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, apex multicellular, xylem exarch, branching endogenous; arbuscular mycorrhizae +; shoot apical meristem multicellular; stem with ectophloic eustele, endodermis 0, xylem endarch, branching exogenous; vascular tissue in t.s. discontinuous by interfascicular regions; vascular cambium + [xylem ("wood") differentiating internally, phloem externally]; wood homoxylous, tracheids +; tracheid/tracheid pits circular, bordered; sieve tube/cell plastids with starch grains; phloem fibers +; stem cork cambium superficial, root cork cambium deep seated; nodes ?; stomata ?; leaf vascular bundles collateral; leaves spiral, simple, axillary buds?, prophylls [including bracteoles] two, lateral, veins -5 mm/mm² [mean for all non-angiosperms 1.8]; plant heterosporous, sporangia eusporangiate, on sporophylls, sporophylls aggregated in indeterminate cones/strobili; true pollen [microspores, i.e. no distal pore for release of gametes] +, grains mono[ana]sulcate, exine and intine homogeneous, ovules unitegmic, crassinucellate, megaspore tetrad tetrahedral, only one megaspore develops, megasporangium indehiscent; male gametophyte development first endo- then exosporic, tube developing from distal end of grain, to ca 2 mm from receptive surface to egg, gametes two, with cell walls, with many flagellae; female gametophyte endosporic, initially syncytial, walls then surrounding individual nuclei; seeds "large", first cell wall of zygote transverse, embryo straight, endoscopic [suspensor +], short-minute, with morphological dormancy, white, cotyledons 2; plastid transmission maternal; two copies of LEAFY gene, PHY gene duplication [N/O//A/C and P//BE lines], mitochondrial nad1 intron 2 and coxIIi3 intron present.

MAGNOLIOPHYTA

Plant woody, evergreen; lignans, O-methyl flavonols, dihydroflavonols, triterpenoid oleanane, non-hydrolysable tannins, quercetin and/or kaempferol +, apigenin and/or luteolin scattered, cyanogenesis via tyrosine pathway [ANITA grade?], lignins derived from both coniferyl and sinapyl alcohols, containing syringaldehyde [in positive Maüle reaction, syringyl:guaiacyl ratio less than 2-2.5:1], and hemicelluloses as xyloglucans; root apical meristem intermediate-open; root vascular tissue oligarch [di- to pentarch], lateral roots arise opposite or immediately to the side of [when diarch] xylem poles; origin of epidermis with no clear pattern [probably from inner layer of root cap], trichoblasts [differentiated root hair-forming cells] 0; stem with 2-layered tunica-corpus construction; wood fibers and wood parenchyma +; reaction wood ?, with gelatinous fibres; starch grains simple; primary cell wall mostly with pectic polysaccharides; tracheids +; sieve tubes eunucleate, with a sieve plate and cytoplasm with P-proteins, companion cells from same mother cell that gave rise to the sieve tube; nodes unilacunar [1:?]; stomata with ends of guard cells level with pore, paracytic, outer stomatal ledges producing vestibule; leaves with petiole and lamina [the latter formed from the primordial leaf apex], development of venation acropetal, 2ndary veins pinnate, fine venation reticulate, veins (1.7-)4.1(-5.7) mm/mm², endings free; flowers perfect, polysymmetric, parts spiral [esp. the A], free, development in general centripetal, numbers unstable, P not differentiated, outer members not enclosing the rest of the bud, smaller than inner members, A many, with a single trace, introrse, filaments stout, anther ± embedded in the filament, tetrasporangiate, dithecal, with at least outer secondary parietal cells dividing, each theca dehiscing longitudinally by action of hypodermal endothecium, endothecial cells elongated at right angles to long axis of anther, tapetum glandular, binucleate, microspore mother cells in a block, microsporogenesis successive, walls developing by centripetal furrowing, pollen subspherical, binucleate at dispersal, trinucleate eventually, tectum continuous or microperforate, ektexine columellar, endexine thin, compact, lamellate only in the apertural regions, pollen germinating in less than 3 hours, tube elongated, growing at 80-600 µm/hour, with callose plugs and callose-based walls, penetrating between cells, siphonogamy, penetration of ovules within ca 18 hours, distance to first ovule 1.1.-2.1 mm, nectary 0, G free, several, ascidiate, with postgenital occlusion by secretion, few [?1] ovules/carpel, ovules marginal, anatropous, bitegmic, [outer integument often largely subdermal in origin, inner integument dermal], micropyle endostomal, integuments 2-3 cells thick, megasporocyte single, megaspore lacking sporopollenin and cuticle, chalazal, female gametophyte four-celled [one-modular, nucleus of egg cell sister to one of the polar nuclei], stylulus short, hollow, stigma ± decurrent, dry [not secretory]; P deciduous in fruit; seed exotestal; double fertilisation +, endosperm diploid, cellular [first division oblique, micropylar end initially with a single large cell, chalazal end more actively dividing], copious, oily and/or proteinaceous, embryo cellular ab initio, minute; germination hypogeal, seedlings/young plants sympodial; Arabidopsis-type telomeres [(TTTAGGG)_n]; whole genome duplication, single copy of LEAFY and RPB2 gene, knox genes extensively duplicated [A1-A4], AP1/FUL gene, paleo AP3 and PI genes [paralogous B-class genes] +, with "DEAER" motif, SEP3/LOFSEP and PHYA + C/PHYB + E gene pairs.

