EMBRYOPSIDA Pirani & Prado
Gametophyte dominant, independent, multicellular, not motile, initially ±globular; showing gravitropism; acquisition of phenylalanine lysase [PAL], microbial terpene synthase-like genes +, triterpenoids produced by CYP716 enzymes, phenylpropanoid metabolism [lignans +, flavonoids + (absorbtion of UV radiation)], xyloglucans in primary cell wall, side chains charged; plant poikilohydrous [protoplasm dessication tolerant], ectohydrous [free water outside plant physiologically important]; thalloid, leafy, with single-celled apical meristem, tissues little differentiated, rhizoids +, unicellular; chloroplasts several per cell, pyrenoids 0; glycolate metabolism in leaf peroxisomes [glyoxysomes]; centrioles/centrosomes in vegetative cells 0, microtubules with γ-tubulin along their lengths [?here], interphase microtubules form hoop-like system; metaphase spindle anastral, predictive preprophase band + [with microtubules and F-actin; where new cell wall will form], phragmoplast + [cell wall deposition centrifugal, from around the anaphase spindle], plasmodesmata +; antheridia and archegonia jacketed, surficial; blepharoplast +, centrioles develop de novo, bicentriole pair coaxial, separate at midpoint, centrioles rotate, associated with basal bodies of cilia, multilayered structure + [4 layers: L1, L4, tubules; L2, L3, short vertical lamellae] (0), spline + [tubules from L1 encircling spermatid], basal body 200-250 nm long, associated with amorphous electron-dense material, microtubules in basal end lacking symmetry, stellate array of filaments in transition zone extended, axonemal cap 0 [microtubules disorganized at apex of cilium]; male gametes [spermatozoids] with a left-handed coil, cilia 2, lateral; oogamy; sporophyte multicellular, cuticle +, plane of first cell division transverse [with respect to long axis of archegonium/embryo sac], sporangium and upper part of seta developing from epibasal cell [towards the archegonial neck, exoscopic], with at least transient apical cell [?level], initially surrounded by and dependent on gametophyte, placental transfer cells +, in both sporophyte and gametophyte, wall ingrowths develop early; suspensor/foot +, cells at foot tip somewhat haustorial; sporangium +, single, terminal, dehiscence longitudinal; meiosis sporic, monoplastidic, MTOC [MTOC = microtubule organizing centre] associated with plastid, sporocytes 4-lobed, cytokinesis simultaneous, preceding nuclear division, quadripolar microtubule system +; wall development both centripetal and centrifugal, sporopollenin + laid down in association with trilamellar layers [white-line centred lamellae; tripartite lamellae], >1000 spores/sporangium; nuclear genome size <1.4 pg, main telomere sequence motif TTTAGGG, LEAFY and KNOX1 and KNOX2 genes present, ethylene involved in cell elongation; chloroplast genome with close association between trnLUAA and trnFGAA genes [precursors for starch synthesis], tufA gene moved to nucleus.
Many of the bolded characters in the characterization above are apomorphies of subsets of streptophytes along the lineage leading to the embryophytes, not apomorphies of crown-group embryophytes per se.
All groups below are crown groups, nearly all are extant. Characters mentioned are those of the immediate common ancestor of the group,  contains explanatory material, () features common in clade, exact status unclear.
Abscisic acid, L- and D-methionine distinguished metabolically; pro- and metaphase spindles acentric; sporophyte with polar transport of auxins, class 1 KNOX genes expressed in sporangium alone; sporangium wall 4≤ cells across [≡ eusporangium], tapetum +, secreting sporopollenin, which obscures outer white-line centred lamellae, columella +, developing from endothecial cells; stomata +, on sporangium, anomocytic, cell lineage that produces them with symmetric divisions [perigenous]; underlying similarities in the development of conducting tissue and of rhizoids/root hairs; spores trilete; shoot meristem patterning gene families expressed; MIKC, MI*K*C* genes, post-transcriptional editing of chloroplast genes; gain of three group II mitochondrial introns, mitochondrial trnS(gcu) and trnN(guu) genes 0.
[Anthocerophyta + Polysporangiophyta]: gametophyte leafless; archegonia embedded/sunken [only neck protruding]; sporophyte long-lived, chlorophyllous; cell walls with xylans.
Sporophyte well developed, branched, branching apical, dichotomous, potentially indeterminate; hydroids +; stomata on stem; sporangia several, terminal; spore walls not multilamellate [?here].
