Cornales

1. Supertaxonomy Overview

Cornales, the dogwood order, is an ancient order of flowering plants and one of the earliest-diverging branches of the asterids. It includes dogwoods (Cornus), Alangium, hydrangeas (Hydrangea), tupelos (Nyssa), the dove tree (Davidia involucrata), camptotheca (Camptotheca), mastixioid trees such as Mastixia and Diplopanax, the highly specialized aquatic genus Hydrostachys, and the diverse stickleaf family Loasaceae. Although the order contains only a modest fraction of flowering-plant diversity, its principal living lineages separated early in asterid history and preserve an unusually rich record of Cretaceous diversification.

APG V, published in 2026, retains the same seven-family Cornales framework used by APG IV: Cornaceae, Curtisiaceae, Grubbiaceae, Hydrangeaceae, Hydrostachyaceae, Loasaceae, and Nyssaceae (Angiosperm Phylogeny Group 2026). Tree TSAR accepts the same ordinal core but recognizes eight living families: Alangiaceae, Cornaceae, Grubbiaceae, Hydrangeaceae, Hydrostachyaceae, Loasaceae, Mastixiaceae, and Nyssaceae. The difference is produced by three family-rank decisions rather than by a different concept of the order: Tree TSAR recognizes Alangiaceae and Mastixiaceae separately, while placing Curtisia with Grubbia in an expanded Grubbiaceae.

Under current generic circumscriptions, the Tree TSAR treatment contains roughly 40 living genera and more than 600 species, although exact totals remain fluid as large genera and species complexes are revised. The evolutionary structure of the order is more informative than a single count. Nuclear, plastid, fossil, and total-evidence studies consistently recover several ancient constituent radiations even where they disagree over the sequence of the deepest branches (Fu et al. 2019; Thomas et al. 2021; Nguyen & Atkinson 2024).

A useful biological throughline is the contrast between the predominantly woody, indehiscent or drupaceous lineages that dominate much of early Cornales and a major capsular/dehiscent radiation centered on Hydrangeaceae and Loasaceae. Hydrostachyaceae is often associated with the latter part of the order, but its exact attachment remains unusually difficult to resolve. This combination of ancient history, repeated morphological reinvention, familiar horticultural plants, and exceptionally informative fossil fruits makes Cornales an important Tree TSAR supertaxonomy unit.

2. Placement in Tree TSAR

Cornales is a formal angiosperm order within the Asterids, which in Tree TSAR are nested within Superasterids, Core Eudicots, Angiosperms, and ultimately Seed Plants. This higher framework is closely aligned with APG V, using strongly supported clades as navigational landmarks while avoiding unnecessary proliferation of formal ranks.

Cornales occupies a pivotal position near the base of asterid evolution. Together with Ericales, it diverged before the enormous radiation of the core asterids that later produced the lamiid and campanulid lineages. Genome-scale analyses consistently retain Cornales as one of the earliest branches of the asterid tree, even though the deepest asterid backbone has been affected by ancient rapid radiation, incomplete lineage sorting, and in some analyses signals of reticulation.

At the ordinal level, APG V reinforces rather than overturns the modern concept of Cornales. Its principal Cornales-specific comment concerns Hydrostachys: recent work continues to place the genus securely in Cornales, but different nuclear analyses have recovered it near Loasaceae or even as sister to the remainder of the order, while Thomas et al. (2021) identified ancient reticulation or incomplete lineage sorting as plausible sources of instability (Angiosperm Phylogeny Group 2026). Tree TSAR therefore treats the membership of Hydrostachyaceae in Cornales as secure but its exact nearest relatives as unresolved.

The order is especially useful as a Tree TSAR landmark because a reader can enter through a familiar dogwood, hydrangea, tupelo, dove tree, or blazing-star and move directly into one of the earliest major experiments in asterid evolution. The principal disagreements among modern classifications concern the placement of family rank inside this stable ordinal framework, not whether these major lineages belong to Cornales.