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, there is considerable variation between families in particular for several of these characters, and also because details of relationships among gymnosperms will affect the level at which some of these characters are pegged.

NYMPHAEALES [AUSTROBAILEYALES [[CHLORANTHALES + MAGNOLIIDS] [MONOCOTS [CERATOPHYLLALES + EUDICOTS]]]]: vessels +, elements with scalariform perforation plates; ?genome duplication; "DEAER" motif in AP3 and PI genes lost, gaps in these genes.

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

ROSIDS: embryo long; genome duplication; chloroplast infA gene defunct, mitochondrial coxII.i3 intron 0.

ROSID I/FABIDAE: Endosperm scanty.

CELASTRALES [OXALIDALES + MALPIGHIALES]: seed exotegmic, cells fibrous.

OXALIDALES + MALPIGHIALES: ?

OXALIDALES Heintze  Main Tree, Synapomorphies.

Characters? - 7 families, 60 genera, 1815 species.

Evolution. Oxalidales are perhaps 91-88 million years old (Huaceae not included), with divergence of crown group members beginning 77-72 million years before present (Wikström et al. 2001). Other estimates are a little older, thus Wang et al. (2009: penalized likelihood dates) suggested that the same stem group originated 109-84 million years ago, while crown group divergence began 74-57 million years ago.

Chemistry, Morphology, etc. Leaves of Cunoniaceae and Elaeocarpaceae can be almost indistinguishable. Diplostemony does not occur in the order; the androecium of Cunoniaceae is obdiplostemonous, according to Huber (1963), and so agrees with that of Oxalidaceae (and Brunelliaceae [Orozco 2002] and Connaraceae). Connaraceae and Brunelliaceae have ovaries with adaxial furrows (cf. the ventral slit: Matthews & Endress 2002b). Is the distribution of taxa that have carpels with five vascular traces of any interest?

Some information is taken from Nandi et al. (1998). Much information on floral morphology and development for the whole order is provided by Matthews and Endress (2002b, summarized in 2006b, and with illustrations of fringed and lobed petals in Cunoniaceae and Elaeocarpaceae); Matthews and Endress (2002b) note the filaments are longer than the anthers in bud here (but not in Elaeocarpaceae), as in the unrelated Anisophylleaceae (Cucurbitales).

Phylogeny. A somewhat unexpected association of families. Molecular data suggest Oxalidaceae and Connaraceae in particular are close (Price & Palmer 1993; Williams et al. 1994; Fernando et al. 1995, etc.), and this position also has strong morphological support; the other families may form a clade sister to them (e.g. Zhang & Simmons 2006, Cephalotaceae not included). For the relationships of Brunelliaceae, see Bradford and Barnes (2001), although morphological analyses (Miranda-Esquivel 2001; Orozco 2001a; Orozco Pardo 2002) suggest various groupings of Brunelliaceae and Cunoniaceae intermixed. The family pair [Brunelliaceae + Cephalotaceae] is suggested by Davis et al. (2004) and Crayn et al. (2006).

Zhang and Simmons (2006: see also Soltis et al. 2007a) found that Huaceae were sister to the other Oxalidales they examined, with quite strong support (jacknife values over 80%); they suggest that Huaceae should be included in Oxalidales. Zhu et al. (2007) found 76% (maximum parsimony) and 82% (maximum parsimony) bootstrap support for this position when the mitochondrial matR gene was examined, but support was lost when two chloroplast genes were added, and support was only weak in the recent analysis of wang et al. (2009). All in all, however, Huaceae seem to be finding a more fixed place on the tree, and movement is in order. However, they do do not seem to have even the rather unimpressive morphological features that characterize other Oxalidales.