Vascular tissue + [tracheids, walls with bars of secondary thickening].
EXTANT TRACHEOPHYTA / VASCULAR PLANTS
Sporophyte with photosynthetic red light response, stomata open in response to blue light; plant homoiohydrous [water content of protoplasm relatively stable]; control of leaf hydration passive; plant endohydrous [physiologically important free water inside plant]; (condensed or nonhydrolyzable tannins/proanthocyanidins +); xyloglucans with side chains uncharged [?level], in secondary walls of vascular and mechanical tissue; lignins +; stem apex multicellular, with cytohistochemical zonation, plasmodesmata formation based on cell lineage; tracheids +, in both protoxylem and metaxylem, G- and S-types; sieve cells + [nucleus degenerating]; endodermis +; leaves/sporophylls spirally arranged, blades with mean venation density ca 1.8 mm/mm2 [to 5 mm/mm2], all epidermal cells with chloroplasts; sporangia adaxial, columella 0; tapetum glandular; ?position of transfer cells; MTOCs not associated with plastids, basal body 350-550 nm long, stellate array in transition region initially joining microtubule triplets; suspensor +, shoot apex developing away from micropyle/archegonial neck [from hypobasal cell, endoscopic], root lateral with respect to the longitudinal axis of the embryo [plant homorhizic].[MONILOPHYTA + LIGNOPHYTA]
Sporophyte endomycorrhizal [with Glomeromycota]; growth ± monopodial, branching spiral; roots +, endogenous, positively geotropic, root hairs and root cap +, protoxylem exarch, lateral roots +, endogenous; G-type tracheids +, with scalariform-bordered pits; leaves with apical/marginal growth, venation development basipetal, growth determinate; sporangium dehiscence by a single longitudinal slit; cells polyplastidic, MTOCs diffuse, perinuclear, migratory; blepharoplasts +, paired, with electron-dense material, centrioles on periphery, male gametes multiciliate; chloroplast long single copy ca 30kb inversion [from psbM to ycf2]; mitochondrion with loss of 4 genes, absence of numerous group II introns; LITTLE ZIPPER proteins.
Sporophyte woody; stem branching lateral, meristems axillary; lateral root origin from the pericycle; cork cambium + [producing cork abaxially], vascular cambium bifacial [producing phloem abaxially and xylem adaxially].
Plants heterosporous; megasporangium surrounded by cupule [i.e. = unitegmic ovule, cupule = integument]; pollen lands on ovule; megaspore germination endosporic [female gametophyte initially retained on the plant].
EXTANT SEED PLANTS / SPERMATOPHYTA
Plant evergreen; nicotinic acid metabolised to trigonelline, (cyanogenesis via tyrosine pathway); microbial terpene synthase-like genes 0; primary cell walls rich in xyloglucans and/or glucomannans, 25-30% pectin [Type I walls]; lignin chains started by monolignol dimerization [resinols common], particularly with guaiacyl and p-hydroxyphenyl [G + H] units [sinapyl units uncommon, no Maüle reaction]; root stele diarch to pentarch, xylem and phloem originating on alternating radii, cork cambium deep seated; stem apical meristem complex [with quiescent centre, etc.], plasmodesma density in SAM 1.6-6.2[mean]/μm2 [interface-specific plasmodesmatal network]; eustele +, protoxylem endarch, endodermis 0; wood homoxylous, tracheids and rays alone, tracheid/tracheid pits circular, bordered; mature sieve tube/cell lacking functioning nucleus, sieve tube plastids with starch grains; phloem fibres +; cork cambium superficial; leaf nodes 1:1, a single trace leaving the vascular sympodium; leaf vascular bundles amphicribral; guard cells the only epidermal cells with chloroplasts, stomatal pore with active opening in response to leaf hydration, control by abscisic acid, metabolic regulation of water use efficiency, etc.; axillary buds +, exogenous; prophylls two, lateral; leaves with petiole and lamina, development basipetal, lamina simple; sporangia borne on sporophylls; spores not dormant; microsporophylls aggregated in indeterminate cones/strobili; grains monosulcate, aperture in ana- position [distal], primexine + [involved in exine pattern formation with deposition of sporopollenin from tapetum there], exine and intine homogeneous, exine alveolar/honeycomb; ovules with parietal tissue [= crassinucellate], megaspore tetrad linear, functional megaspore single, chalazal, sporopollenin 0; gametophyte ± wholly dependent on sporophyte, development initially endosporic [apical cell 0, rhizoids 0, etc.]; male gametophyte with tube developing from distal end of grain, male gametes two, developing after pollination, with cell walls; female gametophyte initially syncytial, walls then surrounding individual nuclei; embryo cellular ab initio, suspensor short-minute, embryonic axis straight [shoot and root at opposite ends; plant allorhizic], cotyledons 2; embryo ± dormant; chloroplast ycf2 gene in inverted repeat, trans splicing of five mitochondrial group II introns, rpl6 gene absent; whole nuclear genome duplication [ζ - zeta - duplication], two copies of LEAFY gene, PHY gene duplications [three - [BP [A/N + C/O]] - copies], 5.8S and 5S rDNA in separate clusters.