3. Evolutionary History and Fossil Context

Cornales is ancient even by the standards of flowering-plant orders. Molecular dating repeatedly places its origin and initial diversification in the Cretaceous. Fu et al. (2019) inferred a mid-Cretaceous origin followed by unusually rapid separation of the principal living lineages, a pattern that helps explain why short internal branches and conflicting genomic histories remain visible in modern phylogenetic datasets.

The fossil record independently shows that Cornales had become anatomically diverse by about 90 million years ago. Fossil fruits from eastern Asia and both eastern and western North America occur by the Turonian-Coniacian interval, implying that the first divergences of the order began earlier. Atkinson and colleagues have argued that the initial radiation may extend toward approximately 100-96 million years ago. By the Late Cretaceous, several distinctive cornalean fruit architectures were already geographically widespread.

Fruits and endocarps are unusually informative in this order. Germination valves, locular arrangement, vascular systems, endocarp tissues, and related anatomical features can preserve enough structure to compare fossil taxa directly with living clades. Fossils such as Hironoia, Eydeia, Operculifructus, and diverse mastixioid fruits show that several lineages once occupied regions far beyond their modern ranges. The present distributions of many Cornales are therefore relictual remnants of much broader Cretaceous and Paleogene histories.

The fossil record also cautions against projecting the living family system backward unchanged. Nguyen & Atkinson (2024) recovered Fenestracarpa washingtonensis and several other fossils in an entirely extinct major cornalean lineage rather than within any extant family. Modern Cornales is consequently a pruned remnant of a once richer radiation. Small living groups such as Curtisia, Grubbia, and Davidia may represent surviving tips of ancient lineages rather than evolutionarily young taxa.

This history is also why Tree TSAR does not assign ranks by age alone. Late Cretaceous divergences recur at several hierarchical levels: between recognized families, among deep subfamilies, and even among major clades inside broad genera such as Cornus. Divergence time is therefore most useful when it corroborates monophyly, morphological diagnosability, genomic independence, and taxonomic utility rather than when treated as an automatic rank threshold.

4. Classification and Circumscription

Cornales has one of the more instructive classification histories among the major angiosperm orders. Earlier morphology-based systems accumulated a variety of woody groups around Cornaceae because of similarities in habit, inferior ovaries, simple leaves, and fleshy fruits. Molecular evidence eventually stabilized the modern core order, but the rapid early radiation of Cornales means that family boundaries and a few deep relationships remain more debatable than the membership of the order itself.

The APG V baseline

APG V recognizes seven families in Cornales: Cornaceae, Curtisiaceae, Grubbiaceae, Hydrangeaceae, Hydrostachyaceae, Loasaceae, and Nyssaceae. It does not announce a revised family circumscription for the order, so the APG IV seven-family framework remains the current APG baseline. APG V nevertheless explicitly highlights the uncertain position of Hydrostachyaceae and the possibility that ancient reticulation or incomplete lineage sorting contributes to conflicting placements (Angiosperm Phylogeny Group 2026).

Tree TSAR recognizes eight families. This should not be interpreted as a general preference for narrower families. The project separates some ancient, independently diagnosable crown radiations, combines other historically separated families where the surviving lineage is more coherent as a whole, and retains several broad families despite very old internal splits. The resulting treatment is intended to express the biological architecture of each lineage rather than to apply a uniform lumping or splitting rule.

Cornaceae and Alangiaceae

Cornus and Alangium are robustly supported sister lineages. APG V and the current Kew backbone place both in Cornaceae sensu lato, a treatment that is fully monophyletic. Tree TSAR instead recognizes Cornaceae sensu stricto for Cornus and Alangiaceae for Alangium. The two-family treatment is equally monophyletic and is supported in recent specialist phylogenomic and paleobotanical work (Thomas et al. 2021; Du et al. 2023; Nguyen & Atkinson 2024).