Previous relationships. Although the flowers of Anisophyllea (Anisophylleaceae - Cucurbitales) are remarkably similar to those of Ceratopetalum (Matthews et al. 2001; cf. also Matthews & Endress 2004, 2006b), and there are perhaps comparable similarities in the fossil Platydiscus peltatus (Schönenberger et al. 2001a; see also Schönenberger & von Balthazar 2006), this is unlikely to reflect a close relationships between the two; Ceratopetalum is somewhat embedded in Cunoniaceae (see below) and the two families are in very different clades.

Includes Brunelliaceae, Connaraceae, Cephalotaceae, Cunoniaceae, Elaeocarpaceae, Huaceae, Oxalidaceae.

Synonymy: Connarales Reveal, Cephalotales Nakai, Cunoniales Hutchinson, Huales Doweld, Tremandrales R. Brown

HUACEAE A. Chevalier

Evergreen, woody (lianes); ellagic acid?; hairs stellate or peltate (unequally 2-armed); cork?; cambium storying?; vessel elements with simple (scalariform) perforations; phloem with broad rays; cristarque cells +, petiole vasculature complex; stomata paracytic, cuticle waxes 0; leaves two-ranked, margins entire, basal glands on margin or abaxial surface, (strong vein pair from the very base), stipules +; inflorescence axillary, fasciculate; (flowers 4-merous), K valvate or completely connate, C clawed or strongly obovate, A 2x C, pollen porate, nectary?, G [5], unilocular, with 1 (4-)6 basal ovules, micropyle?, style +, stigma punctate; fruit a ?septicidal capsule or drupe, pericarp with stony layer in middle; seed 1, testa (hairy - Hua) with vascular bundles, exotegmen of lignified palisade cells; endosperm copious, ?development, cotyledons flattened; n = ?

2[list]/3. Tropical Africa (Map: from Heywood et al. 2007).

• Huaceae are evergreens, usually trees, that are recognizable by their two-ranked leaves the blades of which have a very fine, boxy reticulum; there are small glands at the very base of the lamina. The cauline stipules are early deciduous. The plant smells of garlic.

Chemistry, Morphology, etc. Poorly known. Hua has long-clawed petals with peltate blade, unremarkable anthers, a single ovule, and the fruit is a capsule; Afrostyrax has strongly obovate petals, aristate anthers dehiscing from the apex, and the fruit is a drupe. For additional information, see Baas (1972: anatomy) and Hegnauer (1989: a little chemistry).

Previous Relationships. The family has been of uncertain position in the past, being included in Malvales (e.g. Baas 1972; Takhtajan 1997), hardly unsurprisingly less out of place in the more heterogeneous Violales (Cronquist 1981), or left unplaced in the rosids by the A.P.G. (1999, 2003).

[[Connaraceae + Oxalidaceae] [Cunoniaceae [Elaeocarpaceae [Brunelliaceae + Cephalotaceae]]]]: vessel element type?; mucilage cells +; stomata ?; leaves odd-pinnate to tri(uni)foliolate; micropyle bistomal, styles +, stigma secretory; integument multiplicative, endotesta crystalliferous and palisade, exotegmen also tracheidal.

Connaraceae + Oxalidaceae: plant construction sympodial; benzoquinone rapanone +, ellagic acid 0; roots diarch [lateral roots 4-ranked]; wood rays uniseriate; sieve tube plastids with protein crystalloids; calcium oxalate druses 0; cuticle wax platelets as rosettes; leaflets articulated, margins entire, 2ndary veins pinnate to palmate, stipules 0; C postgenitally near-basally united, with uniseriate glandular hairs, nectary extrastaminal, A (with dimorphic and trimorphic heterostyly), of two whorls of different lengths, connate basally, (5, with antepetalous A staminodial), with uniseriate glandular hairs, (pollen colpate; endothelium +; stigma with rounded multicellular ornamentations); K persistent in fruit; exotesta ± fleshy.

Chemistry, Morphology, etc. Sieve tube plastids may have protein crystalloids + starch [Connaraceae], crystalloids + fibers + starch [both], or crystalloids alone [Oxalis].