ANGIOSPERMAE / MAGNOLIOPHYTA
Lignans, O-methyl flavonols, dihydroflavonols, triterpenoid oleanane, apigenin and/or luteolin scattered, [cyanogenesis in ANA grade?], lignin also with syringyl units common [G + S lignin, positive Maüle reaction - syringyl:guaiacyl ratio more than 2-2.5:1], hemicelluloses as xyloglucans; root cap meristem closed (open); pith relatively inconspicuous, lateral roots initiated immediately to the side of [when diarch] or opposite xylem poles; origin of epidermis with no clear pattern [probably from inner layer of root cap], trichoblasts [differentiated root hair-forming cells] 0, hypodermis suberised and with Casparian strip [= exodermis]; shoot apex with tunica-corpus construction, tunica 2-layered; 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, not occluding pores of plate, companion cell and sieve tube from same mother cell; ?phloem loading/sugar transport; nodes 1:?; dark reversal Pfr → Pr; protoplasm dessication tolerant [plant poikilohydric]; stomata brachyparacytic [ends of subsidiary cells level with ends of pore], outer stomatal ledges producing vestibule, reduction in stomatal conductance with increasing CO2 concentration; lamina formed from the primordial leaf apex, margins toothed, development of venation acropetal, overall growth ± diffuse, secondary veins pinnate, fine venation hierarchical-reticulate, (1.7-)4.1(-5.7) mm/mm2, vein endings free; flowers perfect, pedicellate, ± haplomorphic, protogynous; parts free, numbers variable, development centripetal; P +, ?insertion, members each with a single trace, outer members not sharply differentiated from the others, not enclosing the floral bud; A many, filament not sharply distinguished from anther, stout, broad, with a single trace, anther introrse, tetrasporangiate, sporangia in two groups of two [dithecal], each theca dehiscing longitudinally by a common slit, ± embedded in the filament, walls with at least outer secondary parietal cells dividing, endothecium +, cells elongated at right angles to long axis of anther; tapetal cells binucleate; microspore mother cells in a block, microsporogenesis successive, walls developing by centripetal furrowing; pollen subspherical, tectum continuous or microperforate, ektexine columellate, endexine lamellate only in the apertural regions, thin, compact, intine in apertural areas thick, pollenkitt +; nectary 0; carpels present, superior, free, several, ascidiate [postgenital occlusion by secretion], stylulus at most short [shorter than ovary], hollow, cavity not lined by distinct epidermal layer, stigma ± decurrent, carinal, dry; suprastylar extragynoecial compitum +; 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, nucellar cap?; megasporocyte single, hypodermal, functional megaspore lacking cuticle; female gametophyte lacking chlorophyll, not photosynthesising, four-celled [one module, nucleus of egg cell sister to one of the polar nuclei]; ovule not increasing in size between pollination and fertilization; pollen grains land on stigma, bicellular at dispersal, mature male gametophyte tricellular, germinating in less than 3 hours, pollen tube elongated, unbranched, growing between cells, growth rate (20-)80-20,000 µm/hour, apex of pectins, wall with callose, lumen with callose plugs, penetration of ovules via micropyle [porogamous], whole process takes ca 18 hours, distance to first ovule 1.1-2.1 mm; male gametes lacking cell walls, ciliae 0, siphonogamy; double fertilization +, ovules aborting unless fertilized; P deciduous in fruit; mature seed much larger than fertilized ovule, small , dry [no sarcotesta], exotestal; endosperm +, cellular, development heteropolar [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 short [<¼ length of seed]; plastid and mitochondrial transmission maternal; Arabidopsis-type telomeres [(TTTAGGG)n]; nuclear genome very small [1C = <1.4 pg, mean 1C = 18.1 pg, 1 pg = 109 base pairs], whole nuclear genome duplication [ε/epsilon event]; 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, palaeo AP3 and PI genes [paralogous B-class genes] +, with "DEAER" motif, SEP3/LOFSEP and three copies of the PHY gene, [PHYB [PHYA + PHYC]]; chloroplast chlB, -L, -N, trnP-GGG genes 0.
