Contribution to the native flora of Lithuania. First report /

Comprehensive and accurate information on the diversity and distribution of native plant species in an area is essential for understanding its biodiversity, assessing ongoing changes in the flora and providing timely protection for threatened species. Some important information cannot be used effectively because it remains unpublished in the notebooks of researchers or is published in social networks, ever-changing websites, or other ephemeral publications. With this article, we initiate the regular publication of the most important information on the diversity of native plant species in Lithuania, especially on the recorded new native taxa, the status of rare species and their populations. Orobanche bartlingii, which parasitises Libanotis pyrenaica, was recorded for the first time in eastern Lithuania (Utena distr.) in 2017. Although Orobanche bartlingii flowered every year, there was considerable variation in the number of flowering individuals between years. A large population of Polystichum aculeatum, consisting of more than 500 individuals, was found near Ignalina (Ignalina distr., eastern Lithuania). Crambe maritima in Lithuania was first reported in the literature in the 19th century. Still, it was not observed until 2022, when solitary individuals of this species were again found at two sites on the Baltic Sea coast (near Karklė, Klaipėda distr., and Juodkrantė, Neringa). Seeds of this species, which originate from other coastal regions of the Baltic Sea, have probably been washed ashore during storms. Solidago virgaurea subsp. pineticola, previously recorded at only one site in Lithuania, was found to be much more widespread in the southern and eastern parts of the country. This subspecies differs from Solidago virgaurea subsp. virgaurea not only in morphology but also in phenology. Solidago virgaurea subsp. pineticola starts flowering about one month earlier than Solidago virgaurea subsp. virgaurea. Conservation issues of Polystichum aculeatum and Crambe maritima were analysed and discussed.