CONNARACEAE R. Brown, nom. cons.   Back to Oxalidales

Shrubs or lianes (trees); hairs uniseriate, submesifixed or not; wood commonly siliceous or with SiO₂ grains; (nodes 5:5, 7:7); stomata variable; leaves two-ranked or spiral; (plants dioecious; flowers 4-merous), pedicels articulated; (K connate; nectary 0), A connate or not, G 1 (3) 5 (7, 8), 2 collateral [type?] near-basal ovules/carpel, funicle 0, micropyle exostomal, stigmas capitate, ?type; fruit a follicle (also dehiscing abaxially; drupe), often only 1 G developing, sepals persistent, ± indurated; seed 1 (2), testa black, vascularised, sarcoexotesta ± developed, exotesta various, inc. palisade (lignified); endosperm 0 to abundant, oily; n = 14, 16.

12[list]/180: Connarus (80), Rourea (40-70). Pantropical, especially Old World (Map: from Leenhouts 1958; Heywood 1978 [Africa]; Forero 1983). [Photo - Flower, Fruit.]

• Connaraceae are mostly woody lianes that twine in the apical parts of the innovations. They may be recognised by their pinnately compound, exstipulate leaves with transversely-ridged petioles, and ± ridged or keeled follicles with black and contrasting orange to red seeds. The follicles are usually single and swell to almost mature size well before the seeds are developed; the ripe seeds are partly squeezed out of the follicle. The small, radially symmetric flowers with stamens of two lengths are rather undistinguished.

Chemistry, Morphology, etc. The plants are often poisonous. There are often five traces to each carpel. The ovules may be straight or anatropous. Number of nuclei in pollen? There is much useful information in Jongkind and Lemmens (1989) and Lemmens et al. (2004); Dickison (1971) described carpel anatomy.

Previous Relationships. The cuticle waxes of Connaraceae are similar to those of Fabaceae-Fabales (Ditsch & Barthlott 1994) with which Connaraceae have frequently been confused. However, the two are not particularly close, and can usually be distinguished because the Connaraceae lack stipules and have rather small, polysymmetric flowers with ten stamens of two different lengths, a combination of features unknown in Fabaceae.

Synonymy: Cnestidaceae Rafinesque

OXALIDACEAE R. Brown, nom. cons.   Back to Oxalidales

Trees to herbs (lianes); tannins +; petiole bundle(s) annular (with medullary bundles); mucilage cells?; juice acrid, soluble calcium oxalate accumulation; stomata paracytic; leaves spiral (two-ranked), (stipules +, small), colleters + [Oxalis]; inflorescence cymose, pedicels articulated, C contorted, often clawed, anthers extrorse, nectaries often glands opposite petals, G [(3-)5], (1-)2-many often tenuinucellate ovules/carpel, both integuments at least 3 cells thick, (archesporium multicellular), stigmas spathulate/capitate; fruit a ± ribbed/angled capsule or berry; seed (subruminate), often with mucilaginous testa, explosive, (endotesta walls thickened; not palisade), (exotegmen 2-layered), [testa and tegmen less differentiated when fruit a berry]; endosperm +, starchy (0), embryo large, green or white [Oxalis]; n = (5-)7(-12).

6[list]/770: Oxalis (700: some tristylous), Biophytum (50). Usu. tropical or subtropical: species like Oxalis corniculata are very weedy and widespread (Map: from Hultén 1958, 1971; Hultén & Fries 1986; Lourteig 2000 and references; GBIF Biophytum vii.2008; FloraBase vii.2008 - details of distribution uncertain especially in Africa). [Photo - Flower]

• Oxalidaceae may be recognised by their usually compound leaves with pulvinate leaflets; their leaflets are entire and often have subpalmate venation. The inflorescence is either cymose or has cymose branches, the flowers are heterostylous, the corolla is clawed, and soon withers or is deliquescent, the stamens are obviously of two lengths, and the styles have capitate stigmas. The fruit is often a more or less ribbed, loculicidal capsule.

Evolution. Oxalis in the Cape region is a major element of the geophytic flora there (Procheŝ et al. 2006). Of the some 200 species in southern Africa, about 180 grow in the Greater Cape floristic region. Diversification of Oxalis in the Fynbos began about (31-)15.75 million years ago, that in the succulent karoo some (20-)10 million years ago (Verboom et al. 2009). All are bulbous, some species having very distinctive methods of vegetative reproduction and perennation, and they show more vegetative than floral variation (Oberlander et al. 2009). Elsewhere Oxalis is most diverse in South America. Bulbs of African species of Oxalis are tunicate, while New World species that are bulbous have scaly bulbs; there are few other non-monocot bulbous taxa.

The mucilaginous testa is often mistaken for an aril; the turgor pressure that builds up there forces the rest of the seed out explosively, rather like squeezing a grape pip.

