ribbed epicalyx. The flowers are sympetalous and strongly monosymmetric.

The calyx is distinctly monosymmetric. Remarkable intine-covered structures like pollen tubes are produced in all taxa before pollen germination (Blackmore & Cannon 1983). The integument is 14-18 cells across when the embryo sac is mature, becoming ca 25 cells across later (Vijayaraghavan & Sarveshwari 1968).

For tables of differences between Morinaceae and Dipsacaceae, see Vijayaraghavan and Sarveshwari (1968), Cronquist (1981), Cannon and Cannon (1984) and Johri et al. (1992). There seems to be total confusion as to the nature of the tapetum of Morina: Vijayaraghavan and Sarveshwari (1968) describe it as being polyploid, multinuclear and secretory, Kamelina (1983) as cellular, binuclear and glandular, and Johri et al. (1992) as being plasmodial (and that of Dipsacaceae as being glandular).

For embryology, see also Vijayaraghavan and Sarveshwari (1968: Morina longifolia only), for a monograph of the family, see Cannon and Cannon (1984), and for its phylogeny and biogeography, see Bell and Donoghue (2003).

Dipsacaceae + Valerianaceae: (annual herbs); saccharose +, quercetin 0; vessel elements with simple (scalariform) perforations; (nodes 5 or more:5 or more); leaves simple to ± pinnate, conduplicate (margins entire); flowers rather small; A ± equal in length, tapetal cells 4 or more nucleate [?level], exine columellae prominent and branched, chalazal cells 2-4-nucleate, stigma dry; embryo green.

DIPSACACEAE Jussieu, nom. cons.   Back to Dipsacales

(Shrubby); starch almost 0; (stomata anisocytic); inflorescence capitate, epicalyx 8-ribbed; lateral abaxial C lobes overlapping adaxial lobes, (C with 4 lobes), (A 2-3), (pollen 3-porate), micropyle very long, hypostase +, G [2, 3] [latter - Triplostegia], micropyle very long, chalazal nuclei polyploid, stigma entire or 2-lobed; fruit with calycine awns or bristles; endosperm + (slight in Triplostegia); n = 5, 7-9(-10), chromosomes 1-5 µm long.

11[list]/290: Scabiosa (80), Cephalaria (65), Knautia (60). Eurasia, Africa, esp. Mediterranean region, to New Guinea (Triplostegia) (Map: see Meusel et al. 1976; Hultén & Fries 1986; also Verlaque 1985). [Photo - Habit, Inflorescence, Flower.]

• Dipsacaceae are herbs with opposite leaves, capitate, involucrate inflorescences and more or less monosymmetric flowers each with a well-developed epicalyx. The dry fruit has a single seed.

The cork of Knautia may be superficial (Metcalfe & Chalk 1950).

Triplostegia, which has a double epicalyx and valepotriates, seems best assigned to Dipsacaceae (e.g. 100% support in a 30 taxon-5 gene analysis - Davis et al. 2001; see also Bell & Donoghue 2000; Zhang et al. 2001; Bell 2004). However, Pyck and Smets (2004) show that although a two-gene analysis places Triplostegia in this position, morphological data alone and when combined with the molecular data place it sister to Valerianaceae. As they note, [Triplostegia + Valerianaceae] have valpotriate-type iridoids, a pollen aperture with a halo, a granulose colpus, and also endosperm reduction in common, and possibly even epicalyx/bracteole similarities. Where Triplostegia is placed will substantially affect apomorphy position.

For embryology, see Kamelina (1983), for fruit, see Verlaque (1977), for a general study, see Verlaque (1985, 1986), for phylogeny and the evolution of seed dispersal syndromes, see Caputo et al. (2004).

Synonymy: Scabiosaceae Adanson, Triplostegiaceae Airy Shaw

VALERIANACEAE Batsch   Back to Dipsacales

Foetid monoterpenoids and sesquiterpenoids, valpotriates +; true tracheids ?; leaf bases often sheathing; (plant dioecious), flowers small, (polysymmetric), bracteoles +, epicalyx 0; K small, abaxial C spurred (or not), A 1-4 (5), pollen colpate, (G with sterile loculi well developed); K + (a pappus; reduced); testa 1-layered; n = (7-)8(9-12), chromosomes 0.7-4 µm long.

17[list]/315: Valeriana (200: perhaps para- or polyphyletic - Hidalgo et al. 2004), Valerianella (80). N. temperate, especially Mediterranean, and Andean South America (half the family) (Map: from Hultén 1958; Meusel et al. 1978). [Photo - Habit, Flower, Flower.]

• Valerianaceae are often foetid herbs with opposite, sometimes connate leaves and rather small flowers. The inflorescence is cymose and bracteolate. The sympetalous corolla is often spurred but other than that may be only weakly monosymmetric; the calyx often develops greatly in fruit.

Crown-group Valerianaceae may be 60-55 million years old (Bell & Donoghue 2005a), but diversification in the Andean paramo - ca 1/7 of the family - happened less than 5 million years ago (Bell & Donoghue 2005b).

Patrinia may be sister to the rest of the family (Pyck 2002), Nardostachys sister to the remaining taxa (Bell 2004; Bell & Donoghue 2005b: both with very strong support), or the two together form a well-supported clade sister to other Valerianaceae (Hidalgo et al. 2004); the former topology is more likely. Valeriana celtica, Valerianella and Centranthus may be successively sister to Valeriana (Bell & Donoghue 2005b, for which see for further details).

Valpotriates are triesters of route I secoiridoids. The calyx in Patrinia and in particular Nardostachys is well-developed. Evident sterile loculi, a well developed calyx, an androecium with either four or five stamens, etc., are likely to be plesiomorphic in the family. The corolla tube of Centranthus is divided vertically into two by a septum. The extra "bracteole" of Patrinia may be an interpolated structure that develops into a fruit wing (Hoffmann & Göttmann 1990).

For valepotriate distribution, see Backlund and Moritz (1998), for a phylogeny of the family, see Bell (2004) and Hidalgo et al. (2004).