What Is “<i>Apocynum sibiricum</i>”? A Critical Comment on the Long-Term Taxonomic Homonymy

The necessity of the typification of the <i>Apocynum</i> L. s.l. (incl. <i>Poacynum</i> Baill. and <i>Trachomitum</i> Woodson) (Apocynaceae) species is crucial for future dogbane diversity estimations. Still, the original material of many taxa of the genus <i>Apocynum</i> s.l. is doubtful or remains to be discovered. This study’s topic is resolving a long-term taxonomic homonymy around the widely used binomial “<i>A. sibiricum</i>”. The misusing of the name “<i>A. sibiricum</i>” became a reason for long-term misunderstanding of the meaning of the binomial <i>Poacynum sarmatiense</i> (Woodson) Mavrodiev, Laktionov & Yu.E.Alexeev (<i>A. sarmatiense</i> (Woodson) Wissjul.; <i>T. sarmatiense</i> Woodson) and therefore for the misestimation of the <i>Apocynum</i> s.l. diversity in Russian and other Eurasian floras. Resolving this issue, here, we designate the lectotype of <i>A. sibiricum</i> Jacq. and the name “<i>A. sibiricum</i> Pall.” was validated within <i>Poacynum</i> as <i>P. pallasianum</i> Mavrodiev, Sytin, Laktionov & Vasjukov nom. nov. (<i>Apocynum sibiricum</i> auct., non Jacq.) with the lectotype selected from the original collections of Peter Simon Pallas.