Economic Importance. For Oxalis tuberosa (oca) and its relatives, see Emswhiller (2002).

Chemistry, Morphology, etc. Averrhoa is rather different from other members of the family. It has sieve tube plastids with protein crystalloids + fibers and starch, the ovules are weakly but definitely crassinucellate and there is an endothelium (Boesewinkel 1985b; Chung & Lim 1998). The leaves of Averrhoa carambola are two-ranked.

The pollen of Oxalidaceae often contains starch. Link (1992a) describes the nectary glands as being opposite the calyx, but they are opposite the corolla at the bases of the filaments (e.g. Rama Devi 1991). Some information is taken from Narayana (1970: embryology, etc.), Robertson (1975: general) and Cocucci (2004: general); for cork position, see Averrhoa bilimbi.

Phylogeny. For relationships within some southern African Oxalis speies, see Oberlander et al. (2004).

Classification. The family is circumscribed more narrowly than in Cronquist (1981); Hypseocharis is placed in Geraniaceae; Lepidobotryaceae (Celastrales) and Dirachmaceae (Rosales) are separate families. See Lourteig (2000, and references) for extensive monographic work on Oxalis.

Synonymy: Averrhoaceae Hutchinson.

Cunoniaceae [Elaeocarpaceae [Brunelliaceae + Cephalotaceae]]: K valvate, postgenitally coherent by hairs; (antepetalous A shorter than the others).

CUNONIACEAE R. Brown, nom. cons.   Back to Oxalidales

Woody, branching from the current flush; plants often Al-accumulators; ellagic acid + or 0 [Bauera, Eucryphia]; wood with crystals; vessel elements with (simple to) mixed or scalariform perforation plates; sieve tubes with non-dispersive protein bodies; young stem with vascular cylinder; (nodes 1:3 [Bauera], 5:5; split laterals; etc.); petiole bundles (arcuate) annular (adaxial or medullary bundles +); stomata variable; leaves opposite, (palmate, simple), 2ndaries proceeding to the teeth, or not, (stipels +), margins gland-toothed, stipule interpetiolar, rounded (acicular; 2, cauline-intrapetiolar - Lamanonia; 1, intrapetiolar), colleters +; flowers rather small, (4-)5(-10)-merous; C (0), ± = K in size (large), A 2 x K(-many, centripetal, with trunk bundles; = and opposite sepals [C - Spiraeanthemum]; obdiplostemonous), filaments (not articulated), often longer than the petals, incurved in bud, pollen dicolpate, nectary +, G (?1 - Hooglandia)[2 (3-)5(-many)] (free; inferior), opposite petals [?always], placentae intruding, (1) 2-several epitropous (apotropous) ovules/carpel, micropyle various, inc. zig-zag, obturator +, (style hollow), stigmas punctate to capitate or decurrent; fruit a septicidal capsule, or follicle (drupe); exotestal and endotegmic cells tangentially elongated; endosperm (0), starchy (not Davidsonia); n = (12, 14-)16.

27[list]/280: Weinmannia (160), Pancheria (26). Largely temperate and tropical S. hemisphere, few African (Map: from Good 1974). [Photo - Flower, Flower.]

• Cunoniaceae may be recognised by their opposite, usually odd-pinnately compound leaves with serrate leaflets and well-developed often intrapetiolar stipules. The flowers are often quite small and the filaments are notably longer than the petals. The fruit, when a capsule, is septicidal.

Evolution. Fossil flowers of Platydiscus peltatus from the Late Cretaceous of Sweden ca 85 million years ago seem assignable to this family (Schönenberger et al. 2001a).

Chemistry, Morphology, etc. Several genera are distinctive. These include Davidsonia, which has myricetin, hairs urticating hair, spiral leaves with two large, lateral stipules. The small flowers lack petals, and the stamens, twice the number of sepals, alternate with nectariferous lobes. The gynoecium is bicarpellate and the placentation apical-axile with 5-7 pendulous ovules/carpel. The fruit is a schizocarpic drupe, the endocarp producing the "hairs". The 1-2 seeds are pachychalazal, vascularised, and lack endosperm. Eucryphia has flowers that have large petals, many stamens and 2-colpate pollen grains. The gynoecium has four-many carpels, and in fruit the carpels (valves) more or less separate and open internally; there is no coherent columella. Hooglandia has small stipules; the plant is dioecious, and the flowers lack a corolla and apparently have only a single carpel with two ovules; the fruit is a single-seeded drupe.