[NYMPHAEALES [AUSTROBAILEYALES [[CHLORANTHALES + MAGNOLIIDS] [MONOCOTS [CERATOPHYLLALES + EUDICOTS]]]]]: wood fibres +; axial parenchyma diffuse or diffuse-in-aggregates; pollen monosulcate [anasulcate], tectum reticulate-perforate [here?]; ?genome duplication; "DEAER" motif in AP3 and PI genes lost, gaps in these genes.
[AUSTROBAILEYALES [[CHLORANTHALES + MAGNOLIIDS] [MONOCOTS [CERATOPHYLLALES + EUDICOTS]]]]: phloem loading passive, via symplast, plasmodesmata numerous; vessel elements with scalariform perforation plates in primary xylem; essential oils in specialized cells [lamina and P ± pellucid-punctate]; tension wood + [reaction wood: with gelatinous fibres, G-fibres, on adaxial side of branch/stem junction]; tectum reticulate; anther wall with outer secondary parietal cell layer dividing; nucellar cap + [character lost where in eudicots?]; 12BP [4 amino acids] deletion in P1 gene.
[[CHLORANTHALES + MAGNOLIIDS] [MONOCOTS [CERATOPHYLLALES + EUDICOTS]]] / MESANGIOSPERMAE: benzylisoquinoline alkaloids +; sesquiterpene synthase subfamily a [TPS-a] [?level], polyacetate derived anthraquinones + [?level]; outer epidermal walls of root elongation zone with cellulose fibrils oriented transverse to root axis; P more or less whorled, 3-merous [?here]; pollen tube growth intra-gynoecial; extragynoecial compitum 0; carpels plicate [?here]; embryo sac bipolar, 8 nucleate, antipodal cells persisting; endosperm triploid.
[MONOCOTS [CERATOPHYLLALES + EUDICOTS]]: (extra-floral nectaries +); (veins in lamina often 7-17 mm/mm2 or more [mean for eudicots 8.0]); (stamens opposite [two whorls of] P); (pollen tube growth fast).
[CERATOPHYLLALES + EUDICOTS]: ethereal oils 0.
EUDICOTS: (Myricetin, delphinidin +), asarone 0 [unknown in some groups, + in some asterids]; root epidermis derived from root cap [?Buxaceae, etc.]; (vessel elements with simple perforation plates in primary xylem); nodes 3:3; stomata anomocytic; flowers (dimerous), cyclic; protandry common; K/outer P members with three traces, ("C" +, with a single trace); A ?, filaments fairly slender, anthers basifixed; microsporogenesis simultaneous, pollen tricolpate, apertures in pairs at six points of the young tetrad [Fischer's rule], cleavage centripetal, wall with endexine; G with complete postgenital fusion, stylulus/style solid [?here]; seed coat?
[PROTEALES [TROCHODENDRALES [BUXALES + CORE EUDICOTS]]]: (axial/receptacular nectary +).
[TROCHODENDRALES [BUXALES + CORE EUDICOTS]]: benzylisoquinoline alkaloids 0; euAP3 + TM6 genes [duplication of paleoAP3 gene: B class], mitochondrial rps2 gene lost.
[BUXALES + CORE EUDICOTS]: mitochondrial rps11 gene lost.
CORE EUDICOTS / GUNNERIDAE: (ellagic and gallic acids +); leaf margins serrate; compitum + [one position]; micropyle?; γ whole nuclear genome duplication [palaeohexaploidy, gamma triplication], PI-dB motif +, small deletion in the 18S ribosomal DNA common.
