Cornus sp. “04-C33” — Guizhou evergreen dogwood

Introduction

Cornus sp. “04-C33” is Tree TSAR’s placeholder for a deeply divergent Syncarpea lineage represented in genomic studies by the voucher Xiang 04-C33. The available nuclear data place it apart from ordinary C. capitata and close to the lineage containing C. sunhangii and C. capitata, with divergence deep enough that Du and colleagues treated it as a probable species-level entity rather than one of the younger population subdivisions within the eastern Asian radiation (Du et al. 2023, 2024).

The biological conclusion is stronger than the nomenclature. Sequence records have called the voucher “C. capitata ssp. brevipedunculata” or similar variants, but the type-based botanical names Dendrobenthamia brevipedunculata and Cornus capitata ssp. brevipedunculata are currently placed with C. hongkongensis ssp. tonkinensis. The available voucher trail does not securely connect Xiang 04-C33 to that nomenclatural type. Tree TSAR therefore recognizes the lineage while withholding a binomial rather than attaching an epithet that may belong to a different plant.

The common name Guizhou evergreen dogwood is a Tree TSAR editorial label for navigation. It should not be treated as evidence that the exact sequenced voucher locality has been independently verified; the published genomic records available to Tree TSAR do not yet provide the type-to-voucher reconciliation needed for a formal name.

Horticultural and Agricultural Uses

No authenticated horticultural material can presently be discussed under the 04-C33 lineage with confidence. Plants in cultivation labeled “brevipedunculata” should not automatically be transferred here because that name belongs to a different type-based taxonomic concept.

If verified living material becomes available, documented provenance and a voucher linked to the genomic lineage will be essential. Until then, the taxon is chiefly a research entity rather than a horticultural one.

Conservation Concerns

No conservation assessment is possible from the present information. The geographic and population limits of the lineage have not been established securely enough to estimate range size, population trend, or habitat exposure.

The immediate conservation task is taxonomic and field based: relocate or authenticate the genomic population, connect living or herbarium vouchers to the 04-C33 sequence identity, and sample additional populations. Only after that bridge is built can rarity or threat be evaluated without confusing this lineage with formal brevipedunculata material of ssp. tonkinensis.

Additional Information

2023 Cornaceae phylogenomics study (opens in a new tab) — Places Xiang 04-C33 in the genomic framework of Cornaceae.
2024 Benthamidia RAD-seq study (opens in a new tab) — Primary species-delimitation and biogeographic evidence for the distinct lineage.
Plants of the World Online — formal brevipedunculata placement (opens in a new tab) — Shows the type-based brevipedunculata name cluster under C. hongkongensis ssp. tonkinensis, not 04-C33.

References and Further Reading

Du Z-Y, Cheng J, Xiang Q-Y (2024) RAD-seq data provide new insights into biogeography, diversity anomaly, and species delimitation in eastern Asian–North American disjunct clade Benthamidia of Cornus (Cornaceae). Journal of Systematics and Evolution 62(1): 1–19. https://doi.org/10.1111/jse.13037 (opens in a new tab)

Du Z-Y, Xiang Q-Y, Cheng J, Zhou W, Wang Q-F, Soltis DE, Soltis PS (2023) An updated phylogeny, biogeography, and PhyloCode-based classification of Cornaceae based on three sets of genomic data. American Journal of Botany 110(2): e16116. https://doi.org/10.1002/ajb2.16116 (opens in a new tab)

Royal Botanic Gardens, Kew (2026) Cornus hongkongensis ssp. tonkinensis (W.P.Fang) Q.Y.Xiang. Plants of the World Online. https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:953433-1 (opens in a new tab)