May 6, 2026 – The golden-brown fern moth, a native of New Zealand and Australia, appears to have become an established exotic in Belgium, nature conservation group Natuurpunt said.
The moth, whose Dutch name `varenhobbit’ translates as fern hobbit, is not expected to be a pest species that behaves in an invasive way, the organisation said in a report on Wednesday. The golden-brown fern moth, or Musitoma nitidalis, was first observed in Belgium in the autumn of 2023 in the western town of De Panne, with introduction appearing to move from west to east, Natuurpunt said.
The arrival of the fern moth hasn’t been entirely unexpected, as the species was already spotted in southern England in 2009 and in Belgium’s northern neighbour the Netherlands in 2021. In the United Kingdom, where multiple occurrences suggest the moth may now be resident in some areas, the species is suspected to have originally been imported with tree ferns, according to UKMoths.
Credit: Donald Hobern, CC BY 2.0, via Wikimedia Commons
The golden-brown fern moth has managed to switch from Australian to European fern species without any problem, according to Natuurpunt. Common bracken or eagle fern, Pteridium aquilinum, is probably a suitable food plant, while in the Netherlands the moth’s caterpillars were found on the broad buckler-fern, Dryopteris dilatata, the organisation said.
Most of Belgium’s exotics originate from the Americas or Asia, and imported species from Australia and New Zealand are relatively scarce, Natuurpunt said, possibly due to differences in the natural environment and climate that make it harder for Australian species to maintain themselves.