Satin Lutestring

  • Satin Lutestring
    Satin Lutestring

Scientific name: Tetheella fluctuosa

June to early August. Local to south-east England and scattered locations further north and in Wales.

Generally larger than the Common Lutestring. Look for a small dark dash at the leading edge of the forewing near the wing tip. The outer half of the forewing is usually a paler colour but a darker form f. albilinea is darker.

The adults fly at night and are attracted to light.

The caterpillars can be found from late July to mid-September feeding at night and resting between two leaves spun flat together during the day. They overwinter as pupae in a delicate cocoon between leaves of the foodplant which fall to the ground with the leaves in autumn.

Size and Family

  • Family – Thyatridae
  • Medium Sized
  • Wingspan Range – 34-42mm

Conservation status

  • UK BAP: Not listed
  • Local (only found in some areas)

Caterpillar Food Plants

Birches and sometimes Alder (Alnus glutinosa)


Mature broadleaved woodland and wooded heath in south-east England


  • Countries – England, Wales and Scotland
  • Found locally in south-east England mainly in Kent, Sussex and Surrey. Northern records in west Wales, the Lake District, Cumbria and Inverness-shire. Rare in the Channel Islands.

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