The yellow flag, Iris pseudacorus L. (Iridaceae) is an emergent perennial wetland plant native to the Palearctic region and has been dispersed worldwide as an ornamental plant. In the introduced range, it is highly invasive in natural and artificial waterbodies. Currently, this species is difficult to manage and continues to spread, causing significant environmental impacts. The aims of this study were to assess the geographical range of I. pseudacorus in Argentina by compiling data from literature, collections, citizen science and field surveys. An exhaustive review of herbarium collections and literature was conducted and a database with reports obtained through citizen science was obtained and used to design routes for field surveys. 114 records of I. pseudacorus were obtained, mainly in humid and disturbed areas. The oldest records date from 1931 and 1933, and the number of reported localities showed a gradual increase with time. Fifteen records of the weed were from protected areas, four of which have international conservation status. This study shows that I. pseudacorus is increasing in distribution in Argentina and that citizen science can be used to document the distribution of invasive alien plant species. Taking into account that the number of records obtained from herbarium collections was greater than the number of records from literature, this study shows the value of these as database that allows historical reconstructions. This study is part of a collaborative “Global South” alliance between Argentina, South Africa and New Zealand, determining the extent of I. pseudacorus invasion in the southern hemisphere and generating management strategies for its control.

黄旗鸢尾鸢尾科（鸢尾科）是一种新兴的多年生湿地植物，原产于古太平洋地区，已作为观赏植物散布于世界各地。在引入的范围内，它对天然和人工水体具有高度的侵袭性。目前，该物种难以管理，并继续传播，对环境造成重大影响。这项研究的目的是通过收集来自文献，馆藏，公民科学和实地调查的数据来评估阿根廷假单胞菌的地理范围。对植物标本室的收藏和文献进行了详尽的审查，并获得了包含通过公民科学获得的报告的数据库，并将其用于设计实地调查的路线。114个假单胞菌记录主要在潮湿和受干扰的地区获得。最早的记录可追溯到1931年和1933年，据报道的地点数量随时间逐渐增加。杂草有15个记录来自保护区，其中4个具有国际保护地位。这项研究表明，假单胞菌在阿根廷的分布正在增加，并且可以使用公民科学来记录外来入侵植物物种的分布。考虑到从植物标本馆收集的记录数量大于从文献收集的记录数量，本研究显示了这些作为可进行历史重建的数据库的价值。这项研究是阿根廷，南非和新西兰之间合作开展的“全球南方”联盟的一部分，该联盟确定了假单胞菌在南半球的入侵程度并产生了对其进行控制的管理策略。