Kingdom Animalia Subphylum Hexapoda Order Lepidoptera Scientific name Rheumaptera undulata | Phylum Arthropoda Class Insecta Family Geometridae Rank Species | |
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Similar Rheumaptera, Hydriomena furcata, Plemyria rubiginata, Eulithis testata, Argent and sable | ||
The Scallop Shell (Rheumaptera undulata or Hydria undulata) is a moth of the Geometridae family. It is found in most of the Palearctic ecozone and North America.
The wingspan is 25–30 mm. The ground colour of the forewings is pale.The cross-lines are darker, wavy, evenly spaced and numerous. The outer margin is pale brown with a scalloped fringe. The hindwings resemble the forewings but are paler.
There is one generation per year with adults on wing from the end of May to August in Europe.
The larvae feed on Betula (including Betula verrucosa and Betula pubescens), Vaccinium (including Vaccinium myrtillus and Vaccinium uliginosum) and Salix species (including Salix myrtilloides, Salix caprea, Salix aurita, Salix cinerea, Salix myrsinifolia and Salix phylicifolia), as well as Populus tremula, Populus balsamifera, Berberis vulgaris, Ribes alpinum, Spiraea salicifolia, Sorbus aucuparia, Elaeagnus commutata and Myrica gale. Larvae can be found in August and September. It overwinters as a pupa.