WOOD ANATOMY OF TREMANDRACEAE: PHYLOGENETIC AND ECOLOGICAL IMPLICATIONS

Stems of four species of the Australian family Tremandraceae furnished sufficient material for analysis of wood anatomy. Presence of simple perforation plates on vessel elements, occurrence of libriform fibers (some septate), tendency toward vasicentric parenchyma, presence of crystalliferous axial parenchyma strands, presence of crystals singly in ray cells, and occurrence of amorphous deposits in parenchyma are all features in which Tremandraceae resemble Pittosporaceae. Wood anatomy tends to support a “rosoid” rather than a sapindalean, rutalean, or polygalalean affinity for Tremandraceae, although wood is only a preliminary indicator. By the use of numerical indices as well as such indicators as helical thickening and presence of vascular tracheids, wood of Tremandraceae is shown to be highly xeromorphic. The genus Tremandra may represent a secondary entrant into wet forests of southwestern Australia; it clearly is not relict from mesic ancestry.     

Asteropeia and Physena (Caryophyllales): A case study in comparative wood anatomy

Previous analyses ofAsteropeia andPhysena have not compared the wood anatomy of these genera to those of Caryophyllales s.l. Molecular evidence shows that the two genera from a clade that is a sister group of the core Caryophyllales. Synapomorphies of theAsteropeia-Physena clade include small circular alternate pits on vessels, presence of vasicentric tracheids plus fiber-tracheids, presence of abaxial-confluent plus diffuse axial parenchyma, and presence of predominantly uniseriate rays. These features are analyzed with respect to habit and ecology of the two genera. Solitary vessels, present in both genera, are related to the presence of vasicentric tracheids. Autapomorphies in the two genera seem related to adaptations byPhysena as a shrub of moderately dry habitats (e.g., narrower vessel elements, abundant vasicentric tracheids, square to erect cells in rays) as compared to alternate character expressions that seem related to the arboreal habit and humid forest ecology ofAsteropeia. The functional significance of vasicentric tracheids and fiber-tracheids in dicotyledons is briefly reviewed in the light of wood anatomy of the two genera.     

Stem and root anatomical correlations with life form diversity, ecology, and systematics in Moringa (Moringaceae)

Four life forms (habits) are identified in the 13 species of Moringa (bottle trees, sarcorhizal trees, slender trees, and tuberous shrubs) which are examined for wood anatomical correlations with habit, ecology, and systematic. Wood anatomy is similar within habit classes except for the sarcorhizal trees. The four bottle tree species and M. arborea (one of the sarcorhizal trees) are characterized by bands of confluent paratracheal parenchyma alternating with bands of libriform fibres, some of which may be parenchyma-like. The other sarcorhizal tree, M. ruspoliana , is characterized by alternating bands of parenchyma-like and long, slender libriform fibres. Root secondary xylem of all these species is characterized by bands of parenchyma and fibres. Slender trees do not show bands of fibres of different shapes and have fibrous roots with less parenchyma than the other species. Tuberous shrubs have stems mostly composed of long, slender fibres and large underground tubers mostly composed of parenchyma. Quantitative trends between ecologically different localities include wider vessel elements and higher conductive area in moister localities. Wood anatomy provides characters that are of potential phylogenetic utility at a variety of levels of relationship. Based on wood anatomy and geography, the most likely sister taxon to Moringa is Cylicomorpha (Caricaceae).     

Wood anatomy of selected Cucurbitaceae and its relationship to habit and systematics

Qualitive and quantitative data are presented on wood anatomy and cambial conformations of four species of Cucurbitaceae. Although all woody to various degrees, the four species were selected to show a wide range of habits and therefore to discern possible correlations between habit and wood anatomy. Vessels are widely spaced and libriform fibers are minimal where storage of water and carbohydrates is prominent. Axial parenchyma is dimorphic: lignified thick-walled paratracheal may lend strength to the vessel elements (which are wider than long), whereas thin-walled apotracheal parenchyma may lend flexibility to stems (especially in lianoid species) and serve for storage. Rays are multiseriate only and alter little from primary rays (but large multiseriate rays originate suddently in fascicular areas of one species). Distribution and abundance of libriform fibers relate to habit: most abundant in the shrubby Acanthosicyos , least in the storage-oriented lower stems of Apondanthera ). Vasicentric tracheids extend radially and interconnect vessels, potentially providing a subsidiary conductive system that would maintain the conductive pathways of the large vessels if some of those vessels were to be disabled or deactivated. Cucurbitaceae are characterized by septate fibers, vasicentric tracheids, and storied wood structure. Each of these features is found in at least half of the families now commonly included in Violales, to which Cucurbitaceae are thought to belong.     