[ROSIDS ET AL. + ASTERIDS ET AL.] / PENTAPETALAE: root apical meristem closed; (cyanogenesis also via [iso]leucine, valine and phenylalanine pathways); flowers rather stereotyped: 5-merous, parts whorled; P = calyx + corolla, the calyx enclosing the flower in bud, sepals with three or more traces, petals with a single trace; stamens = 2x K/C, in two whorls, internal/adaxial to the corolla whorl, alternating, (numerous, but then usually fasciculate and/or centrifugal); pollen tricolporate; G , G  also common, when [G 2], carpels superposed, placentation axile, style +, stigma not decurrent; compitum +; endosperm nuclear; fruit dry, dehiscent, loculicidal [when a capsule]; RNase-based gametophytic incompatibility system present; floral nectaries with CRABSCLAW expression; (monosymmetric flowers with adaxial/dorsal CYC expression).
[BERBERIDOPSIDALES [SANTALALES [CARYOPHYLLALES + ASTERIDS]]] / ASTERIDS ET AL. / SUPERASTERIDS: ?
[SANTALALES [CARYOPHYLLALES + ASTERIDS]]: ?
[CARYOPHYLLALES + ASTERIDS]: seed exotestal; embryo long.
ASTERIDS / ASTERIDAE / ASTERANAE Takhtajan: nicotinic acid metabolised to its arabinosides; (iridoids +); tension wood decidedly uncommon; C enclosing A and G in bud, (connate [sometimes evident only early in development, petals then appearing to be free]); anthers dorsifixed?; if nectary +, gynoecial; G , style single, long; ovules unitegmic, integument thick, endothelium +, nucellar epidermis does not persist; exotestal [!: even when a single integument] cells lignified, esp. on anticlinal and/or inner periclinal walls; endosperm cellular.
[ERICALES [ASTERID I + ASTERID II]]: (ovules lacking parietal tissue) [tenuinucellate].
[ASTERID I + ASTERID II] / CORE ASTERIDS / EUASTERIDS: plants woody, evergreen; ellagic acid 0, non-hydrolysable tannins not common; vessel elements long, with scalariform perforation plates; nodes 3:3; sugar transport in phloem active; inflorescence usu. basically cymose; flowers rather small [<8 mm across]; C free or basally connate, valvate, petals often with median adaxial ridge and inflexed apex; A = and opposite sepals or P, (numerous [usu. associated with increased numbers of C or G]), free to basally adnate to C; G #?; ovules 2/carpel, apical, pendulous; fruit a drupe, drupe ± flattened, surface ornamented; seed single; duplication of the PI gene.
ASTERID II / CAMPANULIDAE:myricetin 0; style shorter than the ovary; endosperm copious, embryo short/very short.
[ASTERALES [ESCALLONIALES [BRUNIALES [APIALES [PARACRYPHIALES + DIPSACALES]]]]] / APIIDAE: iridoids +; C forming a distinct tube, tube initiation early; A epipetalous; ovary inferior, [2-3], style long[?].
[ESCALLONIALES [BRUNIALES [APIALES [PARACRYPHIALES + DIPSACALES]]]]: ?
[BRUNIALES [APIALES [PARACRYPHIALES + DIPSACALES]]]: ?
[APIALES [PARACRYPHIALES + DIPSACALES]] / DIPSAPIIDAE: nodes 3:3.
[PARACRYPHIALES + DIPSACALES] / DIPSIDAE: true tracheids +; lamina margin serrate; inflorescence terminal.
Age. K. Bremer et al. (2004) suggested an age of about 111 m.y. for this node, Magallón et al. (2015) an age of ca 81.8 m.y., and Wikström et al. (2015) an age of (104-)92(-79) m.y.; around 94.2 m.y. is the estimate in Tank et al. (2015: Table S2) and (101.4-)86.6(-71.8) m.y. in Tank and Olmstead (2017).
Evolution: Divergence & Distribution. Diversification at this node probably occurred in the southern hemisphere (Beaulieu et al. 2013a).
Dipsacales, with some 1130 species, are far more diverse than Paracryphiales - the latter include a mere 36 or so species.
PARACRYPHIALES Reveal Main Tree.
Vessel elements with highly scalariform perforation plates; nodes 3:3; inflorescence racemose; flowers 4-merous; P or K + C free; A not adnate to P/C, anther thecae ± embedded in connective/basifixed; G position?; capsule septicidal. - 1 family, 3 genera, 36 species.
