Complete Plastome of Carlina acaulis and Implications on Systematics of the Tribe Cardueae (Asteraceae)

Carlina acaulis (Asteraceae) is a herb native to central and southern Europe. We determined its complete plastome using genome skimming. The plastome is 153 206 bp long, with a pair of inverted repeat (IR) regions (25 147 bp), one large single-copy region (84 343 bp), and one small single-copy region (18 569 bp). It contains 132 genes, including 88 protein-coding genes, eight ribosomal RNA genes, and 36 transfer RNA genes, 19 of which are duplicated within the IRs. Phylogenetic analyses based on 25 plastomes of the tribe Cardueae indicate that C. acaulis is closely related to the genus Atractylodes. A subtribal classification proposed in 2019 is well supported, except that Synurus (subtribe Onopordinae) is nested within the subtribe Saussureinae, which might be due to misidentification. Our work contributes to the study of the evolutionary history of the tribe Cardueae and the genetic resources of C. acaulis.