WOOD ANATOMY AND RELATIONSHIPS OF LACTORIDACEAE

Mature wood of Lactoris, not previously available for study, reveals ten distinctive characters: vessels with simple perforation plates; vessels in pore multiples; vessel-to-axial parenchyma pits scalariform or transitional, vessel-to-vessel pits alternate; fiber-tracheids with vestigial pits; fiber-tracheids, vessels, and axial parenchyma storied; axial parenchyma vasicentric scanty; axial parenchyma either not subdivided or, if subdivided, with thin nonlignified walls between the cells (like the septa in septate fibers); rays wide and tall, little altered during ontogeny; ray cells upright; and ray cells taller adjacent to fascicular areas. All of these features occur in woods of Piper and other Piperaceae. The systematic position of Lactoris is therefore reassessed. Evidence available to date is consonant with placement of Lactoridaceae in Piperales, in which it would be more primitive than Piperaceae or Saururaceae. Features cited as evidence for alternative placements of Lactoridaceae are reviewed.     

Wood anatomy of Gentianaceae, tribe Helieae, in relation to ecology, habit, systematics, and sample diameter

Twenty collections representing one species each ofSymbolanthus andTachia, and 17 species ofMacrocarpaea were studied by means of light microscopy and scanning electron microscopy (SEM). Wood details show that the three genera form a coherent group;Tachia differs from the others in only a few minor characters. Because the species studied form a natural group, wood variations within Helieae offer the basis for correlations and interpretations with respect to habit and ecology. Diameter of stems studied proves to be an important variable that must be taken into account. Correlations with stem diameter include wider vessels in outer wood of wider samples. This would correspond to deeper penetration of reliable water tables by roots of helioid trees or large shrubs. Ray height decreases with increase in stem diameter, an indication of paedomorphosis. Rays of all species are paedomorphic in histology by virtue of relative paucity or even absence of procumbent cells in multiseriate rays. Pseusoscalariform lateral wall pitting of vessels is also a feature characteristic of paedomorphosis. The assemblage of paedomorphic features correlates well with the conclusion, reached by authors who used cladistic methods, that Gentianaceae other than Gentianeae are derived from suffrutescent prennials. The Mesomorphy Ratio, which incorporates three vessel features, correlates with leaf length and with stem diameter. All Helieae are mesophytic, but to various degrees. Septate fiber-tracheids, where present, are typically near vessels and form a substitute for or an addendum to vasicentric axial parenchyma as a mechanism for photosynthate storage. Vestured pits occur on lateral wall pits of vessels of all Helieae, but not on the fibertracheids. Vestured pits show diversity withinMacrocarpaea, a feature of possible systematic significance.     

Pericarp anatomy and evolution inCoriaria (Coriariaceae)

The first overall study of pericarp anatomy ofCoriaria is presented to discuss its evolution and relationships within a genus. All 14 species investigated (including 11 narrowly defined species) have somewhat bilaterally flattened mature fruits with five to seven (or more) longitudinal costae. They share a usually nine-(or more-)cell-layered (at intercostal region), stratified mature pericarp, which is basically constructed by an exocarp, an outer, a middle and an inner zone of mesocarp, and an endocarp. While a multi-layered endocarp is composed of circumferentially elongate fibres, a multi-layered inner zone of the mesocarp comprises longitudinally elongate fibres. Despite its uncertain systematic value, the presence of those fibres arranged crisscross is a characteristic feature of the genus. Comparisons among species indicate thatCoriaria terminalis, a species of the Eastern Hemisphere, retains a basic or archaic, well-stratified pericarp structure similar to the one found in all the species investigated of the Southern and Western Hemisphere, and that four species of Asia,Coriaria napalensis, C. sinica, C. intermedia andC. japonica, share a specialized structure (lacking the outer zone of the mesocarp) indicative of their mutual close affinity. Comparisons further suggest distinctness ofCoriaria intermedia, as well as variously derived position ofC. myrtifolia andC. japonica.     