Tree TSAR treats the family boundary as a convergence of evidence rather than a consequence of antiquity alone. Alangium forms a species-rich, reciprocally coherent crown lineage with a distinctive suite of vegetative, floral, ovarian, vascular, indumentum, and fruit characters; its living crown was estimated by Feng et al. (2009) at about 77.7 million years old. Recognition of Alangiaceae also carries exceptionally low nomenclatural cost because the established family name is restored without changing the generic or species combinations of Alangium. APG V’s broader Cornaceae remains a scientifically legitimate alternative whose principal advantage is interoperability with a major global classification.

The same decision does not require fragmenting Cornus. Broad Cornus is itself strongly monophyletic and possesses a coherent morphological and genomic identity, including a shared dogwood structural framework and an ancient whole-genome duplication on the stem preceding its major living radiations (Yu et al. 2017; Du et al. 2023). Its deep internal branches are expressed through clades and subgenera. Family rank between Alangium and Cornus, and genus rank within the dogwood crown, are separate comparative questions.

Grubbiaceae and the position of Curtisia

APG V retains Curtisiaceae and Grubbiaceae as separate families. Tree TSAR instead recognizes Grubbiaceae sensu lato for Grubbia and Curtisia. Molecular datasets repeatedly join the two, and total-evidence work has identified fruit-anatomical characters supporting the combined lineage. Because the entire living crown comprises only a few surviving species divided between two deeply relictual branches, Tree TSAR treats their divergence within one family rather than assigning family rank to each remnant stem.

Nyssaceae and Mastixiaceae

APG V retains a broad Nyssaceae containing Nyssa, Camptotheca, Davidia, Mastixia, and Diplopanax. Tree TSAR separates the mastixioid lineage as Mastixiaceae, containing Mastixia and Diplopanax, while retaining Nyssa, Camptotheca, and Davidia in Nyssaceae. The mastixioids possess a distinctive reproductive, floral, fruit-anatomical, biogeographic, and fossil history that supports family recognition. Davidia, despite its conspicuous morphology and deep stem history, remains in Nyssaceae because the three-genus nyssoid crown shows substantial developmental and genomic cohesion.

Hydrangeaceae, Loasaceae, and Hydrostachyaceae

Here Tree TSAR and APG V agree at family rank: Hydrangeaceae, Loasaceae, and Hydrostachyaceae are retained as separate families. Hydrangeaceae and Loasaceae are especially well supported as reciprocally monophyletic radiations. A densely sampled 2025 study recovered both with strong support and estimated their divergence within an approximately 79.5-92.6 million-year interval in the Late Cretaceous (Schenk et al. 2025). The two families share enough structure to make their relationship intelligible, including a major transition toward capsular fruits, yet each has developed a coherent and independently diagnosable morphology, ecology, and biogeographic history.

The deepest lineages inside both families remain below family rank. Jamesioideae and Hydrangeoideae diverged early within Hydrangeaceae, while several major Loasaceae subfamily stems also extend far into the Paleogene or Late Cretaceous. Those ages are biologically important, but neither broad family loses its monophyly, morphological coherence, or classificatory usefulness by retaining those lineages at infr familial rank. This is a particularly clear example of the Tree TSAR principle that temporal equivalence provides context rather than automatic rank.

Hydrostachyaceae is the difficult topological element. Plastid and some nuclear analyses have recovered Hydrostachyaceae + (Hydrangeaceae + Loasaceae), and this remains a useful working hypothesis. Other total-evidence and nuclear analyses place Hydrostachys differently, including close to Loasaceae or near the base of the remaining order. APG V explicitly preserves the family in Cornales while declining to force a single immediate sister relationship. Tree TSAR follows that caution: Hydrostachyaceae is a secure family of Cornales, but the exact three-way topology around the capsular lineages remains provisional.

