As the largest genus in the subfamily Pertyoideae of the sunflower family (Asteraceae), Ainsliaea is widely distributed in East Asia and the Himalayas, playing a key role in various plant communities with significant ecological and scientific importance.

For a long time, the classification of Ainsliaea has faced many challenges, due to discrepancies between traditional morphological classifications and conflicts with molecular phylogenies, which have led to controversies in species delimitation and infrageneric classification.

To address these challenges, researchers from Wuhan Botanical Garden collaborated closely with multiple domestic research institutions, conducted extensive fieldwork, and meticulously studied a large number of specimens from major herbaria both domestically and internationally. They used molecular data to reconstruct the phylogeny of Ainsliaea, revealing the phylogenetic relationships and evolutionary pathways of key traits among species.

Researchers rediscovered Ainsliaea nana in the Wolong and Huanglong nature reserves in Sichuan, confirming its status as an endangered endemic species in western Sichuan, which had not been collected since over 60 years ago.

Through detailed observations of the variation in habits (i.e., leaf arrangements) of A. nana and other controversial species, researchers revealed the complex patterns of evolution in habits within Ainsliaea and summarized four evolutionary pathways.

This work not only reaffirmed growth habit as a "good" diagnostic trait for the classification of Ainsliaea but also indicated the plasticity of this trait and the possible occurrence of parallel evolution in specific growth stages or habitats, laying a solid foundation for taxonomic research.

Combining comprehensive molecular systematic and morphological analyses, the research team updated the infrageneric classification system of Ainsliaea, subdividing it into two subgenera and four sections, including two new sections established in this study: sect. Alternae and sect. Intermediae. Furthermore, revisions were made to the classification of three key species, A. lancifolia, A. nana, and A. pertyoides, providing updated taxonomic information including synonyms, type specimens, morphological descriptions, habitats, endangered status, distributions, etc.

These achievements not only enrich the taxonomy of the genus Ainsliaea, but also provide direction for future research, emphasizing the importance of integrating multiple lines of evidence in species classification. They also reveal the need for a comprehensive understanding of trait variation and evolutionary patterns through the combined application of correct species delimitation, meticulous field and specimen observations, and insights from molecular systematics.

The research findings, titled "An updated phylogeny ofAinsliaea(Asteraceae: Pertyoideae) and its implications for classification and habit evolution", were recently published in the journal Taxon. ZHANG Caifei and TIAN Jing are the first authors, and Professors WANG Qingfeng, HU Guangwan and GAO Tiangang co-supervised this study.

This study was financially supported by the Second Tibetan Plateau Scientific Expedition and Research Program, National Plant Specimen Resource Center, the Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment of China and the National Natural Science Foundation of China.

Molecular phylogeny and new classification of Ainsliaea (Image by WBG)

Ainsliaea nana (Arrows show inflorescence with cleistogamous florets) (Image by WBG)

Diverse leaf arrangements in Ainsliaea (Image by WBG)

Presumed evolution of leaf arrangements in Ainsliaea (Image by WBG)