Wood anatomy of Krameriaceae with comparisons with Zygophyllaceae: phylesis, ecology and systematics

Wood of nine species of Krameria (including all clades proposed within the genus) reveals a few characters related to infrageneric systematics; most relate primarily to ecology and habit. Wood of Krameria closely fits quantitative data reported for desert shrubs. Lack of vessel grouping correlates with the presence of densely pitted tracheids. Wood xeromorphy in Krameria may relate in part to hemiparasitism. Tracheid presence may also account for relatively low vessel density. Wood anatomy of six species of Zygophyllaceae (including both genera of Morkillioideae) is compared with that of Krameriaceae because recent phylogenies propose that these two families comprise the order Zygophyllales. Several wood characters appear to represent synapomorphies reflecting this relationship. Differences in wood anatomy between Krameriaceae and Zygophyllaceae are believed to represent autapomorphies. Notable among these include Paedomorphic Type II rays (Krameriaceae), storying (Zygophyllaceae), presence of vestured pits (Zygophyllaceae), and differentiation into vasicentric tracheids and fibre-tracheids (Zygophyllaceae). The latter feature is referable to the concept of fibre-tracheid dimorphism. Recognition of Krameriaceae as separate from Zygophyllaceae is supported by wood characters. Wood of Zygophyllales does not conflict with the idea that the order belongs to rosids, with Malpighiaceae as the outgroup of Zygophyllales.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 257–270.     

Wood anatomy ofTrimeniaceae

Four collections of three species ofTrimenia and one collection ofPiptocalyx were studied; early-formed and later-formed wood was analyzed for oneTrimenia. Liquid-preserved material permitted analysis of mucilage and starch storage in wood ofT. neocaledonica andP. moorei. BecausePiptocalyx is scandent whereasTrimenia is arborescent, wood differences relative to evolution of a climbing habit could be examined.Piptocalyx contrasts withTrimenia in having wider vessels, more numerous per mm², resulting in a conductive area five times greater per unit area than that of theTrimenia woods averaged.Piptocalyx has appreciably fewer bars per perforation plate and thus much greater conductive area per perforation plate than have the species ofTrimenia. Rays inPiptocalyx are much taller and wider than those ofTrimenia. Wood ofTrimeniaceae is highly primitive in its scalariform perforation plates, scalariform lateral wall pitting on vessels, relatively long vessels elements, and heterocellular rays. Imperforate tracheary elements are septate nucleate fibertracheids (or even libriform fibers) rather than tracheids, but loss of borders on pits (and thus lowered conductive function of the imperforate tracheary elements) can be explained by the development of these elements into starchstoring cells. Some fiber-tracheids inT. neocaledonica are enlarged mucilagecontaining cells. Details of vessel structure inTrimeniaceae are similar to those ofMonimiaceae (s. s.), but similarity to some other lauralean (annonalean) families may be found: in mucilage presence,Trimeniaceae resembleLauraceae rather thanMonimiaceae. Wood ofTrimeniaceae may be regarded as highly mesomorphic, corresponding to the moist habitats in which all of the species occur.     

Wood anatomy of the endemic woody Asteraceae of St Helena I: phyletic and ecological aspects

Quantitative and qualitative data are given for samples of mature wood of all eight species of woody Asteraceae, representing three tribes, of St Helena I. The quantitative features of all except one species are clearly mesomorphic, corresponding to their mesic central ridge habitats. Commidendrum rugosum has more xeromorphic wood features and occurs in dry lowland sites. Commidendrum species are alike in their small vessel pits and abundant axial parenchyma. Melanodendrum agrees with Commidendrum in having fibre dimorphism and homogeneous type II rays. The short fibres in both genera are storied and transitional to axial parenchyma. Elongate crystals occur in ray cells of only two species of Commidendrum , suggesting that they are closely related. Wood of Commidendrum and Melanodendrum is similar to that of the shrubby genus Felicia , thought closely related to Commidendrum on molecular bases. Commidendrum and Melanodendrum have probably increased in woodiness on St Helena, but are derived from shrubby ancestors like today's species of Felicia. Petrobium wood is paedomorphic and indistinguishable from that of Bidens , from which Petrobium is likely derived. The two senecionid species (Senecio leucadendron = Pladaroxylon leucadendron; and Senecio redivivus = Lachanodes arborea , formerly Lachanodes prenanthiflord) also show paedomorphic wood. Wood of the various St Helena Asteraceae is consonant with relationship to African or South American ancestors that reached St Helena via long distance dispersal. Derivation from genera of Pacific islands or Austromalesian regions is considered less likely. However, DNA evidence is needed to clarify origins, times of colonization on St Helena and divergence from closest relatives, and the nature of evolutionary patterns.     

