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 II / CAMPANULIDAE: myricetin 0; vessel elements with scalariform perforation plates; style short; flowers rather small, style short; endosperm copious, embryo short/very short.

[ASTERALES [ESCALLONIALES [BRUNIALES [APIALES [PARACRYPHIALES + DIPSACALES]]]]] / APIIDAE: iridoids +; C tube initiation early; G [2-3], inferior.   Back to Main Tree

]ESCALLONIALES [BRUNIALES [APIALES [PARACRYPHIALES + DIPSACALES]]]]: ?

[BRUNIALES [APIALES [PARACRYPHIALES + DIPSACALES]]]: ?

[APIALES [PARACRYPHIALES + DIPSACALES]] / DIPSAPIIDAE: ?

Previous Relationships. Various families have been placed here or elsewhere in the asterid II clade, but with uncertain support; recent work is clarifying their relationships (Winkworth et al. 2008a; Tank & Donoghue 2010). For Polyosmaceae and Escalloniaceae, see below; Paracryphiaceae, Quintiniaceae, and Sphenostemonaceae are combined as Paracryphiaceae and form a clade sister to Dipsacales; while Columelliaceae and Desfontainiaceae (as Columelliaceae) are close Bruniaceae, together making up Bruniales.

APIALES Nakai  Main Tree, Synapomorphies.

Woody; route II decarboxylated iridoids +; vessels solitary; pits [both vessels and fibres] bordered; ?stomata; lamina pinnatinerved (margins toothed or lobed); inflorescence terminal, paniculate; plants dioecious; pedicels articulated; flowers small, K small, C apparently free; A free from C; G [3], abaxial carpel fertile [?Pennantia], placentation apical; ovules 1-2/carpel, apotropous, nucellus type?, funicular obturator +; fruit a single-seeded drupe; endosperm nuclear; x = 6?; mitochondrial rpl2 gene lost. - 7 families, 494 genera, 5489 species.

Evolution. Divergence & Distribution. Apiales contain ca 2.4% eudicot diversity (Magallón et al. 1999). Wikström et al. (2001) suggest a Santonian-Turonian age for the clade of some 90-85 million years before present, with divergence in the Apiaceae-Araliaceae area occurring 48-46 million years before present, although details of relationships within the clade differ from those given here. Janssens et al. (2009) date stem group Apiales to 104±11.2 million years ago and the crown group to 87±14.1 million years, while Magallón and Castillo (2009) offer estimates of ca 92.8 and 93.1 million years for relaxed and constrained penalized likelihood datings respectively for the stem group, the crown group dating to ca 74.8 and 75 million years (relaxed and constrained estimates again) - but note topology, Paracryphiales are way basal.

Other. Thinking about morphological evolution is particularly difficult here, and is complicated both by incomplete knowledge and extensive variation in the characters of interest. The basal pectinations are genera which used to be in Cornales/Cornanae - and they have transseptal bundles in common, as well as clustered vessels, septate fibres with simple pits, some rays over 10 cells wide and with square or upright cells (Noshiro & Baas 1998; Baas et al. 2000). The even more different Pennantia, late of Icacinaceae, may also be placed here. Unfortunately, corolla initiation, pollen nucleus number, and many other characters are unknown for these taxa, although some information for the ex-Cornalean genera can be found in Patel (1973), Philipson (1967), and Philipson and Stone (1980). Griseliniaceae and Torricelliaceae both have griselinoside, transseptal bundles in the ovary, and the abaxial carpel alone is fertile, the single ovule being apotropous. Pennantia, perhaps sister to all other Apiales, has a superior ovary (and sometimes a thick, disciform, sessile stigma). In particular, how the gynoecium of Pennantia is interpreted (summarized in Kårehed 2003a) has many implications for character evolution - and if it does not belong in this clade at all...! Here the gynoecium is interpreted as being tricarpellate, although it appears to be only a single carpel, and it is assumed that the abaxial carpel is fertile (see also Chandler & Plunkett 2004; Plunkett et al. 2004c for carpel number).

Further complicating the issue, the sister group to the [Apiales [Paracryphiales + Dipsacales]] clade is Bruniales, a small but morphologically very heterogeneous clade, and so character evolution in the basal part of Apiales in particular is very uncertain. Thus of taxa close to Apiales, Sphenostemon (Paracryphiaceae, Paracryphiales), has a superior ovary, in Adoxaceae, sister to other Dipsacales, the ovary is only semi-inferior (and in Tetradoxa the ovary was described as being superior - Ying et al. 1993), and in Bruniales the ovary varies from superior to inferior. Understanding perforation plate variation in a phylogenetic context is similarly problematic.

Yi et al. (2004) suggest that the basic chromosome number in Apiales is x = 6 (see also Raven 1975), although the order then would have all polyploid/dysploid members, with several independent origins of polyploidy.

Chemistry, Morphology, etc. Kårehed (2003, for which see for further details, also Chandler & Plunkett 2004) provides a good summary of what is known of the main clades in Apiales. For wood anatomy, see Lens et al. (2008a). Endress (2003c) summarizes the literature on nucellus development in the clade; there are a number of glaring gaps in our knowledge. For nectary morphology, see Erbar and Leins (2010).

Phylogeny. Within Apiales, the grouping (Griselinia (Aralidium + Torricellia)) is rather weakly supported, mainly in earlier studies (Backlund & Bremer 1997; see also Chandler & Plunkett 2002). The ex-Icacinaceae Pennantia is sister to other Apiales (Kårehed 2003; Lens et al. 2008a). Plunkett (2001) and Lundberg (2001c) both suggest that Torricelliaceae and Griseliniaceae are successive clades near the base of Apiales, and this has strong Bayesian support (Kårehed 2002a: four genes, all genera sampled), and this topology is followed here (see also Soltis et al. 2011); note that the relationship is reversed in, but with a p.p. of 0.93. Chandler and Plunkett (2004) and especially Tank and Donoghue (2010) are resolving relationships both within Apiales and between Apiales and their immediate relatives (see also tree). Some Bayesian analyses yield strong posterior probabilities for a relationship between Myodocarpaceae and Pittosporaceae (Chandler & Plunkett 2004), but on balance the relationships [Pittosporaceae [Araliaceae [Myodocarpaceae + Apiaceae]]] seem most likely (Tank et al. 2007; Tank & Donoghue 2010; Soltis et al. 2011).

Previous Relationships. Apiales include Pennantia, late of Icacinaceae. Of other taxa placed here, Melanophylla was included in Hydrangeales and Torricellia, Griselinia and Aralidium in separate monogeneric orders, all in Cornidae-Cornanae, by Takhtajan (1997); all have been placed in Cornaceae s.l.

There are some similarities between [Pittosporaceae [Araliaceae [Myodocarpaceae + Apiaceae]]] and some Asterales (esp. Campanulaceae s.l. and Asteraceae) (e.g. Erbar & Leins 2004; Leins & Erbar 2004b), thus 1-benzyltetrahydroisoquinoline alkaloids are found in both (Kubitzki et al. 2011). However, given the rather strongly supported set of relationships at the base of Apiales, the other clades that are in this part of the asterid II phylogeny, and relationships within Asterales (Campanulaceae s.l. and Asteraceae are not immediately related), most of these similarities will probably be plesiomorphies or more likely parallelisms (see also below).

Includes Apiaceae, Araliaceae, Griseliniaceae, Myodocarpaceae, Pennantiaceae, Pittosporaceae, Torricelliaceae.