There are numerous lignified cells in the bark of Cunoniaceae. That Bauera has 1:3 nodes may be connected with the fact that it sometimes lacks stipules, however, there is considerable vegetative variation in the genus: When the leaves are trifoliate, there are no stipules; when the leaves are simple, the stipules are foliaceous. Both Eucryphia and Cunoniaceae s. str. have very small sieve tube plastids, those of the former have protein inclusions only and are about the smallest known (Behnke 1988b). The leaf teeth have a glandular apex: the lower branch of the main vein goes into the tooth, the other proceeds above it. Nodal anatomy is variable, as is stipule development; single interpetiolar stipules may be paired as primordia (Rutishauser & Dickison 1989). The flowers in an inflorescence often open almost simultaneously (Bradford & Barnes 2001) and sometimes centrifugally. The nectary varies in position from extrastaminal to intrastaminal. The pollen grains are typically very small. Cunonia has two oblique carpels (Engler 1930b). There are often five traces to each carpel. The endosperm is described as being oily by Cronquist (1981) and Mabberley (1997), but starchy by Hopkins and Hoogland (2002) and Bradford et al. (2004). It is not clear how common pachychalazal seeds are (see Doweld 1998a).

See also Jay (1968b) for chemistry, Dickison (1980a) for wood anatomy, Dickison (1980b) and Rutishauser and Dickison (1989) for nodal anatomy, Rutishauser and Dickison (1989) and Dickison and Rutishauser (1990) for stipules, Hufford and Dickison (1992) for morphology, Gregory (1998) for general anatomy, Mathews et al. (2001) and Schönenberger et al. (2001a) for some floral morphology; Dickison (1989b) and Bradford et al. (2004) provide general information

Phylogeny. Morgan and Soltis (1993) early associated Baueraceae and Cunoniaceae. Note that morphological phylogenetic analyses of Cunoniaceae in the old sense, i.e. including Aphanopetalum (now Saxifragales), do not signal the latter out as being anything particularly distinctive... (Hufford & Dickinson 1992; Orozco Pardo 2002). Acsmithia + Spiraeanthemum form a clade sister to the rest of the family (Bradford & Barnes 2001). They have follicular fruits and vessel elements with scalariform perforation plates, but both features occur elsewhere in the family. Bradford (2002) discusses evolution in Cunonieae, while Sweeney et al. (2004) placed the distinctive and recently-discovered Hooglandia firmly in the family.

Synonymy: Baueraceae Lindley, Belangeraceae J. Agardh, Callicomaceae J. Agardh, Davidsoniaceae Bange, Eucryphiaceae Endlicher, nom. cons., Spiraeanthemaceae Doweld

Elaeocarpaceae [Brunelliaceae + Cephalotaceae] : inner integument 3-5 cells across.

ELAEOCARPACEAE Candolle, nom. cons.   Back to Oxalidales

Trees or (ericoid) shrublets; pyrrolizidine and tropane alkaloids, etc., ellagic acid +; vessel elements in radial multiples and with simple (scalariform) perforations; (nodes 1:1); petiole bundle annular, often with medullary (and flange) bundles; stomata anomo- para- or cyclocytic; leaves spiral or opposite (two-ranked), simple, ptyxis variable, margins toothed (entire), 2ndary veins pinnate or palmate, stipules lateral (0; colleters +); inflorescence racemose or cymose or flowers axillary; pedicels articulated (0), flowers pendant, (4-merous), K (4-9), (connate), C (3-6; cochlear, etc.), fringed (0), with three traces, large nectariferous disc/androgynophore (0), A (1)2 x K-many, centrifugal (± in groups opposite sepals), basifixed, filaments short, anthers tubular-porose or with short slits, (connective prolonged), with lignified hairs, G (1) [2-many], 1-many (apical, pendulous, epitropous) ovules/carpel, ovules ± hairy, with curved chalazal appendage, outer integument 4-6 cells across, inner integument 6-12 cells across, (micropyle zig-zag), style +, stigma ± punctate; fruit a (loculicidal + septicidal) capsule, spiny or not, or drupe (berry); when capsules, seeds hairy, with chalazal, raphal or integumentary aril, or apical chalazal strophiole, or not, testal cells ± elongated, thickened and lignified (sarcotesta +; endotesta not crystalliferous), tegmen with vascular bundles (endotegmen lignified); endosperm ± copious, oily, initially starchy [Tremandra, etc.], embryo green [1 record], (curved - Sericolea, some Elaeocarpus); n = 12, 14, 15, 21.