A new <Emphasis Type="Italic">Heteropterys</Emphasis> (Malpighiaceae) from semideciduous forest,with notes on wood anatomy

This paper describes and illustrates Heteropterys serrata, a new species endemic to semideciduous forests associated with inselbergs in the state of Espírito Santo, Brazil. Morphological and wood anatomical traits of the new species are compared to those of other species of the Heteropterys Metallophyllis informal group. Based on wood anatomy, H. serrata and H. nitida (the most morphologically similar species) have different axial parenchyma, which is scarce paratracheal in H. nitida (and some other species of the Metallophyllis informal group) and aliform confluent in H. serrata. The most notable morphological and anatomical characters that distinguish the new species are the young hexagonal stems, the unusual widely serrate leaf margins and the aliform confluent axial parenchyma in the wood.     

Anatomical wood variation of Buddleja cordata (Buddlejaceae) along its natural range in Mexico

Buddleja cordata is an evergreen species of wide distribution in Mexico that is represented by shrubs and trees. Wood variability of B. cordata was evaluated in relation to plant size as well as latitude, altitude, soils, and climatic data. Canonical correlation analysis (CCA) showed that two canonical correlations are significant (Wilks' λ, p<0.0001) and explained 76% of total variance. Redundancy analysis revealed that the first pair of canonical variates are significant, thus the canonical variate, named distribution, represents a gradient of maximum temperature of the warmest period, annual temperature range, and latitude in its area of distribution; whereas the canonical variate named wood represents vessel density, fiber length, and plant size, best associated to the environmental gradient. Vessel density expressed by its distribution in latewood and porosity type showed that ring-porosity is common in individuals from high latitudes. Temperatures below zero or lack of rainfall during several months might induce porosity variability in B. cordata as suggested by CCA, but was not related to phenology since the species is evergreen along its latitudinal range. Plant size was also influenced by extreme temperature and rainfall. Shorter plants are distributed in the northern population or driest sites located in north-central Mexico, and in addition, fiber length followed an allometric relation with individuals' height. Wood characters in B. cordata as for simple perforation plate, helical thickenings, type of intervascular and vessel-ray pits, scanty paratracheal parenchyma, and heterogeneous type IIB rays were not correlated with plant size, climate, and soil parameters or species distribution. These features are common with other species of Buddleja.An erratum to this article can be found at     

Anomalous secondary vascular tissue inHelminthostachys zeylanica (Ophioglossaceae)

The vascular anatomy ofHelminthostachys zeylanica was examined with special reference to anomalous secondary tissue. Primary xylem development gradually takes place centrifugally. In branched rhizomes with destroyed apices, the vascular cylinder apical to the insertion of branch traces is generally composed of primary xylem, accessory xylem, inner parenchyma of radially arranged cells, outer parenchyma of irregularly arranged cells, and partly crushed phloem, listed in order going outwards. The accessory xylem as well as the inner parenchyma ofHelminthostachys zeylanica is probably secondarily produced, partly to contribute to the branch traces, in a position corresponding to that of secondary vascular tissue developed from a normal cambium inBotrychium sensu lato. It is suggested that although a cambium is lacking inHelminthostachys zeylanica, the secondary vascular tissues are comparable between the genera. The phylogenetic implication of this tissue is discussed.     

Leaf anatomy ofDombeya andNesogordonia (Sterculiaceae), emphasizing epidermal and internal idioblasts

We studied leaf anatomy, using clearings, resin sections, and scanning electron microscopy, from mostly herbarium specimens of 123 species ofDombeya and 11 species ofNesogordonia (Sterculiaceae). Species were placed in seven idioblast categories, ranging from those without any to single and bicelled epidermal forms to multicelled nodules and single mesophyll idioblasts. Idioblast contents are possibly mucilaginous, but were not identified. In these two genera the range of foliar idioblast morphology surpasses that known previously for the entire family. Leaves are dorsiventral with mostly abaxial anomocytic stomata and typical palisade and spongy layers; paraveinal mesophyll is lacking. Miniature glandular (clavates, capitates) and nonglandular (mostly stellate) trichomes occur. Prismatic crystals predominate; epidermal prismatics and mesophyll druses are rare.     