Synonymy: Apiineae Plunkett & Lowry, Aralidiinae Thorne & Reveal - Ammiales Small, Araliales Berchtold & J. Presl, Aralidiales Reveal, Griseliniales Reveal & Doweld, Hederales Link, Pennantiales Doweld, Pittosporales Link, Torricelliales Reveal & Doweld

PENNANTIACEAE J. Agardh   Back to Apiales

Trees or shrubs; iridoids ?; diffuse apotracheal parenchyma +/0; nodes 3:3; petiole bundle annular (with a medullary bundle) and with solid wing bundles; stomata paracytic; hairs uniseriate; lamina margins also entire; K free, C connate, valvate, apex inflexed; nectary 0; staminate flowers: A dorsifixed (epipetalous), filaments long; pistillode +; carpellate flowers: staminodes +/0; G [3], also [2], styles short, stigmas punctate, or stigma sessile, broad; ovules at most thinly crassinucellate, integument vascularized; drupe with inner cells transversely elongated; seed coat thin; endosperm development?, embryo short/minute [to 1/3 the seed length]; n = 25.

1/4. N.E. Australia, Norfolk Island, New Zealand (map: from van Balgooy 1966; George 1984). [Photo - Habit.]

Chemistry, Morphology, etc. Collenchyma is only poorly developed, and a pericyclic sheath is present; pits in general are bordered. For the morphology of the stigma, see Kårehed (2002b). For information, which should be confirmed, on ovule morphology, see Mauritzon (1936c).

For other information, both about Pennantiaceae and about other members of the old Icacinaceae (here in Garryales and Aquifoliales), see Miers (1852: ovule orientation), Bailey and Howard (1941: anatomy); see also Fagerlind (1945: embryology), Heintzelmann and Howard (1948), Padmanabhan (1961: embryology), Sleumer (1971a: general), van Staveren and Baas (1973: epidermis), Baas (1973: epidermis, 1974: stomata), Lobreau-Callen (1980: pollen), Kaplan et al. (1991: chemistry), Teo and Haron (1999: anatomy), Kårehed (2001, 2002b, 2003: the taxa in their current circumscription), and Lens et al. (2008a: wood anatomy).

Classification. Gardner and de Lange (2002) monographed Pennantia, providing a number of interesting morphological and anatomical details.

[Torricelliaceae [Griseliniaceae [Pittosporaceae [Araliaceae [Myodocarpaceae + Apiaceae]]]]]: polyacteylenes +; young stems with peripheral collechyma; vessels mainly in groups; vessel element perforations simple; pits in general with at most narrow borders; paratracheal parenchyma +, scanty; pericyclic fibres 0 or few; nodes 5(+):5(+); leaf bases broad; C apparently free, imbricate; G inferior, styles/stigmas recurved; nectary on top of ovary.

Chemistry, Morphology, etc. Polyacetylenes, mainly aliphatic, including the C₁₇ acetylenes, falcarinone, etc., are found in the [Pittosporaceae [Araliaceae [Myodocarpaceae + Apiaceae]]] clade, while the polyacteylenes of Torricellia angulata, quite recently described, are C₁₁ acids that are unique in having a chiral center (Pan et al. 2006); iridoids are found in the same species (Liang et al. 2009).

For the wood anatomy of this clade, see Lens et al. (2008a).

TORRICELLIACEAE H. H. Hu   Back to Apiales

Trees; griselinoside, ellagic acid +, tanniniferous [Torricellia]; (vessel elements with scalariform perforation plates - Aralidium); petiole bundles scattered [Aralidium]; crystal sand +; mucilage cells +; stomata anomocytic (anisocytic); glandular hairs +; lamina margins lobed and toothed or toothed, (2ndary veins ± palmate), petiole margin with basal flange, (small ligule +), encircling stem or not; K medium, imbricate or largely connate, staminate flowers: (C induplicate-valvate - Torricellia); pollen tectum reticulate; carpellate flowers: (C 0 - Torricellia); G [(2-4)], (nectary vascularized - Aralidium), transseptal bundles +, (stigmas ± bifid - Torricellia); ovules with massive integument [Aralidium]; fruit with two large empty loculi and one smaller fertile loculus [?Melanophylla], endocarp with sclereids; seed ± curved, (ruminate, coat vascularized [Aralidium]), exotesta scalariform-thickened, unlignified [Melanophylla], testa slightly sclerified [Torricellia]; (embryo long, thin - Torricellia); n = 12, 20 ± 2.

3[list]/10. Madagascar, South East Asia and W. Malesia (map: fossils [blue] from Meller 2006). [Photo: Melanophylla Habit, Flower.]

Evolution. Divergence & Distribution. For the fossil history of the East Asian endemic Torricellia, see Meller (2006) and Manchester et al. (2009); the genus was widespread in the northern hemisphere in the Eocene.

Chemistry, Morphology, etc. For fruit and seed of Melanophylla, see Trifonova (1998). Other information is taken from from Philipson (1977), Lobreau-Callen (1977: pollen), Philipson and Stone (1980), and Takhtajan (2000).

Phylogeny. For the circumscription of this clade, see also Plunkett et al. (2004); relationships are [Aralidium [Melanophylla + Torricellia]] (see also Soltis et al. 2011).Classification. For a revision of Melanophylla, see Schatz et al. (1998).

Synonymy: Aralidiaceae Philipson & B. C. Stone, Melanophyllaceae Airy Shaw

[Griseliniaceae [Pittosporaceae [Araliaceae [Myodocarpaceae + Apiaceae]]]]: petroselenic acid + [in seed: CH₃-[CH₂]₁₀-CH=CH-[CH₂]₄-COOH]; hairs rarely glandular; petals 1-veined; ovule with endothelium.

GRISELINIACEAE A. Cunningham   Back to Apiales

Trees or shrubs (climbing, epiphytic); griselinoside +, polyacteylenes?, tannins 0; vessels single, vessel element perforations scalariform; pits in general with distinct borders; axial parenchyma diffuse-in-aggregates, scanty; petiole bundles (incurved) arcuate; mucilage cells +; stomata cyclocytic; hairs unicellular; leaves two-ranked, lamina conduplicate, margins toothed or entire, bases with petiole margin + adaxial flange, encircling stem, or not; K open; staminate flowers: A dorsifixed; pollen tectum striate; carpellate flowers: (C 0); nectary 0; G [(4)], transseptal bundles +, (2 carpels fertile); ovule crassinucellate [weakly so], funicular obturator +; fruit baccate; testa ?many layered, outer two (and esp, third) layers with thickened walls; embryo long; n = 18.

1[list]/6. New Zealand and S. South America (map: from Dillon & Muñoz-Schick 1993). [Photo: Inflorescence, Leaves, Habit, Flower (scroll to end).]

Chemistry, Morphology, etc. For seed fatty acids, see Badami and Patil (1981), in part. The wood has solitary vessels and apotracheal parenchyma (Baas et al. 2000). Takhtajan (2000) provides details of embryo and testa. For leaf insertion, cf. Philipson (1967), and for leaf base, cf. Takhtajan (1997). For Griselinia flowers, see Eyde (1964), for ovule, see Warming (1913). Further information is taken from Philipson (1977) and Dillon and Muñoz-Schick (1993).

Previous Relationships. Eyde (1964) suggested a relationship between Griselinia and Garrya (Garryales) and Cornaceae (Cornales).

[Pittosporaceae [Araliaceae [Myodocarpaceae + Apiaceae]]]: plant often aromatic, ethereal oils, acetate-derived anthroquinones, coumarins +, iridoids, flavonols, tannins 0; lateral roots originating from either side of the xylem poles; schizogenous secretory canals in pericycle, phloem, etc.; parenchyma in secondary phloem surrounding the secretory canals and in groups with sieve tubes; (nodes 3:3); petiole bundles arcuate or annular; leaves conduplicate; flowers perfect and imperfect, plant andromonoecious; C tube formation early; pollen trinucleate; G [2], both fertile, stigma wet; hemicellulosic seed reserves common [?right place]; x = 12.

