First record and eradication of a non-European Hirschmanniella species in Germany
The NPPO of Germany recently informed the EPPO Secretariat of the first finding of a non-European species of Hirschmanniella on its territory. Hirschmanniella spp. (except H. behningi, H. gracilis, H. halophila, H. loofi and H. zostericola) are A1 quarantine pests for the EU.
Trace-forward activities linked to an outbreak in Denmark of Hirschmanniella caudacrena in aquatic plants of the genus Vallisneria (EPPO RS 2023/047) identified that small lots (10 plants in total, including V. spiralis 'Tiger', and Vallisneria 'Gigantea' (syn. V. nana)) from the infested site in Denmark had been delivered to Germany to a retailer in Schleswig-Holstein. The Vallisneria plants had been originally imported from Malaysia.
Part of the lot had already been sold to final consumers. All the remaining plants were removed from the basin and sampled. Only one adult nematode of a non-European Hirschmanniella species was detected. The species could not be identified but it was not a European species and, based on the finding in Denmark, it is considered that it is probably H. caudacrena. Aquatic plants of other genera in the same basin were sampled and tested negative. The water in the basin is constantly renewed. The outbreak is considered eradicated.
The pest status of Hirschmanniella caudacrena in Germany is officially declared as: Absent, pest eradicated.