Functional anatomy of five endangered tropical timber wood species of the family Dipterocarpaceae

Wood anatomy of five dipterocarp species endemic to the Philippines was studied with the goal to explore functional wood traits of ecological significance. Stem wood of 6-year-old trees grown under similar environmental conditions in a plantation (Leyte, Philippines) was used. Wood densities decreased in the following order Hopea plagata > Dipterocarpus kerrii > Parashorea malaanoman > Shorea almon ≈ Shorea contorta. This was mainly caused by significantly thicker fiber cell walls of H. plagata and D. kerrii than those of the other three species. Wood density was negatively correlated with the abundance of axial parenchyma cells. Predicted conductance was independent from wood density and lowest in H. plataga and highest in D. kerrii and S. contorta. These results indicate that H. plagata and D. kerrii is woods have higher constructions costs in term of carbon per unit of biomass, and that H. plagata is probably better acclimated to varying soil moisture than the other species.     

Wood anatomy of Polygonaceae: analysis of a family with exceptional wood diversity

Quantitative and qualitative data are presented for woods of 30 species of woody Polygonaceae. Wood features that ally Polygonaceae with Plumbaginaceae include nonbordered perforation plates, storeying in narrow vessels and axial parenchyma, septate or nucleate fibres, vasicentric parenchyma, pith bundles that undergo secondary growth, silica bodies, and ability to form successive cambia. These features are consistent with pairing of Plumbaginaceae and Polygonaceae as sister families. Wood features that ally Polygonaceae with Rhabdodendraceae include nonbordered perforation plates, presence of vestured pits in vessels, presence of silica bodies and dark-staining compounds in ray cells, and ability to form successive cambia. Of the features listed above, nonbordered perforation plates and ability to form successive cambia may be symplesiomorphies basic to Caryophyllales sensu lato . The other features are more likely to be synapomorphies. Wood data thus support molecular cladograms that show the three families near the base of Caryophyllales s.l. Chambered crystals are common to three genera of the family and may indicate relationship. Ray histology suggests secondary woodiness in Antigonon, Atraphaxis, Bilderdykia, Dedeckera, Eriogonum, Harfordia, Muehlenbeckia, Polygonum , and Rumex . Other genera of the family show little or no evidence of secondary woodiness. Molecular data are needed to confirm this interpretation and to clarify the controversial systematic groupings within the family proposed by various authors. Vessel features of Polygonaceae (lumen diameter, element length, density, degree of grouping) show an extraordinary range from xeromorphy to mesomorphy, indicating that wood has played a key role in ecological and habital shifts within the family; the diversity in ecology and habit are correlated with quantitative wood data.  © 2003 The Linnean Society of London. Botanical Journal of the Linnean Society , 2003, 141 , 25−51.     

Ecological wood anatomy ofAlnus nepalensis (Betulaceae) in East Nepal

Wood anatomical characters ofAlnus nepalensis growing in East Nepal are evaluated against three non-anatomical factors: tree height, diameter at breast height (DBH), and altitude. Samples were taken from the outermost part of the trunk of five canopy trees at 11 localities between 790 and 2,740 m above sea level. Tree height ranged from 10 to 28 m, and DBH ranged from 15 to 80 cm. Altitude and tree height are correlated with all the vessel characters studied. Among wood anatomical characters, vessel characters measured from cross sections are strongly correlated with one another, and are also correlated with vessel element and fiber-tracheid length. Multiple regression analysis using non-anatomical factors as independent variables resulted in significant correlation at 1% level in all pore characters, vessel element length, perforation plate bar number, and fibertracheid length. Regression coefficients of significant regressions are usually largest for altitude. For wood structure ofAlnus nepalensis in East Nepal, 23 to 42% of the variation is affected by non-anatomical factors. The large contribution of altitude is considered to be an indirect measure of the effect of temperature.     

Woods of the Vitaceae—fossil and modern

Vitaceoxylon tiffneyi gen. et sp. nov. and Vitaceoxylon carlquistii sp. nov. from the Middle Eocene Clarno formation are the oldest known woods with characteristics of the Vitaceae. They are characterized by a tendency to two diameter classes of vessels, wide and tall rays, and a high proportion of their area is vessel. Other characteristics include septate imperforate elements, scanty paratracheal to vasicentric parenchyma, idioblasts in the rays, crowded alternate intervessel pitting, and vessel-parenchyma pits with reduced borders. Wood anatomy of the major extant genera of Vitaceae was examined and compared to the fossils. Features of secondary xylem useful for distinguishing between genera in the Vitaceae include vessel size and arrangement (two distinct diameter classes or not, radial multiples or tendency to tangential multiples), vessel pitting (scalariform or alternate), crystal type (prismatic, druses, and/or raphides) and location (in chambered parenchyma and/or ray parenchyma), cambial variants (present or absent). Wood anatomy supports the proposed close relationship of Cissus to Cayratia. Pronounced vessel dimorphism occurs in temperate Vitaceae; cambial variant structure occurs in tropical Vitaceae. Despite their conformity with Vitaceae at the family level, the two fossil woods are not comparable to any one extant genus. This contrasts with the Vitaceae seeds from Clarno, all of which are referable to extant genera. Two new combinations for fossil woods of the Vitaceae are proposed: Vitaceoxylon ampelopsoides (Schönfeld) comb. nov., and Vitaceoxylon megyazoense (Greguss) comb. nov.     