Evolution. Plant-Animal Interactions. Which groups are food plants for butterfly larvae may be of interest. Ehrlich and Raven (1964) note that some butterflies that do not seem to like Araliaceae, including Hydrocotyle, are found on Apiaceae (?including Saniculoideae); thus the Papilio machaon group is not found on Araliaceae because that family lacks the furanocoumarins that the caterpillars like (Berenbaum 1983).

Other. It is likely that many of the apparently plesiomorphous characters of Pittosporaceae, e.g. superior ovary with several ovules, etc., are derived. Indeed, the general floral morphology of Pittosporaceae is quite probably derived, rather than representing the plesiomorphic condition from which the distinctive flowers of [Apiaceae + Araliaceae] evolved. (Note that the leaves of seedlings of Pittosporum may be pinnatifid.)

Chemistry, Morphology, etc. Triterpenoid ethereal oils produce the distinctive odour characteristic of many of these plants; see Jay (1969) for suggestions based on plant chemistry that members of this group are related. Lateral roots originate from either side of the xylem poles because a resin canal runs down the stem at the apex of the pole (Van Tieghem & Douliot 1888).

Note that there are a number of characters that may be of systematic interest and delimit clades of various sizes here. These include the presence of sesquiterpene lactones and benzylisoquinoline alkaloids; inverted vascular bundles in the pith and/or cortex; presence of crystal sand; exotestal cells tangentially elongated, tanniniferous. As to other characters, the vessel:ray pits are bordered (Baas et al. 2000). Members of both Araliaceae s. str. and Apiaceae s. str. in clades that are sister to the rest of these families have simple leaves, as have Myodocarpaceae (Plunkett 2001) and of course Pittosporaceae, so compound leaves may have evolved independently in Apiaceae and Araliaceae. Leaf teeth have a broad glandular apex with a main and two accessory veins, or one vein proceeds above the tooth; a survey of tooth morphology might be interesting.

For information on ventral carpel bundles, see Philipson (1970) and Eyde and Tseng (1971); when the united ventral bundles are opposite the carpels, the two bundles come from the same carpel, and when they are in the septal radii, the two bundles are derived from adjacent carpels. For ovule morphology, see Jurica (1922) and van Tieghem (1898). According to the latter, Apiaceae have a thick integument (e.g. ca 7 cells - Gupta 1970), that of Hedera is very thick, although Philipson (1977) described the integument of Araliaceae as being "thin". A synthesis of what is known about ovule number and type would be useful (but see Philipson 1970 for ovule number). Note that there is not only variation in what kinds of calcium oxalate crystals are found in the fruit wall, i.e., single rhomboidal crystals or druses, but also where they occur, e.g. in the endocarp or mesocarp, all around the fruit or only in commissural area (Liu et al. 2006); I have only just begun to work out the phylogenetic significance of the later variation (see also Rompel 1895; Burtt 1991a). Kleiman and Spencer (1982) surveyed Apiaceae and Araliaceae for the occurrence of petroselenic acid.

Some Pittosporaceae and a few Araliaceae have basally connate petals (Plunkett 2001). Erbar and Leins (1988a, 1996a, 2004) suggested that the nectary "disc" of Apiaceae and Araliaceae is a carpellary flank nectary displaced by intercalary growth, and that the axile placentation of these two families is easily related to the parietal placentation of Pittosporaceae. In Pittosporaceae there was a short basal zone with separate loculi, the ovules being borne above this zone - essentially the same position in which the ovules of Apiaceae and Araliaceae are found. However, gynoecial development, etc., in the whole Apiales needs reinvestigation, given the inclusion of the superior-ovaried Pennantiaceae as sister to the rest of the order - and taxa with more or less superior ovaries are scattered throughout the asterid II clade (see Ronse Decraene & Smets 2000 for the possible connection between early corolla tube formation and an inferior ovary).

For similarities in woody anatomy between Apiaceae and Araliaceae, see Metcalfe and Chalk (1983); for variation in the sequence of initiation of parts of the flower, see Erbar and Leins (1985: mostly Apiaceae, also Hydrocotyle, the latter rather different); for chromosome numbers, see Yi et al. (2004); for fruit wings and fruit anatomy, see Liu et al. (2006); for nectaries, see Erbar and Leins (2010), and for bark anatomy, see Kotina et al. (2011: lots of information on crystal types and their distributions, but not yet integrated into the phylogeny).

Phylogeny. Pittosporaceae may be sister taxon of the whole group (e.g. Kårehed 2002c; Andersson et al. 2006, strong support, but Myodocarpaceae not included), and this position was found to be strongly supported by Tank and Donoghue (pers. comm., D. Tank), however, some studies have found Pittosporaceae to be embedded in the group (see also Chandler & Plunkett 2004) or provided only weak support for a sister group position (Nicolas & Plunkett 2009). In any case, many of the apparently plesiomorphous characters of Pittosporaceae may be derived (see above).

Finally, there is the issue of the demise of the old woody Araliaceae/herbaceous Apiaceae distinction. Myodocarpaceae and Apiaceae-Mackinlayoideae as recognised here both include genera that used to be in Araliaceae, but the precise relationships of the former in particular have been uncertain - see Plunkett and Lowry (2001), Lowry et al. (2001), Plunkett (2001) and Chandler and Plunkett (2004) for more information. Since there are a number of morphological similarities between the Mackinlaya clade and Apiaceae s. str. (Chandler & Plunkett 2002, 2004), the former is included in the latter. Hydrocotyloideae (herbaceous and with simple leaves) were previously included in Apiaceae, but they are highly polyphyletic - Hydrocotyle is here placed in Araliaceae (and this position makes morphological sense), Arctopus is in Apiaceae-Saniculoideae, Azorella and a group of genera form a well supported clade, while Centella, Micropleura, Actinotus, etc., are in Apiaceae-Mackinlayoideae (e.g. Downie et al. 1998, Downie et al. 2000; Chandler & Plunkett 2003, 2004; Plunkett et al. 2004; Andersson et al. 2006; esp. Nicolas & Plunkett 2009). That being said, nodes along the backbone of this part of the tree have rather moderate support (Nicolas & Plunkett 2009). Very few genera remain to be sequenced, and although sampling must be improved in large genera like Hydrocotyle and Trachymene, it is unlikely to affect their positioning in Araliaceae.

For other work on phylogenetic relationships in the Apiaceae-Araliaceae area, see e.g. Judd et al. (1994: Pittosporaceae not included), Oskolski et al. (1997), Oskolski & Lowry (2000), Plunkett (1998), Plunkett et al. (1996, 1997a, 1997b), and Kårehed (2002c).

PITTOSPORACEAE R. Brown, nom. cons.   Back to Apiales

Trees or twining vines; furanocoumarins +, (hydroxycoumarins), non-hydrolysable tannins +, petroselenic acid 0, C₂₀ and C₂₂ fatty acids abundant; young stem with (± interrupted - Pittosporum) vascular cylinder; nodes 1:3, 3:3; petiole bundles arcuate; stomata paracytic; hairs uniseriate, terminal cells vertically or transversely [T-shaped hair] elongated or glandular; lamina vernation supervolute-curved, margins entire, 2ndary veins pinnate, base narrow to sheathing, stipules 0; flowers medium-sized; K large, free (± connate), C often slightly basally connate, 3-5-veined; anthers ± basifixed, placentoid +; nectary on flank of ovary; G [(2-5)], (placentation parietal), style +, straight, stigma capitate (lobed); ovules many/carpel, (incompletely tenuinucellate; apotropous), endothelium 0, funicular obturator 0?; fruit a loculicidal (+ septicidal) capsule or berry, K deciduous; seeds often with sticky pulp, testa many layered, exotestal cells thickened, unlignified.