The resulting Tree TSAR classification is therefore not a mechanically narrower alternative to APG V. It is narrower than APG V around Cornus-Alangium and the mastixioids, broader around Curtisia-Grubbia, and identical to APG V for Hydrangeaceae, Loasaceae, and Hydrostachyaceae. The pattern is deliberately non-mechanical: rank follows the convergence of phylogeny, diagnosability, evolutionary depth, taxonomic cohesion, and nomenclatural utility.

5. Morphology, Biology, and Identification

No single visible character diagnoses every member of Cornales. The order is too old, and its living families too morphologically diverse, for a simple field rule. Nevertheless, several recurring features characterize much of the order and help explain why many of its woody lineages were historically associated. Flowers are commonly epigynous, with the floral organs positioned above an inferior or partly inferior ovary, and floral nectary discs are widespread. Many woody Cornales have comparatively small, radially symmetrical flowers with four or five perianth parts.

The predominantly woody lineages commonly produce fleshy or otherwise indehiscent fruits with a hardened inner fruit wall. Endocarp anatomy has become one of the most powerful comparative systems in the order: locule number, germination valves, ridges, tissue composition, and vascular architecture can distinguish living families and connect them to fossil fruits tens of millions of years old. This anatomical continuity is a major reason Cornales has become so important in paleobotany.

Cornaceae sensu Tree TSAR illustrates how a major lineage can remain morphologically coherent despite striking internal diversity. Broad Cornus retains a recognizable suite that includes simple entire leaves with arcuate venation, characteristic two-armed hairs, predominantly opposite phyllotaxy, four-merous flowers, an inferior ovary, and drupaceous fruits. The spectacular clade-level differences in involucral bracts, inflorescence architecture, habit, and fruit color are superimposed on this shared framework rather than replacing it. Even showy-bract characters are evolutionarily labile: Cornus disciflora, for example, develops four involucral bracts but sheds them before they expand and become petaloid, despite being closely allied to eastern flowering dogwood (C. florida).

The contrast with Alangiaceae is therefore best understood as a suite rather than a single diagnostic character. Alangium characteristically has alternate leaves, commonly axillary inflorescences, more numerous and variable floral parts, distinctive gynoecial vascular anatomy, and lacks the characteristic two-armed hairs of dogwoods. Individual exceptions occur on both sides, but the correlated character sets reinforce the long independent histories of the two sister lineages.

Hydrangeaceae and Loasaceae represent a different evolutionary direction. Character reconstruction places a transition toward capsular fruits on the branch associated with their shared history, and both families include distinctive trichome systems. Hydrangeaceae remains predominantly woody, with shrubs, trees, vines, and some herbaceous derivatives. Loasaceae underwent a major herbaceous radiation and includes plants with scabrid, glochidiate, or stinging mineralized hairs, highly specialized androecia and staminodes, and elaborate pollination mechanisms. Their shared ancestry remains recognizable even though their modern biological syndromes are profoundly different.

Hydrostachyaceae is the morphological extreme. Species of Hydrostachys are rheophytes anchored to rocks in fast-flowing African and Madagascan streams. Their leaves may be deeply divided or covered in unusual appendages, and their flowers are so reduced that historical botanists repeatedly misplaced them. Large nuclear and plastid datasets now secure the family in Cornales even while its exact position within the order remains unstable (Xu et al. 2024; Angiosperm Phylogeny Group 2026).

Conspicuous display structures have also evolved repeatedly and independently across Cornales. Big-bracted dogwoods enlarge involucral bracts; many hydrangeas enlarge sterile peripheral flowers; and the dove tree produces enormous white bracts around compact reproductive structures. These parallel solutions help explain the horticultural prominence of Cornales, but they should not be mistaken for evidence that the lineages producing them are immediately related.

