Annotated world taxonomic checklist of the genus Spiraea (Rosaceae)

Roman Businský

with 8 figures

Key words: Rosaceae, Spiraea, world natural diversity. – Taxonomy, synonymy, typifications, geographic distribution.

Summary
Businský R. 2025. Annotated world taxonomic checklist of the genus Spiraea (Rosaceae). – Phyton (Horn, Austria) 64–65: 85–144, with 8 figures.
The aim of this study is to provide a complete taxonomic evaluation of all validly published scientific names in the genus Spiraea. All previous publications addressing the taxonomy of this genus have focused only on selected species or individual species complexes or have been limited to regional floras. This is the first globally focused taxonomic checklist of the genus comprising all known world species elaborated down to the level of variety and supplemented with their geographic distribution and basic morphological classification. All accepted taxa include full synonymy, and for all valid names used, their nomenclatural types were traced and, in most cases, determined.
A total of 91 species, 3 subspecies and 36 varieties (excluding the autonymic taxa) were identified as constituting the world natural diversity of the genus Spiraea. In contrast, within accepted species, 133 names at the species level were found to comply with heterotypic synonyms, along with 130 heterotypic synonyms at the rank of variety and one of subspecies. Thirteen natural interspecific hybrids were distinguished, including three that originated spontaneously during cultivation and occasionally became naturalized. Twenty-three names at the species level and three at the rank of variety represent insufficiently known taxa whose names remain unresolved because they cannot be reliably taxonomically identified for various reasons. Altogether 654 fully cited names of various categories at the species level and below are included in the Checklist.
Within the compilation of the Checklist, 154 lectotypes, 9 neotypes, 13 epitypes (12 of them for lectotypes designated from original, mostly historical illustrations), and 40 synonyms were newly designated.