The fungus Thekopsora minima is endemic in eastern North America and Japan and is not yet established in Germany. In 2002, it presumably was found for the first time in the EU in Southwest Spain but was wrongly identified as the endemic Pucciniastrum vaccinii (Naohidemyces vaccinii). Up to now T. minima is neither listed in the Annexes of the Dir. 2000/29/EC nor by EPPO. Thekopsora minima infests the highbush blueberry Vaccinium corymbosum which is native to North America and various Rhododendrons and Azaleae as well as various further genera of Ericaceae. Two Tsuga-species are alternating hosts. It can be assumed that due to suitable climate conditions Thekopsora minima is capable to establish outdoors in Germany. An establishment in South European EU-Member States would also be possible. Due to its damage potential for cultivated blueberries, Rhododendrons and other Ericaceae, Thekopsora minima poses a considerable phytosanitary risk for Germany and other EUMember States. Based on this risk analysis, it can be assumed that the pest is able to establish and cause considerable damage in Germany or other Member States. Thus measures on the control and prevention of introduction of this potential quarantine pest should be taken according to § 4a of the Plant Inspection Order. Thus the infestation must be controlled and eradicated according to § 4a of the Plant Inspection Order.