6-9[list]/200: Pittosporum (140). Old World, especially Australia, tropical and warm temperate, outside the immediate Australian region, mainly Pittosporum (map: from van Steenis & van Balgooy 1966; Good 1974; Palgrave 2002). [Photo - Flower]

• Pittosporaceae are aromatic woody and sometimes thorny plants with simple, estipulate leaves and rather conspicuous flowers that have sepals, petals and stamens equal in number and a gynoecium often with parietal placentation. The fruits are often capsular and enclose pulpy-resinous seeds; the calyx is deciduous.

Chemistry, Morphology, etc. Glucosinolates are reported from Bursaria spinosa, but this is probably a mistake (Fahey et al. 2001). In Pittosporum, at least, the flowers are often functionally unisexual. There is a tendency, especially evident in taxa like Cheiranthera, for the flowers to be obliquely monosymmetrical; asymmetry is largely because of the position of the stamens and gynoecium. Seedlings of Pittosporum have up to five cotyledons.

For endothelium, see Batygina et al. (1985), for seed oils (undistinguished), Stuhlfauth et al. (1985), for vegetative anatomy, Wilkinson (1992, 1998), and for testa anatomy, see Takhtajan (2000: the ovules may be apotropous).

Phylogeny. Cayzer (references in Chandler et al. 2007) has carried out a number of morphological revisions and phylogenetic analyses of parts of Pittosporaceae; changes in taxon limits that she suggests are largely confirmed by a preliminary molecular study (Chandler et al., in Plunkett et al. 2004c). However, generic limits in the Billardiera-Sollya area are still unclear (Chandler et al. 2007). For relationships between species of Pittosporum found in the Pacific, see Gemmill et al. (2002).

Previous relationships. Pittosporaceae were included in Rosales by Cronquist (1981) and Mabberley (1997). However, evidence has been mounting for over 100 years that they were best associated with Apiaceae/Araliaceae (Hegnauer 1969b for a summary of some literature), and Takhtajan (1997) included them as a separate order in his Aralianae (but along with Byblidales).

[Araliaceae [Myodocarpaceae + Apiaceae]]: polyacetylene C₁₈ tariric seed fatty acid +; leaves (compound), lamina margins toothed or otherwise incised; inflorescences terminal, ultimate units umbels; K open; nectary [stylopodium] divided; ovules two/carpel, epitropous, one much reduced; fruits ± laterally flattened, (winged, wings with mesocarp and endocarp, vascular bundles at the margin of wing); hemicellulosic seed reserves common; 92 bp deletion in rpl16 gene.

Evolution. Floral Biology & Seed Dispersal. For the evolution of andromonoecy in this clade, very rare elsewhere in flowering plants and perhaps connected with dichogamy, successively flowering umbels, and umbels as functional units in pollination, see Schlessman (2011).

Chemistry, Morphology, etc. For wood anatomy, see Oskolski (2001), for wing anatomy, see A. R. Magee et al. (2010a), and for the rpl16 deletion, see Downie et al. (2000a).

ARALIACEAE Jussieu, nom. cons.   Back to Apiales

Hydroxycoumarins +, furanocoumarins 0; (vessel elements with scalariform perforation plates); fibres septate (not); axial parenchyma paratracheal; rays heterocellular; stomata para- or aniso-(anomo-)cytic; hairs often stellate or dendroid; stipules cauline or petiolar, or 1 intrapetiolar, or 0; (plants andromonoecious); C valvate (imbricate - Aralia, Panax, etc.); (A 3); ventral carpel bundles are fused bundles of adjacent placentae (the one placenta - e.g. Harmsiopanax), stigma punctate (dry); ovules crassinucellate to tenuinucellate, (nucellar cap +), integument "thin" [?level], (endothelium +), funicle with short hairs as obturator; fruit drupaceous or dry, mesocarp thick-walled, lignified, (berry), with single rhomboidal crystals in cell layer immediately outside endocarp, endocarp sclerified; (seeds ruminate); exotestal cell walls a little thickened; (n = 9, 11, 18).

43/1450. Largely tropical, few temperate. Two groups below.

1. Hydrocotyloideae Link

± herbaceous; nodes 3:3; lamina orbicular-peltate, margin crenate, stipules cauline; (inflorescences axillary); (K 0 - Hydrocotyle); ovule with "short" funicle; fruit schizocarpic, (undivided carpophore +); n = 6<.

4/175: Hydrocotyle (130), Trachymene (45). Tropical, including montane, also warm temperate.

Synonymy: Hydrocotylaceae Berchtold & J. Presl

2. Aralioideae Eaton

Woody (herbaceous); (palisade mesophyll with arm cells); (prickles + - origin various); (hairs stellate, lepidote); leaves also pinnately to palmately compound; (inflorescences [sub]racemose); (C ± connate to calyptrate); (A many; filaments with two traces); nectary [stylopodium] not divided; G [1-5(-200+)], when 5, opposite petals, when 3, median abaxial; integument ca 10 cells across, (parietal tissue +), hypostase +/0; testa multiplicative, exotestal cells tangentially elongated.

41[list - but see Plunkett et al. 2004a for genera]/1275: Schefflera (1600: wildly polyphyletic), Polyscias (160), Oreopanax (80), Dendropanax (70), Aralia (68), Osmoxylon (50). Largely tropical, few temperate (map: see Meusel et al. 1978; Hultén & Fries 1986; FloraBase 2006). [Photo - Flowers, Fruits.]

Synonymy: Hederaceae Giseke, Botryodendraceae J. Agardh

• Araliaceae may be recognised quite easily. They are often rather stout-stemmed and little-branched shrubs or trees, rarely herbs, with large and prominent scars from the fallen leaves; the plant may smell strongly. The leaves are often variously compound and with broad bases, although these latter rarely more or less encircle the stem; stipules are common and are morphologically diverse, although they are generally borne on the leaf base. Petioles are often long, and/or they vary considerably in length on the one shoot; the leaflets are commonly articulated. The ultimate units of the inflorescence are umbels or heads, the flowers are often rather small, there are often three or more carpels and the petals are valvate; the fruit is drupaceous, sometimes flattened laterally, and the seeds may be ruminate.

Evolution. Genes & Genomes. For shifts in the rate of molecular evolution within Araliaceae that are correlated with changes in habit, see Smith and Donoghue (2008).

Chemistry, Morphology, etc. Hedera may have an interrupted fibrous pericyclic sheath; creeping forms have two-ranked leaves. As to stipules - Fatsia (no stipules) x Hedera (no stipules) = X Fatshedera (stipules) - but note that some species of Hedera have a hollowed leaf base with a stipule-like margin, the whole enclosing the bud.