Ethylene evolution changes in the stems of<Emphasis Type="Italic"> Metasequoia glyptostroboides</Emphasis> and<Emphasis Type="Italic"> Aesculus turbinata</Emphasis> seedlings in relation to gravity-induced reaction wood formation

Two-year-old Metasequoia glyptostroboides and 3-month-old Aesculus turbinata seedlings were tilted at a 45° angle to induce compression wood formation on the lower side of the former species and tension wood on the upper side of the latter. Two weeks later, the seedlings were tilted in an opposite direction at 45° so that the upper and lower sides changed to each other. This reverse tilting was kept for 7 weeks for M. glyptostroboides and 6 weeks for A. turbinata. The seedlings were sampled and analyzed at intervals throughout each experimental period so that an ethylene evolution kinetic was monitored. Ethylene evolution from the cambial region of the upper and lower sides of tilted stems was measured separately by gas chromatography with a flame ionization detector. Xylem production expressed as wood area during each experimental period was microscopically determined. In both tilting and reverse tilting periods, the rates of ethylene evolution from the lower side of M. glyptostroboides and the upper side of A. turbinata, where xylem production was accelerated and compression or tension wood formation was induced, had increased to high levels, whereas those from the opposite sides had either remained low (in tilting period) or rapidly recovered to low levels (in reverse tilting period). The cambial activity quantified by wood formation, including reaction wood, in both species showed the same tendency as ethylene evolution. The stem side with vigorous ethylene evolution, xylem development and reaction wood formation reversed with the reversal of tilting orientation. The roles of accelerated ethylene evolution in reaction wood formation in the tilted seedlings of gymnosperm and angiosperm trees are compared and discussed.This work was presented at the 5th Pacific Region Wood Anatomy Conference, Yogyakarta, Indonesia, 9–14 September 2002     

Caryophyllales: a key group for understanding wood anatomy character states and their evolution

Definitions of character states in woods are softer than generally assumed, and more complex for workers to interpret. Only by a constant effort to transcend the limitations of glossaries can a more than partial understanding of wood anatomy and its evolution be achieved. The need for such an effort is most evident in a major group with sufficient wood diversity to demonstrate numerous problems in wood anatomical features. Caryophyllales s.l., with approximately 12 000 species, are such a group. Paradoxically, Caryophyllales offer many more interpretive problems than other ‘typically woody’ eudicot clades of comparable size: a wider range of wood structural patterns is represented in the order. An account of character expression diversity is presented for major wood characters of Caryophyllales. These characters include successive cambia (more extensively represented in Caryophyllales than elsewhere in angiosperms); vessel element perforation plates (non‐bordered and bordered, with and without constrictions); lateral wall pitting of vessels (notably pseudoscalariform patterns); vesturing and sculpturing on vessel walls; grouping of vessels; nature of tracheids and fibre‐tracheids, storying in libriform fibres, types of axial parenchyma, ray anatomy and shifts in ray ontogeny; juvenilism in rays; raylessness; occurrence of idioblasts; occurrence of a new cell type (ancistrocladan cells); correlations of raylessness with scattered bundle occurrence and other anatomical discoveries newly described and/or understood through the use of scanning electron microscopy and light microscopy. This study goes beyond summarizing or reportage and attempts interpretations in terms of shifts in degrees of juvenilism, diversification in habit, ecological occupancy strategies (with special attention to succulence) and phylogenetic change. Phylogenetic change in wood anatomy is held to be best interpreted when accompanied by an understanding of wood ontogeny, species ecology, species habit and taxonomic context. Wood anatomy of Caryophyllales demonstrates problems inherent in binary character definitions, mapping of morphological characters onto DNA‐based trees and attempts to analyse wood structure without taking into account ecological and habital features. The difficulties of bridging wood anatomy with physiology and ecology are briefly reviewed. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164 , 342–393.