Lepidium didymum L., a new host plant for Pieris mannii (Mayer, 1851). Is this new host plant facilitating the species' rapid northwestern expansion?

The first confirmed use of Lepidium didymum (Brassicaceae) as a larval host plant of Pieris mannii (Mayer, 1851) is documented, based on oviposition and successful rearing in Belgium. The discovery of this new hostplant highlights the species’ ecological plasticity and may be a contributing factor regarding the ongoing expansion of the species across urbanised areas of north-western Europe.
The widespread presence of L. didymum in disturbed habitats may help sustain and extend future populations.