In general, Araliodeae show considerable floral variation, and this is reflected in their floral vasculature: the calyx may be lacking, with not even a reduced vascular trace suggesting that it was ever there, the petals may have three traces, and although generally free they may be slightly to completely connate, and the stamens sometimes have two traces (Nuraliev et al. 2010, 2011). For the anatomy of flower and fruit of Hydrocotyle and genera previously asssociated with it, see Tseng (1967); Hydrocotyle lacks a calyx, and its integument is ca 5 cells across. Both Aralioideae and Hydrocotyle show early corolla tube initiation (Leins & Erbar 1997; Erbar & Leins 2004). Osmoxylon has basally connate petals. Plerandra (= Schefflera) may have up to 25 or more carpels and to 500 stamens; flowers in Aralioideae may be up to 12-merous or more. When stamens are numerous they may be in a single whorl, thus Tupidanthus calyptratus (=Asian Schefflera) has up to 172 stamens and 132 carpels; the carpels are initiated in a single elongated and sometimes contorted whorl looking rather like a brain cactus (fasciated: Oskolski et al. 2005; Nuraliev et al. 2009; see also Eyde & Tseng 1971). Some species of Plerandra have about as many stamens as carpels, separate members of the calyx cannot be distinguished, and although the symplicate zone of the gynoecium develops first, the carpels are largely synascidiate; there is a large, flat remnant of the floral axis within the carpel whorl (Sokoloff et al. 2007b). In other species there are up to five series of stamens initiated centripetally, the vasculature of members of each whorl being connected radially; carpel number is 14 or fewer (Philipson 1970; Oskolski et al. 2010c). Tetraplasandra gymnocarpa and T. kavaiensis have secondarily more or less completely superior ovaries (Costello & Motley 2000, 2001, 2004 - see photograph on the cover of American J. Bot. 91(6) 2004). Hydroctyle, almost alone in the family, is highly polyploid (Yi et al. 2004).

For general information, see Philipson (1970), for embryology, about which I know little, see Mohana Rao (1973b), for wood anatomy, see Oskolski (1996), for pollen of Chinese Hydrocotyle, see Shu and She (2001), for gynoecial development in Seemannaralia, see Oskolski et al. (2010b), for flowers of Hydrocotyle, etc., see Leins and Erbar (2010), for some leaf anatomy, see de Villiers et al. (2010), for bark anatomy, see Kotina & Oskolski (2010), and for fruit anatomy, see Konstaninova and Suchorukow (2010).

Phylogeny. Basal Araliaceae may well be bicarpellate (see also Wen et al. 2001) and have simple leaves. Both these are features of the herbaceous Hydrocotyloideae (ex Apiaceae), which are sister to the rest of the family (Chandler & Plunkett 2004; Plunkett et al. 2004a; Nicolas & Plunkett 2009). The S.W. Australian genera Neosciadium and probably Homalosciadium also belong to Hydrocotyloideae (Andersson et al. 2006). Hydrocotyle has laterally flattened fruits with a sclerified (= woody) endocarp and stipules that are either cauline or are borne on the leaf base - and it also has trilacunar nodes (Sinnott & Bailey 1914). Trachymene (perhaps inc. Uldinia) is also to be placed in Hydrocotyloideae; morphologically it is rather similar to them, and although there is a carpophore in the fruit, it is undivided. For a phyogeny of Trachymene, see Henwood et al. (2010).

Astrotricha and Osmoxylon may be part of a polytomy at the node immediately above Hydrocotyloideae (see also Lee et al. 2008), while the position of Harmisopanax, which has fruits that are schizocarpic like those of Hydrocotyloideae, is also uncertain (Nicolas & Plunkett 2009).

For more details on the phylogeny of Aralioideae in particular, see Henwood and Hart (2001) and especially Wen et al. (2001), Plunkett et al. (2004a, c), and Lowry et al. (2004). Schefflera, with perhaps 1,600 species under 2/5 of which have been described (Frodin et al. 2010), is highly polyphyletic, and a number of major clades have become apparent in it - of which Schefflera s. str. is perhaps the smallest! These are circumscribed geographically and a number have morphological support; African plus Madagascan taxa form a clade, as do the some 250-300 neotropical species, the Asian species (these two clades are not far apart on the tree) and the Pacific species, and in part represent earlier infrageneric groupings (Plunkett et al. 2005, 2009, esp. 2010; Gostel et al. 2009; Fiaschi & Plunkett 2011; Frodin et al. 2010 for a summary), although with the inclusion of segregate genera. Lee et al. (2008) focused on relationships of Malesian Araliaceae; Osmoxylon was isolated.

Classification. For a checklist of the family, see Frodin and Govaerts (2003), although this is already very dated. Generic limits in Aralioideae need much attention (see above). The Pacific clade of Schefflera is to be called Plerandra, and Polyscias has been substantially enlarged (Lowry & Plunkett 2010).

[Myodocarpaceae + Apiaceae]: furanocoumarins +; inflorescence panicles or racemes.

MYODOCARPACEAE Doweld   Back to Apiales

Plants woody; ?coumarins; (sclereids in phelloderm); (vessel elements with scalariform perforation plates, numerous thin bars - Delarbrea); septate fibres 0; libriform fibres with very thick walls; axial parenchyma apotracheal (and paratracheal), diffuse-in-aggregates; rays homogeneous; leaves pinnately compound (simple), lamina margin entire (serrate), venation brochidodromous; pedicels articulated; K valvate, C imbricate; A inflexed in bud; ventral carpel bundles are fused bundles of adjacent placentae; nucellus?; fruits terete, fleshy, (dry, winged, seeds laterally flattened - Myodocarpus), secretory vesicles in mesocarp, endocarp with large oil ducts [different from vittae]; n = ?

2 (Myodocarpus, Delarbrea)/19. New Caledonia, E. Malesia, and Queensland, Australia (map: from van Balgooy 1993). [Photo - Habit]

Chemistry, Morphology, etc. Myodocarpus has a number of distinctive features of the flower and in particular fruit features (compound umbel; schizocarp), the latter of which may be associated with wind dispersal. Indeed, the mericarps are beautiful little samaras that at first sight are similar to those of Serjania! It has been suggested that in wood anatomy Myodocarpus is perhaps more like Cornaceae than any other members of the Apiaceae-Araliaceae complex, but in other features it is more like Apiaceae (Rodrigues C. 1957).

Some information is taken from Lowry (1986: Delarbrea), Raquet (2004: phylogeny and morphology), Plunkett et al. (2004c: general) and Liu et al. (2010: apomorphies); for wood anatomy, see Oskolski (1996).

Previous Relationships. This group used to be included in Araliaceae - Myodocarpeae.

APIACEAE Lindley, nom. cons.//UMBELLIFERAE Jussieu, nom. cons. et nom. alt.   Back to Apiales

Plant usu. herbaceous; pyranocoumarins, myricetin, mannitol +, umbelliferose [raffinose (trisaccharide) isomer] the storage carbohydrate; hydroxycoumarins, flavones 0; vessel elements aggregated; axial parenchyma scanty, paratracheal; stomata various; lamina vernation also supervolute, base ± encircling stem; K reduced to ring of teeth (obsolete), C free, clawed, valvate, usu. with inflexed tips, vein single, unbranched [?all]; A inflexed in bud; ventral carpel bundles are fused bundles of the same placenta, stigma usu. capitate; ovule (with -2 lateral layers of nucellar tissue), funicle "short"; fruit dry (fleshy), schizocarpic, mesocarp lignified, crystals single, rhombic, in small-celled inner layer, endocarp woody, 2(+) cell layers thick, sclereidal-fibrous; exotestal cells thin-walled.

434[approx. list]/3780 - 5 main groups below. World-wide, esp. N. temperate.

1. Mackinlayoideae Plunkett & Lowry

Plants woody (herbaceous); (centellose [oligosaccharide] - Centella); (cork cambium subepidermal - Centella); (vessel elements with scalariform perforation plates); apotracheal (+ paratracheal) parenchyma; (leaf irregularly palmately compound - Mackinlaya); (pedicel not articulated); (K petaloid); (nectary not divided; on style - Actinotus); nucellus?; (carpophore 0, but fused ventral bundles; rib oil ducts + [not Diposis, Klotzschia); n = 10.

7-9/93: Centella (40), Xanthosia (25), Actinotus (18). Most S. Pacific Rim, Centella esp. S. Africa, C. asiatica pantropical.