6. Distribution and Ecology

Cornales is nearly worldwide in collective distribution, but many of its component lineages show striking disjunctions and relictual patterns. Temperate and subtropical eastern Asia, North America, tropical mountains, southern Africa, Madagascar, and the Neotropics all contain important portions of the order. Modern distributions often preserve only fragments of ranges that were much broader during the Cretaceous and Paleogene.

The Cornaceae-Alangiaceae pair illustrates complementary biogeographic histories. Dogwoods are especially diverse across the temperate Northern Hemisphere, with additional montane and tropical representatives from Africa through the Americas and southeastern Asia. Alangium, by contrast, is centered in the Old World tropics and subtropics, ranging from tropical Africa across southern and eastern Asia to the southwest Pacific. Their modern geography mirrors long independent diversification after an ancient sister-lineage split.

The nyssoid and mastixioid lineages preserve another mixture of temperate and tropical history. Nyssa includes the tupelos of eastern North America together with smaller Asian and Mesoamerican components; Camptotheca and Davidia are eastern Asian lineages; and Mastixia and Diplopanax are predominantly Asian tropical or subtropical trees. Their abundant fossil record shows that the modern distributions are remnants of much wider former ranges.

Grubbiaceae sensu Tree TSAR is now restricted to southern Africa. Curtisia dentata is a forest and woodland tree, while Grubbia comprises specialized Cape shrubs associated particularly with fynbos. Their ecological contrast is striking, but fossil evidence demonstrates that relatives of the combined lineage once occurred far outside its present range. The modern distribution is therefore relictual rather than representative of the clade’s full history.

Hydrangeaceae and Loasaceae appear to have shared an ancient western North American-Mesoamerican context before following sharply different trajectories. Hydrangeaceae diversified largely among woody forest and woodland habitats across temperate and subtropical regions, especially eastern Asia and the Americas. Loasaceae became predominantly herbaceous and especially diverse in the Americas, radiating into deserts, seasonally dry habitats, high-elevation Andean environments, and other open vegetation. Recent comparative work treats this contrast as the outcome of two ancient sister radiations rather than simply a difference between family labels (Schenk et al. 2025).

Hydrostachyaceae occupies an ecological niche unlike any other family in the order. Its species live in rapidly flowing freshwater habitats in Madagascar and continental Africa, where they adhere to submerged or seasonally exposed rocks. Their extreme rheophytic specialization demonstrates how profoundly ecology can transform morphology while deeper genomic evidence still preserves a lineage’s ordinal ancestry.

7. Human Uses and Cultural Importance

Several Cornales lineages are among the most familiar ornamental woody plants of temperate horticulture. Dogwoods are cultivated for floral displays, colorful fruits, autumn foliage, bark, growth habit, and wildlife value. Eastern flowering dogwood (Cornus florida), Pacific flowering dogwood (C. nuttallii), Japanese kousa dogwood (C. kousa), European cornelian-cherry dogwood (C. mas), and numerous shrubby dogwoods have long horticultural or cultural histories. European cornelian-cherry dogwood also has an extensive food tradition, while Japanese cornelian-cherry dogwood (C. officinalis) is important in East Asian medicinal cultivation.

Hydrangeas are among the world’s most widely cultivated ornamental shrubs and climbers. Garden selections span mophead, lacecap, panicle, oakleaf, climbing, mountain, and other horticultural groups. The wider family contributes mock-oranges (Philadelphus), deutzias (Deutzia), and a range of less widely grown shrubs and perennials.

The dove tree, Davidia involucrata, is prized for the enormous white bracts surrounding its flower heads and became one of the celebrated ornamental introductions from China. Tupelos such as Nyssa sylvatica are valued as landscape and wildlife trees, and wetland species are ecologically important components of southeastern North American swamps.

Camptotheca acuminata has particular scientific and medicinal importance because camptothecin was first isolated from this tree. The parent compound is too toxic for routine therapeutic use, but its chemistry led to major anticancer drugs derived from camptothecin. The genus therefore occupies a distinctive place at the intersection of plant systematics, natural-products chemistry, and medicine.