Age. K. Bremer et al. (2004) suggested an age of about 101 m.y. for crown-group Paracryphiaceae/Paracryphiales; for more details, see below.
Note: Boldface denotes possible apomorphies, (....) denotes a feature common in the clade, exact status uncertain, [....] includes explanatory material. Note that the particular node to which many characters, particularly the more cryptic ones, should be assigned is unclear. This is partly because homoplasy is very common, in addition, basic information for all too many characters is very incomplete, frequently coming from taxa well embedded in the clade of interest and so making the position of any putative apomorphy uncertain. Then there are the not-so-trivial issues of how character states are delimited and ancestral states are reconstructed (see above).
Evolution: Divergence & Distribution. The three genera included in Paracryphiales are quite different florally and are also rather unlike other campanulids. Quintinia is reported to have ellagic acid (along with iridoids!), and it and fossils that have been associated with it may even have bitegmic ovules (Friis & Pedersen 2012). Sphenostemon and Paracryphia sometimes have more than twice as many stamens as perianth parts; the apomorphies of Paracryphia in particular represent a very odd combination for an euasterid. Altogether, something of a conundrum.
Chemistry, Morphology, etc. For more on the inferior/superior ovary distinction in the campanulids, see the Asterales page.
All three genera are poorly known - Sphenostemon particularly so - and need an exhaustive comparative study; this should be accompanied by a reworking of their molecular relationships.
Phylogeny. For the relationships of Paracryphiales, see the asterid II clade.
Synonymy: Sphenostemonineae I. Savin. - Quintiniales Doweld, Sphenostemonales Doweld
PARACRYPHIACEAE Airy-Shaw Back to Paracryphiales
Trees or shrubs, evergreen; leaves spiral, lamina margins serrate (entire); inflorescences terminal; fruit a septicidal capsule.
3 [list]/36. Southwest Pacific: Philippines to New Zealand and New Caledonia.
Age. K. Bremer et al. (2004) suggested an age of about 101 m.y. and Wikström et al. (2015) an age of (98-)78(-32) m.y. for crown-group Paracryphiaceae.
The Late Cretaceous Silvianthemum suecicum, from rocks in southern Sweden has several exquisitely-preserved features - perhaps most notably the radial stylar cells - suggesting a relationship with Quintinia in particular (Friis 1990). Martínez-Millán (2010: 83.5 m.y.o.) recovered this relationship in a phylogenetic analysis of possibly related campanulids, although no other Paracryphiales were included, and she thought better knowledge of Escalloniales might help place the fossil more securely (see also Friis et al. 2011, 2013b). However, Silvianthemum has tricolp(or)ate pollen, there are eight stamens (c.f. Friis et al. 2011: the perianth is 5-merous), the anthers appear to be dorsifixed (a synapomorphy with Quintinia - Martínez-Millán 2010), there are three short, adaxially grooved styles (c.f. Quintinia), and three stipitate parietal placentae. Bertilanthus scanicus, from the same rocks, has a very similar set of characters, and, like Quintinia, it has glandular hairs, but it also has stamens opposite the petals, a feature at most vanishingly infrequent in the campanulids, and differs in other respects from Quintinia (Friis & Pedersen 2012). However, the androecium in extant Paracryphiales is variable. The ovules of Bertilanthus may be bitegmic ("ovary wall [sic] split in two": Friis & Pedersen 2012: p. 326), which would be in line with reports for Quintinia.
If the relationships of these fossils hold, then the current distribution of Paracryphiales has little to do with their past distribution. However, a position of the fossils within Cornales was suggested by Beaulieu et al. (2013a), which agrees better with their morphology (and geography). Moreover, Friis et al. (2013b) are inclined to question the position of Quintinia itself in the campanulids.
1. Quintinia A. de Candolle
Plants Al accumulators, group 1 secoiridoids, ellagic acid +; pits vestured; (nodes 5:5); petiole bundle?; peltate glands + [cells of head radiating]; buds naked; inflorescences branched or not; flowers also 5-merous; K not protecting bud, sepals with 1 trace, aestivation open; pollen 4-6 colporate; G [3-5], inferior, placentation ± parietal, nectary on top of ovary, style longish, postgenitally connate, stout, with prominent radiating cells, stigmas expanded, wet; ovules 3-many/carpel, ?bitegmic, micropyle endostomal, parietal tissue absent; K persistent; micropylar endosperm haustorium?; n = ?22.