Synonymy: Actinotaceae Konstantinova & Melikian, Mackinlayaceae Doweld

[Platysace [Azorelloideae [Saniculoideae + Apioideae]]]: vessel elements with simple perforation plates; umbels compound; fruits dorsally compressed (not), carpophore +, mericarps separating at maturity [all characters at this node, or next?].

2. Platysace

(Oil ducts in ribs); K 0; cotyledons rounded, toothed; n = 8.

1(-2)/26. Australia, most in the southwest (map: FloraBase viii.2009).

[Azorelloideae [Saniculoideae + Apioideae]]: mesocarp vittae irregular, anastomosing and/or branching.

3. Azorelloideae Plunkett & Lowry

(Cork cambium deep-seated - Mulinum); (leaves compound), stipules +; nucellus "large", relatively persistent; megaspore mother cells 2-4, embryo sac tetrasporic, 16-nucleate [more than one embryo sac "type"]; fruit with wings/ribs [made up of the entire fruit wall, including a vascular bundle], lateral wings usually largest, (carpophore 0, fused ventral bundles +/0), (druses in outer mesocarp - Azorella), companion cells [oil canals associated with the vascular bundles] +, inner layer of endocarp fibres running longitudinally [?distribution]; n = 8-10, x = ?8.

21/155: Azorella (70: ?inc. Laretia, Mulinum). South American-Australian, Antarctic islands; Drusa glandulosa from the Canary Islands and Somalia! (map: from Bramwell 1972). [Photo - Habit.]

[Hermas [Saniculoideae + Apioideae]]: ?

Hermas

Umbels congested; fruit with rhomboidal crystals in mesocarp, ?druses, rib oild ducts +, vallecular vittae 0; carpophore +; n = 7.

1/8. South Africa.

[Saniculoideae + Apioideae]: basal leaf with pinnate venation [?level], stipules 0; ovules tenuinucellate [incompletely so], nucellar cap +, funicle "long"; fruit wings with mesocarp only, vascular bundles ar the base, (secondary [i.e. lateral] ribs +), mesocarp cells lignified, endocarp single cell layer thick, parenchymatous, (walls lignified), calcium oxalate as druses dispersed in mesocarp and around commissure, rhomboidal crystals 0.

4. Saniculoideae Burnett

Kaurene-type terpenoids +; (cork cambium outer cortical); (nectary outside A); style separated from disc by a narrow groove; ribs with oil ducts/cavities; cotyledons rounded.

10/335. World-wide (map: see Meusel et al. 1978; Hultén & Fries 1986; Wörz 2011).

4a. Steganotaenieae C. I. Calviño & S. R. Downie

Plant woody; phelloderm with chambered crystalliferous cells; dilation of secondary phloem by expansion of axial parenchyma [not ray cells]; basal leaves appearing well before flowering; fruits heteromericarpic, 2-3 winged [wings exo- and mesocarp alone], rib secretory ducts/cavities much expanded, carpophore +, (dispersed mesocarp druses 0); n = ?

2/2-3. Tropical Africa, S.W. Cape.

4b. Phlyctidocarpeae Magee, Calviño, Liu, et al.

Umbels pedunculate; fruits bristly, ribs bifurcate, vittae +; n = ?

1/1: Phlyctidocarpa flava. Namib desert.

4c. Saniculeae Burnett

(R)-3'-O-ß-D-glucopranosylrosmarinic acid +; leaves (compound), lamina often broad, teeth with hairy or spiny tips; umbels simple (a capitulum - Eryngium; pseudoracemose - Sanicula), with showy inflorescence bracts; pedicels ± 0; (flowers blue), carpellate flowers sessile; fruit scaly or spiny, carpophore 0, (rib secretory ducts/cavities 0), (dispersed crystals throughout mesocarp 0), endocarp not lignified; n = 8 (9, 11, 12).

8/333: Eryngium (250). World-wide (map: see Meusel et al. 1978; Hultén & Fries 1986).

Synonymy: Eryngiaceae Berchtold & J. Presl, Saniculaceae Berchtold & J. Presl

5. Apioideae Seemann

Flavones, methylated flavonoids, furanocoumarins, phenylpropenes +; leaves usu. compound; (outer flowers of umbel monosymmetric); hypostase +, (postament +); carpophore free, bifid [mericarps attached at apex], (tanniniferous epidernal cells 0 - euapioids), intrajugal oil ducts small/0, vallecular vittae +, (0 - Lichtensteinieae et al.); seed reserves manna [?right place]; x = 11; cotyledons (1), various.

Ca 380/3200. Worldwide, esp. N. Temperate.

Lichtensteinieae Magee, Calviño, Liu, et al.

(Basal leaves appearing well before flowering); (fruits heteromericarpic), (endocarp woody, druses 0 - Choritaenia), oil ducts/cavities in the ribs +

The Rest: fruits with vittae.

Annesorhizeae Magee, Calviño, Liu, et al.

(Plant woody); (fruits heteromericarpic), vascular bundles highly lignified.

Euapoids

Druses on commissural side of mericarp only, or none.

Heteromorpheae M. F. Watson & Downie

(Plant woody); vessel walls with helical thickenings; fibres septate; (involucral bracts dentate); (K well developed); fruits (heteromericarpic), not or slightly dorsiventrally or laterally compressed

11/36: Anginon (12). Africa (esp. the southwest), Madagascar, to the Yemen (Map: from Winter & van Wyk 1996; Allison & van Wyk 1997).

Bupleureae Sprengel

(Plant woody); vessel walls with helical thickenings; fibres septate; leaves simple, margins entire, (venation parallel); (umbel sessile; K present - ex Hohenackeria); pollen usu. rhomboidal; cotyledons linear, single veined, glabrous; n = 7, 8.

1/190. Europe and North Africa, to the Canary Islands, East Asia and N.W. North America, also South Africa (Map: from Meusel et al. 1978; GBIF iv.2010).

Synonymy: Bupleuraceae Berchtold & J. Presl

The Rest: druses in fruit wall absent.

360/3045: Ferula (175), Pimpinella (150), Angelica (110), Seseli (110), Peucedanum s.l. (110), Lomatium (74), Heracleum (65), Chaerophyllum (60), Arracacia (55), Ligusticum (50). (map: see Meusel et al. 1978; Hultén & Fries 1986 - incomplete).

Synonymy: Ammiaceae Berchtold & J. Presl, Angelicaceae Martynov, Caucaulidaceae Berchtold & J. Presl, Coriandraceae Burnett, Daucaceae Martynov, Ferulaceae Saccardo, Imperatoriaceae Martynov, Lagoeciaceae Berchtold & J. Presl, Pastinacaceae Martynov, Pimpinellaceae Berchtold & J. Presl, Scandicaceae Berchtold & J. Presl, Selinaceae Berchtold & J. Presl, Sileraceae Berchtold & J. Presl, Smyrniaceae Burnett

• Apiaceae are recognisable by their usually herbaceous habit and compound leaves with broad, sheathing bases; inflorescences that are usually umbels of umbels, rarely heads; and polypetalous flowers usually with a minute calyx, clawed petals with incurved apices, and two carpels; the fruits are dry and schizocarpic.

• Saniculoideae have usually undivided leaves with hairs or spiny tips to the teeth, sessile and spiny or scaly fruits, an often apparently more or less simple umbel or head, and there is no free carpophore.

• Apioideae usually have more or less finely-divided leaves, compound umbels, and the usually pedicellate fruit has a free, bifid carpophore.