Loasaceae is less prominent economically but includes horticulturally distinctive blazing-stars and stickleafs of Mentzelia and striking Andean genera such as Loasa, Nasa, and Caiophora. Their complex flowers, stinging or barbed hairs, and specialized pollination systems have made the family especially important in evolutionary and ecological research. More broadly, Cornales has become a model for studying ancient rapid radiation, fossil calibration, historical biogeography, fruit evolution, reticulation, and the difficulty of reconciling gene trees after Cretaceous diversification.

8. Conservation Significance

Conservation concerns within Cornales are highly uneven and should be evaluated at family, genus, population, and species levels rather than generalized across the order. The same lineage can contain widespread horticultural species, poorly known tropical taxa, and exceptionally old relicts with tiny modern ranges.

Many Cornales occupy forests and other habitats threatened by land conversion, fragmentation, logging, altered hydrology, invasive species, emerging pathogens, and climate change. Narrowly distributed tropical, montane, and island species can be especially vulnerable. Ancient relict lineages deserve particular attention because extinction of a single species may erase a disproportionate amount of evolutionary history.

Hydrostachyaceae presents a distinctive conservation problem. Its species depend on fast-flowing freshwater habitats, so altered river flow, sedimentation, watershed disturbance, pollution, or hydrological development can affect entire local populations. The concentration of endemic Hydrostachys species in Madagascar adds geographic vulnerability to an already specialized ecological strategy.

Southern African Grubbiaceae combines similarly high evolutionary distinctiveness with low living diversity. Curtisia and the few living Grubbia species represent remnants of a much older lineage whose fossil history extends far beyond its modern range. The Asian relict trees Davidia, Camptotheca, Diplopanax, and several mastixioids likewise preserve evolutionary histories much larger than their present-day distributions suggest.

Cornaceae provides a complementary conservation lesson. Broad Cornus contains both common species and narrowly distributed or genomically structured lineages. Dogwood anthracnose has caused major ecological damage to eastern flowering dogwood and Pacific flowering dogwood in North America, while genomic work on bunchberries demonstrates that apparently broad species can conceal differentiated cytotypes and reticulate lineages. Provenance therefore matters in both wild and ex situ conservation.

Cornales as a whole is not uniformly threatened. Its conservation significance lies in the juxtaposition of familiar garden plants with species and lineages that represent irreplaceable branches of the early asterid tree. Species counts alone can badly underestimate that evolutionary value.

9. Major Included Groups

The deepest branching pattern of Cornales is not completely settled, but several major evolutionary complexes recur across molecular, genomic, morphological, and fossil analyses.

The Cornaceae-Alangiaceae lineage contains dogwoods and Alangium. Tree TSAR recognizes them as sister families, with broad Cornus retained within Cornaceae and Alangium forming Alangiaceae. APG V instead unites both genera in Cornaceae sensu lato. The disagreement is one of family rank, not of their sister relationship.

Grubbiaceae sensu lato contains the southern African genera Grubbia and Curtisia. Tree TSAR treats their strong molecular relationship and shared fruit-anatomical evidence as best expressed within one family. APG V retains Curtisiaceae separately.

The nyssoid-mastixioid radiation contains Mastixiaceae and Nyssaceae in Tree TSAR. Mastixiaceae comprises Mastixia and Diplopanax; Nyssaceae contains Nyssa, Camptotheca, and Davidia. APG V instead places all five genera in Nyssaceae. These lineages possess an exceptional fossil record that documents their former abundance and geographic breadth.

The Hydrangeaceae-Loasaceae radiation is one of the best-supported higher relationships in the order. The two families are reciprocally monophyletic, share a recognizable capsular evolutionary background, and diverged deep in the Late Cretaceous, but each is independently large and morphologically coherent enough to retain family rank. Hydrostachyaceae is frequently recovered near this radiation and may be its sister lineage under the preferred Tree TSAR working topology, but its exact immediate position remains the least stable element of the living Cornales backbone.

