Marsh Mallow Moth

    Scientific name: Hydraecia osseola

    Flies at night in late August to early October and comes to light. Occasionally wanders from breeding sites.


    • Medium Sized 
    • Wing Span Range (male to female) - 40-50mm

    Conservation status

    • UK BAP: Priority Species
    • Red Data Book

    Caterpillar Description

    Overwinters as an egg. The larva feeds in the stem and roots from May to July, pupating underground.

    Particular Caterpillar Food Plants

    Marsh-mallow (Althaea officinalis)


    • Countries – England
    • Romney Marsh in Kent and on the East Sussex border, also the Medway Valley, Kent. Historically also recorded near Hailsham, East Sussex.
    • Distribution Trend Since 1970’s = Britain: Stable


    Grazing levels and along the banks of brackish rivers.