''Perizoma affinitata'', the rivulet, is a species of

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...

of the family Geometridae. It was first described by James Francis Stephens in 1831 and it is found in most of Europe. Its wingspan is 24–30 mm and is characterized by the narrow white postmedian band of the forewing and especially by the dark hindwing, with only a narrow, divided white or whitish band. Northern and western Germany, and rather less extreme from England and according to

Otto Staudinger Otto Staudinger (2 May 1830 – 13 October 1900) was a German entomologist and a natural history dealer considered one of the largest in the world specialising in the collection and sale of insects to museums, scientific institutions, and indi ...

it is distributed in central and northern Europe and Romania. - ''rivinata'' Fisch.-Rossl. has the white on the forewing much extended and the hindwing broadly or almost wholly white. It belongs chiefly to northern or mountain districts, but sometimes occurs as an aberration with the type England, N. Norway, the Alps, Carpathians. - ''magistraria'' Trti. and Verity is larger, the forewing grey, not brown, but darker than in ''hydrata'' and with broader white band; hindwing greyish with double whitish band; underside like that of ''rivinata''. Terme di Valdieri, Maritime Alps.Prout , L.B. 1912–16. Geometridae. In A. Seitz (ed.) ''The Macrolepidoptera of the World''. The Palaearctic Geometridae, 4. 479 pp. Alfred Kernen, Stuttgart. The larva is rather powerful, pale pink with a dark head capsule and the dorsal side of the first body joint. The species is found in forest edges, hedges and on flower meadows. The larvae feed on '' Silene'' species, including ''

Silene dioica ''Silene dioica'' ( syn. ''Melandrium rubrum''), known as red campion and red catchfly, is a herbaceous flowering plant in the family Caryophyllaceae, native throughout central, western and northern Europe, and locally in southern Europe. It has ...

''. The larvae can be found from June to September. The species overwinters as a pupa.

References

External links

Rivulet at ''UKMoths''''Lepiforum e.V.''
Perizoma Moths described in 1831 Moths of Europe Taxa named by James Francis Stephens {{Larentiinae-stub