1/25. Philippines and New Guinea to New Zealand and New Caledonia (map: from Heywood 2007, in part).
Synonymy: Quintiniaceae Doweld
[Paracryphia + Sphenostemon]: styloids +; hairs unicellular; bud perulate; K/P decussate; nectary 0; style 0.
2. Paracryphia Baker f.
Chemistry?; petiole bundle flattened-annular, with medullary bundles; hairs dense; plant andromonoecious; inflorescence branched; flowers sessile; P (5), decussate-cochleate, caducous; A 8(-15); G [8-15], stigmas central, separate, conduplicate; ovules 4/carpel, integument ca 4 cells across, parietal tissue 1-2 cells across; carpels pulling away acropetally and opening adaxially, columella persistent; seeds winged, exotesta with sinuous anticlinal walls, inner walls lignified; embryo size?, radicle relatively long; n = ?
1/1: Paracryphia alticola. New Caledonia.
3. Sphenostemon Baillon
Iridoids?; phloem stratified; (styloids +); petiole bundles three, arcuate, or flattened horizontal C-shaped, or annular with wing bundles; leaves (opposite), stipules cauline, minute; inflorescences (axillary), unbranched; (P 2), decussate; stamens = and opposite P, -12 [when P 0], connective massive, filaments shorter than anthers; pollen 3-/4-por(or)ate (inaperturate); G , placentation apical, stigma large, capitate; ovules 1(2)/carpel, apotropous, "crassinucellate", endothelium?, funicular obturator +, funicle massive, obtuator papillate; fruit a berry; seeds ruminate or not, exo- or exoendotestal, endotestal cells with dark contents; embryo short?; n = ?
1/10. New Guinea, Australia (Queensland) and New Caledonia (map: from van Balgooy 1984; Mark Newman, pers. comm.).
Synonymy: Sphenostemonaceae P. van Royen
Evolution: Divergence & Distribution. The vessel elements of the three genera are very long and the perforation plates have many bars, indeed, aspects of the wood anatomy of Paracryphia have been considered to be among the most primitive in angiosperms.
Chemistry, Morphology, etc. The considerable variation in petiole anatomy in Sphenostemon may depend where in the petiole the transverse sections were taken. Styloids are visible on the abaxial surface of the lamina of Papuasian species of Sphenostemon; they look rather like cystoliths.
The placentation of Quintinia is basically parietal (Bensel & Palser 1975b; see also Friis et al. 2103b); the ovules may be bitegmic and crassinucellate (Mauritzon 1933; Philipson 1974; Friis et al. 2013b). For some details of the flower of Sphenostemon, see Endress (2008c). Its fruit is often described as being a drupe, but Lundberg (2001c) characterized it as being a pseudo-drupe (and the seeds as being pachychalazal), while Savinov (2003) described it as being a berry. The nature of the perianth in both Paracryphia and Sphenostemon needs attention. In the former, it is almost as if the bract encloses the sessile flower, while in the latter the first perianth members are lateral and subpeltate.
For Paracryphia, see also Dickison and Baas (1977) and Carlquist (2012c) for wood anatomy, and Swamy (1953b), Lundberg (2001e) and Dickison and Lunberg (2016), all general. For Quintinia, see Lundberg (2000d) and Dickison and Lunberg (2016), both general. For Sphenostemon, see Bailey and Swamy (1953), Jéremie (1997) and Thiv (2016) for general information, Carlquist (2012c) for wood anatomy, and Savinov (2003) for fruit and seed anatomy.
Phylogeny. Relationships are [Quintinia [Paracryphia + Sphenostemon]] (Tank & Donoghue 2009).
Classification. The three genera have all been placed in monogeneric families, but only relatively recently; they are combined here (see also A.P.G. 2009).
Thanks. Thanks to Y. Pillon for comments.
Previous Relationships. Just about everywhere. Paracryphiaceae were included in Theales by Cronquist (1981) and in Theanae by Takhtajan (1997). Quintinia has long been included in woody Saxifragaceae/Hydrangeaceae. Baas (1975) thought that Sphenostomonaceae (and Phellinaceae) were members of Celastrales, close to Icacinaceae; Cronquist (1981) had placed them in Aquifoliaceae, next to Icacinaceae, while Takhtajan (1997) included them in Icacinales. Sphenostemon (as Idenburgia) has also been placed in Trimeniaceae.