Evolution. Divergence & Distribution. Fruits from the late Cretaceous (Maastrichtian) of Wyoming and Montana (Carpites) have been assigned to Apiaceae (Manchester & O'Leary 2010). Apioideae are likely to have evolved in Southern Africa, but although a number of taxa from there have a woody habit, the ancestral condition for this subfamily, at least, is likely to be herbaceous (Calviño et al. 2006). Apomorphies for these basal groups in Apioideae are becoming clarified; see Magee et al. (2010a) for some details.

As relationships get sorted out, biogeographic studies become possible. Spalik et al. (2010) looked at wide disjunctions in Apioideae, providing series of dates for the nodes; i.a. they found that Lilaeopsis brasiliensis and L. mauritiana were very close, even though they were separated by the Atlantic Ocean and the African continent...

Plant-Animal Interactions. Caterpillars of Papilionidae-Papilionini butterflies are notably common (ca 13% of all records) on Apiaceae, perhaps shifting here from Aristolochiaceae (Fordyce 2010; see also Berenbaum & Feeny 2008). Interestingly, they are not found on either Pittosporaceae or Araliaceae; thus they will not eat Hydrocotyle (here Araliaceae), many of the larvae of Papilio ajax tested absolutely refusing to eat it (see also Dethier 1941; Ehrlich & Raven 1967). Linear fumarocoumarins are often phototoxic but are tolerated by caterpillars that will not eat plants with the non-photoxic linear coumarins (Berenbaum & Feeney 1981). Microlepidopteran larvae of the Elachistidae - Depressariinae are common on Apiaceae, although they may have initially been associated with rosids and have also colonized some Asteraceae (Fetz 1994 for host plants; Berenbaum & Zangerl 1998 for the chemistry of the [co]evolution of resistance; Berenbaum & Passoa 1999 for a phylogeny). There has been a diversification of agromyzid dipteran leaf miners in north temperate Apiaceae; they were previously on Ranunculaceae, also a group with noxious secondary metabolites (Winkler et al. 2009). For general insect-umbellifer relationships, see Berenbaum (1990) and Sperling and Feeny (1995).

Floral Biology & Seed Dispersal. All the flowers in an umbel open more or less simultaneously. In a number of Saniculoideae and a few Hydrocotyloideae in particular the inflorescence bracts function as petals, the rest of the inflorescence being much reduced and the whole looking more or less like a simple flower (Froebe & Ulbrich 1978), indeed, inflorescence morphology can be very complex (e.g. Froebe 1979). The dark flower in the centre of the umbel of taxa like Daucus carota may attract flies that pollinate the flowers (Westmoreland & Muntan 1996).

Platysace and some Mackinlayoideae have myrmecochorous fruits (Lengyel et al. 2010).

Vegetative Variation. Variation in leaf morphology, even within Apioideae, is considerable. Thus the small circum-Pacific genus Oreomyrrhis includes species with ordinary-looking highly dissected leaves, leaves with a series of almost tooth-like leaflets on either side of the rachis, linear leaves, sometimes lobed at the apex, although the lobes are not articulated, and small, undivided leaves. In the last case the plant is tussock-forming and almost moss-like - specimens have even been identified as Centrolepidaceae (= Restionaceae), a monocot! All these leaf morphologies are found on the mountains of New Guinea. Although the genus is probably monophyletic, it is well embedded in Chaerophyllum, a genus hitherto thought to be fairly well understood (Chung et al. 2005; Chung 2007). Lilaeopsis occidentalis and Oxyopolis greenmanii have linear, terete leaves that are marked by articulations at intervals. These leaves are comparable with the rhachis of compound leaves, hydathodes borne at the articulations representing much reduced and modified pinnae (Kaplan 1970b, cf. esp. Figs 3E and 6A). Other North American taxa have similar leaves, and these leaves appear to have evolved several times (Feist & Downie 2008). Bupleurum rotundifolium has almost orbicular, entire, perfoliate leaves, hence its common name, thorow wax.

There is considerable variation in seedling morphology. A number of taxa have cryptogeal germination in which the plumule ends up under ground as part of the germination process; associated with this, monocotyly is also quite common (see Haccius 1952b; Cerceau-Larrival 1962; Haines & Lye 1979).

Chemistry, Morphology, etc. Gums and resins are scattered in the family. For the distinctive rosmarinic acid glucoside found in Saniculoideae-Saniculeae, see Olivier et al. (2008). Oskolski et al. (2010a) describe wood and bark anatomy of Steganotaenieae in particular and Saniculoideae in general. Peripheral collenchyma in the stem is often especially well developed, and petiole anatomy is very variable and complex (e.g. Metcalfe 1950). Taxa such as Foeniculum have stipules of sorts.

The usually compact inflorescence units of Saniculoideae may be best interpreted as a group of reduced umbellules (Froebe 1964, 1971), although they are called simple umbels above. Centella has a few branches from the petal bundle (Gustafsson 1995); petal vasculature may repay attention. Spichiger et al. (2002) show the two carpels as being collateral. According to Eyde and Tseng (1971), whether the ventral carpel bundles are fused bundles of adjacent placentae or are from the same placenta varies within Apiaceae without any particular systematic significance. Van Tieghem (1898) noted that in Apiaceae the ascending ovule aborts and the pendulous ovule persists, however, other reports suggest that both ovules are pendulous (Philipson 1970).

For stomata, see Guyot 1971 and referenes - value slight?), for chemistry, see Hegnauer (1971) and Berenbaum (2001), for inflorescences of Saniculoideae and Hydrocotyloideae in particular, see Froebe (1964, 1969 respectively), for those of Eryngium, see Harris (1999), for wood anatomy in Apioideae-Heteromorpheae, see Oskolski and van Wyk (2008) and in Mackinlayoideae, see Oskolski and van Wyk (2010), for the distribution of the hypostase, see Gupta (1970), for embryo sac morphology and fruit anatomy, esp. of genera in the old Hydrocotyloideae, see Tseng (1967), for a useful discussion of characters mainly in the context of Southern African taxa, see Burtt (1991a), for genera, old style, see Pimenov and Leonov (1993), for pollen of Chinese Apiaceae, see Shu and She (2001), for chromosome number and morphology, see Pimenov et al. (2003), for floral development, see Leins and Erbar (2004b), for vittae and druses in the fruits, see Liu et al. (2007), and for fruit anatomy of Azorelloideae, see Liu et al. (2009). There is much useful information in Chandler and Plunkett (2003, 2004) and also in all four numbers of Plant Divers. Evol. 128. 2010, inc. Stepanova & Oskolski (2010: Bupleurum).

Phylogeny. The old Hydrocotyloideae are hopelessly polyphyletc, and their members now occur in several quite separate clades of which most are still in Apiaceae (Nicolas & Plunkett 2009). Some genera of Mackinlayoideae used to be in Araliaceae - Mackinlayeae, others in Apiaceae - Hydrocotyloideae; included are Apiopetalum, Mackinlaya, Micropleura, Xanthosia. See Melikian and Konstantinova (2006) for discussion on the gynoecial structure of Actinotus which they consider to be so different from that of other Apiaceae that it merits the genus being placed in its own family; it is to be included in Mackinlayoideae, although its position within the clade is unclear (Nicolas & Plunkett 2009).

Platysace - perhaps to include Homalosciadium - is not a member of Mackinlayoideae, where it had been placed (e.g. Chandler & Plunkett 2004). It seems to be sister to other Apioideae in some analyses (Henwood & Hart 2001; Andersson et al. 2006), but a position rather deep in the tree sister to [Azorelloideae [Saniculoideae + Apioideae]] is strongly supported (Nicolas & Plunkett 2009), although Soltis et al. (2011: but sampling) found that it was moderately supported as sister to Mackinlaya. The positions of Klotzschia ("distinctive fruits") and Hermas, both of which used to be in Hydrocotyloideae, are also unclear (Andersson et al. 2006; Calviño et al. 2006, 2008); the former may go with Azorelloideae (see below), and the latter has some similarities with Saniculoideae. However, Hermas, another South African endemic, is unlikely to be placed within any currently recognized subfamily (Nicolas & Plunkett 2009); there is some support for a position as sister to [Saniculoideae + Apioideae], and I have tentatively placed it there.

