Miller?s Nettle-tap Prochoreutis myllerana
Reaching a wingspan of 10 to 14 mm only Miller?s Nettle-tap is a very small moth indeed. It is a dark brown species with silvry white scales scattered all over the central part of the wing. Near the edges there are silvry white spots. The fringe is white, the antennae are black with numerous white rings. But this animal is extremely variable and may be greyish, or beautifully marked in various colours. The silvry white scales reflect the sunlight, making it difficult for predators to locate the exact spot where the moth is present. This only works during daylight and thus all Metalmark Moths are on the wing during daylight.
There are probably two or three breeds in a year and they overlap. This means that adult moths, caterpillars and eggs may be seen at the same time: from May to September. After hatching the young larvae mine the lower leaves of the host plant. Later on they spin a thread to roll up just one leaf and live inside this rolled up leaf. In the last instar they may spin two or more leaves together. From October the larvae become inactive and overwinter as almost full grown caterpillars. The first fresh adults appear in May. Only two host plants are known: Common Skullcap (Scutellaria galericulata) and Lesser Skullcap (Scutellaria minor).
Miller's Nettle-tap is uncommon all over the British Isles and Ireland. Locally it may be numerous though. It has a very large territory: all of Europe, Russia, China, Korea and Japan.
There is a look-a-like, which is very rare in Western and Central Europe, for it is a Mediterranean species mainly: Prochoreutis sehedestediana. It is hard to tell the two species apart. Usually the area with scattered silvry white scales is larger in Prochoreutis sehedestediana. It is very small in the animal in the picture and so we can be sure it is Miller's Nettle-tap. But in other specimens this is less obvious and some overlap exists. In those cases examining the genitals is the only option to tell the two species apart.