Together these groups show why Cornales cannot be understood simply as “dogwoods and their relatives.” The order encompasses ancient forest trees, tropical relicts, temperate shrubs, lianas, elaborate herbaceous flowers, stinging plants, dryland radiations, and specialized aquatic herbs. Its modern diversity is the surviving residue of a much richer Cretaceous experiment in asterid evolution.

10. Similar, Overlapping, or Historically Confused Groups

The name Cornales has not always referred to the same collection of plants. Older morphology-based classifications associated Cornaceae with several woody lineages that molecular data later removed from the order. Garrya is now placed in Garryales, while Griselinia and Torricellia belong with lineages associated with Apiales. Similarity in woody habit, simple leaves, inferior ovaries, or fleshy fruits proved insufficient to establish close ancestry.

The term Cornaceae itself also varies among current sources. APG V and Kew use Cornaceae sensu lato for Cornus + Alangium, whereas Tree TSAR recognizes Alangiaceae and restricts Cornaceae to Cornus sensu lato. This distinction should remain explicit wherever family names are compared; otherwise identical labels can conceal different circumscriptions.

Nyssaceae likewise differs between systems. APG V and Kew include Nyssa, Camptotheca, Davidia, Mastixia, and Diplopanax in one family. Tree TSAR recognizes Mastixiaceae for the last two genera while retaining Davidia with the nyssoid lineage rather than resurrecting Davidiaceae.

Curtisiaceae presents the reverse situation. APG V recognizes it separately from Grubbiaceae, but Tree TSAR places Curtisia and Grubbia together in Grubbiaceae sensu lato. The Tree TSAR system therefore cannot be described accurately as simply more split or more lumped than APG V; it differs in the placement of boundaries on a case-by-case basis.

Hydrostachyaceae has also been historically confused with unrelated aquatic plants because convergent adaptation to rapid-flowing water produced an extraordinary body plan. Modern genome-scale evidence firmly places Hydrostachys in Cornales, but APG V appropriately emphasizes that its immediate position within the order remains unsettled.

Finally, Cornales should not be confused with Cornaceae. Cornaceae is only one family within the order, even though the similarity of the names and the prominence of dogwoods can make the terms appear interchangeable.

11. Additional Information

Useful external resources include Plants of the World Online for Kew’s current global taxonomic backbone; the APG V publication for the current Angiosperm Phylogeny Group family list and discussion of difficult placements; the Angiosperm Phylogeny Website for detailed synthesis of Cornales relationships, morphology, fossils, and competing classifications; the Kew Tree of Life Explorer for phylogenomic placement; World Flora Online for comparison of accepted names and alternatives; GBIF for occurrence data; and the Paleobiology Database for fossil records.

Readers should expect family assignments to differ among these resources. In most cases the difference concerns where family rank is drawn inside strongly supported cornalean lineages, not whether the major groups belong to the order. Tree TSAR therefore emphasizes explicit circumscription notes whenever its family boundaries differ from APG V or Kew.

12. References and Further Reading

Angiosperm Phylogeny Group. 2026. Large-scale nuclear and plastid phylogenomic analyses inform an updated Angiosperm Phylogeny Group classification: APG V. Journal of Systematics and Evolution. DOI: 10.1111/jse.70096 (opens in a new tab).

Atkinson, B. A., Martínez, L. C. A. & Crepet, W. L. 2019. Eydeia jerseyensis sp. nov. (Cornales) from the Upper Cretaceous of eastern North America. Annals of Botany 123: 451-460. DOI: 10.1093/aob/mcy170 (opens in a new tab).

