Journal of Plant Development ISSN 2065-3158 print /e-ISSN 2066-9917 Vol. 30, Dec 2023: 17-32 Available online: www.plant-journal.uaic.ro doi: 10.47743/jpd.2023.30.1.922 Received: 28 April 2022 / Revised: 21 July 2023 / Accepted: 27 July 2023 NEW DATA ON THE DISTRIBUTION AND INVASION STATUS OF SOME ALIEN PLANTS IN ROMANIA Culiță SÎRBU 1* , Adrian OPREA 2 , Mihai DOROFTEI 3 , Silviu COVALIOV 3 1 “Ion Ionescu de la Brad” University of Life Sciences, Iaşi – Romania. 2 “Alexandru Ioan Cuza” University of Iaşi, Botanical Garden “Anastasie Fătu”, Iaşi – Romania. 3 National Research and Development Institute “Danube Delta”, Tulcea – Romania. * Corresponding author. E-mail: csirbu@uaiasi.ro, ORCID: 0000-0003-3217-0947 Abstract: In this paper we report new chorological data for 20 alien plant taxa from the vascular flora of Romania. A total of 9 species (Campsis radicans, Euphorbia glyptosperma, Grindelia squarrosa, Impatiens balfourii, Oenothera suaveolens, Robinia × ambigua, Rudbeckia triloba, Sedum sarmentosum, Setaria faberi) are reported as new to the regional floras within the country. Oenothera pycnocarpa and Dittrichia graveolens are reported in their second and the third sites in Romania, respectively. For the remaining 9 species (Cytisus scoparius, Dysphania pumilio, Eleusine indica, Erigeron sumatrensis, Eriochloa villosa, Oenothera depressa, Paspalum distichum, Rosa rugosa and Sicyos angulatus), we provided new field data, to improve knowledge on their current distribution and invasion status. All taxa are neophytes, introduced either accidentally (11 taxa) or deliberately (9 taxa), more than half of which are currently invasive or potentially invasive in the country. Keywords: chorological data, invasion status, neophytes, new floristic records, vascular flora. Introduction Research on alien flora, mainly on neophytes (i.e. alien plant species introduced after the year 1500, according to RICHARDSON & al. 2000), has registered notable development in recent decades in Romania. For all neophytes cited in the vascular flora of Romania until 2011, historical data on their distribution and invasive status in the country were previously extensively documented by ANASTASIU & NEGREAN (2009) and SÎRBU & OPREA (2011). After 2011, new data on neophytes from Romania were added by reporting on some previously unrecorded species [e.g.: ANASTASIU & MEMEDEMIN, 2012; OPREA & al. 2012; NAGODĂ & al. 2013; CAMEN-COMĂNESCU & al. 2016; NEGREAN & al. 2017; SÎRBU & OPREA, 2017; SÎRBU & ȘUȘNIA, 2018; SZATMARI & HURDU, 2020, etc.], but also by new contributions to knowledge on their distribution, habitat preferences and invasive status in the country [e.g.: SÎRBU & al. 2012; NAGODĂ, 2015; NEGREAN & al. 2017; OPREA & al. 2021; SÎRBU & al. 2021; ȘUȘNIA, 2022, etc.]. An extensive literature review on alien plant species (primarily neophytes) in Romania, covering the 1778-2018 time-period has been compiled recently [SÎRBU & al. 2022], resulting in a list of 102 invasive or potentially invasive alien plant species in the country. Field research on this topic increased substantially especially during 2019-2022, when the project “The adequate management of invasive species in Romania in accordance with EU Regulation” [Code SMIS 120008; https://invasive.ccmesi.ro/], coordinated by Dr. P. ANASTASIU, was carried out at the national level.