12[list]/605: Elaeocarpus (350), Sloanea (150), Tetratheca (50). Tropical, esp. Papuasia-Australia, not mainland Africa (Map: from Vester 1940; van Balgooy 1993). [Photo - Flower, Fruit.]

• Elaeocarpaceae are woody plants that can be recognised by their leaves that tend to turn red or orange red, sometimes yellow, as they die; the blades are often serrate and the petiole can be swollen at one or both ends. Terminalia branching is quite common. The moderate-sized, pendulous flowers are borne in often racemose inflorescences. Both calyx and corolla are often valvate, the petals, when present, are often fringed, there is often a very prominent disc that is usually outside the stamens, the basifixed anthers often have rather short filaments and dehisce by pores or short slits (these may elongate), and the fruit is either a drupe or berry or an often muricate capsule with arillate and/or hairy seeds.

Evolution. Stem group Elaeocarpaceae may be in the order of 66-64 million years old, whereas divergence of crown group members occured 59-57 million years before present (Wikström et al. 2001). Crayn et al. (2006) suggest diversification within the family may have been underway over 100 million years before present, with divergence of the xeromorphic Tremandra et al. clade occuring some 64 million years before present, and diversification beginning some 37 million years before present. Although there seems to have been elevated molecular divergence in the Tremandra et al. clade, it is distinctly less speciose than its sister clade, which includes Elaeocarpus, by far the lagest genus in the family (Crayn et al. 2006).

Chemistry, Morphology, etc. The corolla is more or less (induplicate-)valvate, at least near its insertion, each petal enclosing a group of stamens, and the corolla is larger than the calyx in advanced bud (it is usually smaller in rosids). Lignified cells are found in the insides of the ovary loculi. These and many other similarities strongly link the old Tremandraceae and Elaeocarpaceae (Matthews & Endress 2002a), although some, like basifixed anthers, may be connected with buzz pollination.

Leaf teeth have a single vein running to an opaque (non)glandular deciduous apex. Juvenile leaves of Sloanea may be pinnate. The petals may vary considerably in width within the same flower; in some species they are connate. The androecium is extremely variable, although sometimes when there are many stamens they are clearly fasciculate. Some Elaeocarpus have curved embryos. All in all, and even aside from the inclusion of Tremandraceae, Elaeocarpaceae are variable. Tremandraceae are ericoid shrublets with unilacunar nodes and lacking stipules (again the correlation); the pedicels are not articulated. The flowers are solitary, axillary, the corolla is induplicate-valvate and entire, disc [Tremandra] +, there are twice as many stamens as petals, and in Tetratheca these stamens are enveloped in pairs by the petals; the anthers are porose, with a long tube or not; the gynoecium is two-carpelllate and flattened with 1-2 apical pendulous epitropous ovules/carpel in a single row; and the inner integument is up to 25 cells across. The seed has a chalazal aril.

Information on wood anatomy is taken from Gasson (1996), and that on seed anatomy, etc., of Tremandraceae from Boeswinkel (1999 - he notes that it is very similar to that of Linaceae). See Coode (2004) for a general account of the expanded family.

Phylogeny. In Bradford and Barnes (2001) monophyly of Elaeocarpaceae is not established, but sampling in that part of Oxalidales was poor. However, monophyly is strongly supported in the more detailed analysis of Crayn et al. (2006: 88% bootstrap, 99% posterior probability). There the well-supported clade [Sloanea [Vallea + Aristotelia]] was sister to the rest of the family, [Crinodendron + Peripentadenia] and Dubouzetia perhaps being successively sister to the remainder of the family, where taxa from three genera of the old Tremandraceae were strongly supported as sister to a clade made up of Sericolea, Aceratium and Elaeocarpus which itself had little internal support and showed rather uneasy mixing...

Previous Relationships. Elaeocarpaceae were previously usually placed either in (Cronquist 1981) or adjacent to (Takhtajan 1997) Malvales, but there are numerous differences (e.g. absence of mucilage, indumentum type). Tremandraceae have long been of very uncertain position, for example, they were placed in Rosidae-Vochysiales (Takhtajan 1997) or Pittosporales (Cronquist 1981).

Synonymy: Aristoteliaceae Dumortier, Tetrathecaceae R. Brown, Tremandraceae Candolle, nom. cons.

Brunelliaceae + Cephalotaceae: inflorescence cymose; P uniseriate, G free, 2 basal ovules/carpel, styles recurved, stigma decurrent; fruit a follicle.

Chemistry, Morphology, etc. An odd couple, but Cephalotaceae will make strange bed-fellows wherever they go; see also Matthews and Endress (2006b) for characters linking the two.