Du, Z.-Y., Xiang, Q.-Y. J., Cheng, J., Zhou, W., Wang, Q.-F., Soltis, D. E. & Soltis, P. S. 2023. An updated phylogeny, biogeography, and PhyloCode-based classification of Cornaceae based on three sets of genomic data. American Journal of Botany 110: e16116. DOI: 10.1002/ajb2.16116 (opens in a new tab).

Feng, C.-M., Manchester, S. R. & Xiang, Q.-Y. 2009. Phylogeny and biogeography of Alangiaceae (Cornales) inferred from DNA sequences, morphology, and fossils. Molecular Phylogenetics and Evolution 51: 201-214. DOI: 10.1016/j.ympev.2009.01.017 (opens in a new tab).

Fu, C.-N., Mo, Z.-Q., Yang, J.-B., Ge, X.-J., Li, D.-Z., Xiang, Q.-Y. J. & Gao, L.-M. 2019. Plastid phylogenomics and biogeographic analysis support a trans-Tethyan origin and rapid early radiation of Cornales in the Mid-Cretaceous. Molecular Phylogenetics and Evolution 140: 106601. DOI: 10.1016/j.ympev.2019.106601 (opens in a new tab).

Hayes, R. F. et al. 2018. Cornalean affinities, phylogenetic significance, and biogeographic implications of Operculifructus infructescences from the Late Cretaceous (Campanian) of Mexico. American Journal of Botany 105. DOI: 10.1002/ajb2.1179 (opens in a new tab).

Nguyen, A. T. & Atkinson, B. A. 2024. Cretaceous and Paleocene fossils reveal an extinct higher clade within Cornales, the dogwood order. American Journal of Botany 111: e16372. DOI: 10.1002/ajb2.16372 (opens in a new tab).

Royal Botanic Gardens, Kew. 2026. Plants of the World Online / World Checklist of Vascular Plants taxonomic backbone. Current Cornales treatments include broad Cornaceae and five-genus Nyssaceae.

Schenk, J. J., Jacobs, B. F. & Hufford, L. 2025. Comparative diversification analyses of Hydrangeaceae and Loasaceae reveal complex evolutionary history as species disperse out of Mesoamerica. American Journal of Botany 112: e16455. DOI: 10.1002/ajb2.16455 (opens in a new tab).

Thomas, S. K., Liu, X., Du, Z.-Y., Dong, Y., Cummings, A., Pokorny, L., Xiang, Q.-Y. J. & Leebens-Mack, J. H. 2021. Comprehending Cornales: phylogenetic reconstruction of the order using the Angiosperms353 probe set. American Journal of Botany 108: 1112-1121. DOI: 10.1002/ajb2.1696 (opens in a new tab).

Xiang, Q.-Y. J., Thomas, D. T. & Xiang, Q. P. 2011. Resolving and dating the phylogeny of Cornales: effects of taxon sampling, data partitions, and fossil calibrations. Molecular Phylogenetics and Evolution 59: 123-138. DOI: 10.1016/j.ympev.2011.01.016 (opens in a new tab).

Xu, Z., Folk, R. A., Gitzendanner, M. A., Hu, G.-W., Soltis, P. S., Soltis, D. E. & Wang, Q.-F. 2024. Re-examining the placement of Hydrostachys using a large-scale phylogenetic approach. Taxon 73: 237-248. DOI: 10.1002/tax.13122 (opens in a new tab).

Yu, Y., Xiang, Q.-Y., Manos, P. S., Soltis, D. E., Soltis, P. S., Song, B.-H., Cheng, S., Liu, X. & Wong, G. K.-S. 2017. Whole-genome duplication and molecular evolution in Cornus L. (Cornaceae): insights from transcriptome sequences. PLOS ONE 12: e0171361. DOI: 10.1371/journal.pone.0171361 (opens in a new tab).

Zhang, C. et al. 2020. Asterid phylogenomics/phylotranscriptomics uncover morphological evolution, gene duplication, and whole-genome duplication histories. Molecular Biology and Evolution 37: 3188-3210.