Scientific name: Macrothylacia rubi
May to June. Britain and north and west Ireland. Large brown moth found on heathland, downland and coastal grassland.
This moth is named after its colouration; males are usually foxy-red/brown and females grey-brown. However, moths from cooler upland areas tend to be darker and less red than those from southern areas. Females are larger with considerably longer forewings and lack the feathered antennae of the males. This moth can be distinguished from similar species by the absence of a central white spot on the forewing. The male flies rapidly on sunny afternoons just above the ground searching for females which are nocturnal.
The large, hairy larvae can be seen from July to April on heathland, downland and coastal grassland. Fully grown caterpillars are up to 7cm in length. They have long brown hairs on the sides of the body and shorter dark orange hairs on the upper surface. Young caterpillars are darker brown with light orange bands along the body. The caterpillars hibernate fully grown, but emerge to bask in the spring sunshine before pupating in April.
Size and Family
- Family – Eggars (Lasiocampids)
- Large Sized
- Wingspan range – 44-62mm
- UK BAP: Not listed
Caterpillar Food Plants
Heathers, Bilberry (Vaccinium myrtillus) and Creeping Willow (Salix repens) on moors and heaths, Bramble (Rubus fruiticosus) and Meadowsweet (Filipendula ulmaria) in wet habitats and Salad Burnet (Sanguisorba minor) on downland.
Frequents a variety of grassland habitats including moorland, downland, damp meadows, sand dunes and open woodland.
- Countries – England, Wales, Scotland, Ireland
- Widely distributed throughout most of the British Isles except Orkney and Shetland.