BRUNELLIACEAE Engler, nom. cons.   Back to Oxalidales

Woody; chemistry?; cork?; vessel elements with simple and scalariform perforations; (nodes 5:5); petiole bundles annular or D-shaped, adaxial flange bundles +/0; stomata actinocyclic (anomocytic); hairs unicellular; leaves opposite, leaflets conduplicate, stipellate, 2ndaries prominent, proceeding to the (doubly toothed) margin, stipules cauline; breeding system various; flowers small, 4-8-merous, A 2(-3)x P, obdiplostemonous, pollen reticulate(-rugulate) to punctate, pistillodes in staminate flowers and staminodes in carpellate flower, disc +, G 2-8, carpels also alternating with C, ovules epitropous, inner integument ca 4 cells across, obturator +; endocarp separating from the rest in fruit, K persistent; seeds shiny, raphe ± aril-like, coat with subepidermal sclerenchymatous layer and palisade innermost layer; endosperm mealy; n = 14.

1[list]/55. Central and South America and the Antilles; more or less montane (Map: from Cuatrecasas 1970; note that Orozco Pardo 2002 does not include the easterly locations in South America). [Photo - Flower, Fruit.]

• Brunelliaceae may be recognised by their dense brown indumentum, their robust, rather flattened twigs, their opposite, usually odd-pinnately compound leaves with strongly serrate stipellate leaflets, and their rather small, paired cauline stipules (cf. Cunoniaceae!). The flowers are apetalous and have separate carpels and long-decurrent stigmas, and the fruits consist of groups of spreading and hairy follicles containing one or two shiny seeds that have an red, aril-like raphe down one side.

Chemistry, Morphology, etc. The nodes are described as being unilacunar (Orozco Pardo 2002; Orozco & Coba 2002), but there is some confusion here, and some nodes illustrated by Orozco Pardo (2002) certainly do not look unilacunar. The inner androecial whorl may have twice as many stamens as perianth members; the ovules are epitropous, unlike those of most Cunoniaceae. Pollen morphology is uninformative (Orozco 2001b). There are often five traces to each carpel. Orozco Pardo (2002) described the seeds as being arillate.

For general information, see Cuatrecasas (1970, 1985), Orozco Pardo (2002) and Kubitzki (2004b), for anatomy, Gregory (1998) and Orozco and Coba (2002), and for seed coat (which needs more study), Naranho and Huber (1971) and Danilova (1996).

Phylogeny. Orozco Pardo (2002) provides a morphology-based species level phylogeny of Brunelliaceae, together with comments on the biogeography of the genus.

CEPHALOTACEAE Dumortier, nom. cons.   Back to Oxalidales

Insectivorous herbs; flavanols and ellagic acid +, tannin 0; cork?; vessel elements with ?scalariform perforations; true tracheids +; young stem with vascular cylinder; nodes ?1:1; petiole bundles annular; stomata anomocytic; leaves spiral, ascidiate or not, margins entire, stipules 0; inflorescence scapose, racemose, branches scorpioid cymes; flowers 6-merous, hypanthium broad, P cucullate, disc with glandular projections, esp. alternating with P, connective with a glandular tip, G 6, carpels plicate, loculi filled with secretions, 1(2) ?type ovules/carpel, micropyle endostomal, inner integument 3-5 cells across; hypanthium accrescent in fruit; seed coat collapsed; endosperm development?, embryo short; n = 10.

1[list]/1: Cephalotus follicularis. S.W. Australia (Map: from Vester 1940). [Photo - Habit, Plant © H. Schneider.]

• Cephalotacaceae are insectivorous herbs that may be recognised by their rosette of leaves, some of which are fluted pitchers with lids (the leaves are reported to look like "vegetable hedgehogs" when young!), and scapose inflorescences with cymose branches. The six-merous flowers are small, lack petals, and have free carpels.

Evolution. There are nectar glands in the mouth of the pitcher which may faciltate the capture of insects (Bauer et al. 2008).

Chemistry, Morphology, etc. Some information is taken from Diels (1930a), Jay and Lebreton (1973), Danilova (1996), Gregory (1998: anatomy), Conran (2004: general) and the Carnivorous Plants Database; see also MacFarlane (1911), Lloyd (1942) and Juniper et al. (1989).

Chemistry, Morphology, etc. Cephalotaceae were included in a heterogeneous Rosales by Cronquist (1981) where they were surrounded by families now included in Saxifragales; Cephalotales immediately followed Saxifragales in the system of Takhtajan (1997).