For the phylogeny of Azorelloideae, in which are to be placed about half the genera that used to be included in Hydrocotyloideae, see Downie et al. (1998, 2000a, 2001), Mitchell et al. (1999), Plunkett & Lowry (2001), Henwood and Hart (2001: the Bowlesia clade), Chandler and Plunkett (2004), Andersson et al. (2006) and Nicolas and Plunkett (2009), the latter of which see for details. Stilbocarpa used to be in Araliaceae, but it is probably sister to the Andean Huanaca. Klotzschia may also belong here, but its position is not stable and it may be a member of Apioideae; this genus aside, Diposis is sister to other Azorelloideae (Nicolas & Plunkett 2009). Bowlesia lacks petroselenic acid, but it was apparently the only genus of this group studied (Kleiman & Spencer 1982).

The monophyly of Saniculoideae (except Lagoecia, now in Apioideae) is upheld in all molecular analyses, and details of relationships within it are given by Valiejo-Roman et al. (2002). In some analyses the African ex-hydrocotyloid Arctopus (see Magin 1980 for floral development) is sister to other Saniculoideae, and the woody Steganotaenia and Polemanniopsis, and perhaps Lichtensteinia, were probably also part of the same clade (Downie et al. 2001; van Wyck 2001; M. Liu et al. 2003; Plunkett et al. 2004c); at least some of the latter genera have a slightly lignified endocarp, apparently alone in both Saniculoideae and Apioideae (M. Liu et al. 2004). Calviño et al. (2006, esp. 2007 for a good general discussion of variation), however, expressed reservations about this expanded - and characterless - Eryngioideae, while Calviño and Downie (2007, but cf. Mageee et al. 2010) found that the clade could be circumscribed satisfactorily so long as Lichtensteinia was excluded and placed in Apioideae; they recognised two tribes, both well supported and with unique indels. Nicolas and Plunkett (2009) found that a clade including Lichtensteinia and Choritaenia were weakly supported as being sister to other Saniculoideae; on the other hand, although this set of relationships has not been upheld, the monotypic Phlyctidocarpa does seem to be a member of Saniculoideae, although its exact position there is unclear (Magee et al. 2010a). Oskolski et al. (2010a, which see for more characters) describe wood anatomy of some woody Saniculoideae; although the subfamily could not be characterised, Steganotaenieae were more or less distinct. Carpophores, chromosome numbers other than 8, and inflorescences that are not condensed (all in African taxa) could be plesiomorphic in the clade (see also Calviño et al. 2008a; Kadereit et al. 2008). The large genus Eryngium has separate New and Old World clades (Calvinño et al. 2008b, 2010); a recent morphological analysis suggested that four unrelated species (in the system later used in the same paper) made up a series of basal pectinations, although there was no strong support for this topology (Wörz 2011).

Within Apioideae, some taxa are woody, e.g. the Southern African Bupleurum fruticosum and a number of other Southern African taxa (Calviño et al. 2006); Myrrhidendron, from Central America and Colombia, is also woody, but is not related. Relationships at the base of the subfamily are very pectinate and are something like [Lichtensteinia [Annesorhiza clade [Heteromorpheae (some woody; vessel element walls with helical thickenings) [Bupleurum + The Rest]]]] (Downie & Katz-Downie 1999; Plunkett et al. 2004; Calviño et al. 2006; Magee et al. 2008, also a revision of Ezosciadium; Magee et al. 2010a). Apart from the position of Lichtensteinia, in some analyses sister to [Saniculoideae + Apioideae], relationships in Nicolas and Plunkett (2009) are similar; above Bupleurum on the tree was Neogoezia. Heteromorpheae include a small clade of ca 14 species currently placed in seven genera - something of an overkill - that is largely restricted to Madagascar (Downie et al. 2010). Indeed, these "basal" clades of Apioideae are made up largely of Southern African genera (see Burtt 1991a for information on southern African taxa), although some occur elsewhere in Africa and one genus gets to Europe; as mentioned, they are now strongly supported as successively sister to the rest of the subfamily, and, as Calviño et al. (2006) note, this has considerable implications for synapomorphy positions. Note that in some analyses the Annesorhiza clade appeared to be allied with Heteromorpheae (including Pseudocarum, which has branching/anastomosing vittae); Bupleurum also has branching vittae and is strongly supported as sister to the remainder of the subfamily (Calviño et al. 2005, 2006). For relationships within Bupleurum, see Neves and Watson (2004). /p>

Apioideae also include Lagoecia, with its quite well developed calyx and 1-seeded fruits, which was previously associated with Saniculoideae (Magion 1980). For other relationships within Apioideae, see e.g. Downie et al. (2000a, b, 2001, 2002), Hardway et al. (2004), Plunkett and Downie (2000 - variation in size of chloroplast inverted repeat characterises a large clade in Apioideae), Spalik and Downie (2001a, b), Sun and Downie (2004, 2010a, b [perennial W. North American members of the subfamily, a variety of morphological, also molecular, analyses]), Sun et al. (2004: Cymopterus and Lomatium about as polyphletic as you can get), Kurzyna-Mlynik et al. (2008: Ferula, somewhat paraphyletic, and relatives), Downie et al. (2008: Oenantheae), Zhou et al. (2008: China), Ajani et al. (2008: Iran), Winter et al. (2008: Africa), Sun et al. (2008: Ligusticum in China), Degtjareva et al. (2009: Bunium polyphyletic, monocotyledonous species separate), Spalik et al. (2009: Sium area), Magee et al. (2009: especially Cape genera), Magee et al. (2010b - Pimpinella), Logacheva et al. (2010: Tordylieae), and Yu et al. (2011: Chinese Heracleum, the genus is polyphyletic).

Classification. The subfamilial classification of Plunkett et al. (2004c) is followed here, but additions will be needed given the positions taken by some ex Hydrocotyloideae in the tree recovered by Nicolas and Plunkett (2009). Downie et al. (2010) build on Plunkett et al.'s earlier classification, suggesting tribes and subtribes for Apioideae, and listing genera in these taxa; there are some unnamed groups of genera. Polyphyly is dealt with as satisfactorily as it can be. For tribes in Saniculoideae and in the basal pectinations in Apioideae, see Magee et al. (2010a); five of these tribes are new (and all are small) and I have informally combined Marlothielleae and Choritaenieae (both monospecific) with Lichtensteinieae above.

Indeed, classical generic and tribal limits in Apioideae are something of a disaster area. The traditional tribal and generic classification was based primarily on fruit morphology and is problematic; convergence of fruit architecture as adaptations to modes of fruit dispersal has resulted in many non-monophyletic groupings. Recent studies using molecular techniques are demonstrating the problems with the traditional classifications and are beginning to resolve generic and tribal affinities (see Downie et al. 2010). For instance, 13/18 genera for which two or more sequences were included in in a study by Downie et al. (2000b) were found not to be monophyletic. The problem is further compounded by the disproportionately large number of mono- or di-typic genera (see also Spalik et al. 2001; Valiejo-Roman et al. 2006; Spalik & Downie 2007). Indeed, just about all the papers dealing with phylogenetic relationships in Apioideae (see above) have implications for generic limits there.

Thanks. I am particularly indebted to Mark Watson for comments on Apiaceae s.l.; mistakes remain mine.