Elachista herrichii is a moth

Moth

A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...

 of the Elachistidae

Elachistidae

| image = Elachista rufocinerea 2.jpg| image_width = 240px| image_caption = Adult Elachista rufocinerea,demonstrating its tiny size versus an aphid and a spider mite | regnum = Animalia| phylum = Arthropoda| classis = Insecta...

 family. It is found from the Baltic region

Baltic region

The terms Baltic region, Baltic Rim countries, and Baltic Rim refer to slightly different combinations of countries in the general area surrounding the Baltic Sea.- Etymology :...

 to the Pyrenees

Pyrenees

The Pyrenees is a range of mountains in southwest Europe that forms a natural border between France and Spain...

, Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 and Romania

Romania

Romania is a country located at the crossroads of Central and Southeastern Europe, on the Lower Danube, within and outside the Carpathian arch, bordering on the Black Sea...

.

The larvae feed on Agrostis

Agrostis

Agrostis is a genus of over 100 species belonging to the grass family Poaceae, commonly referred to as the bent grasses...

, Bromus pannonicus, Festuca arvernensis, Holcus

Holcus

Holcus is a genus of eight species of grasses, native to Europe, Atlantic Ocean islands, Africa and western Asia....

, Koeleria glauca

Koeleria glauca

Koeleria glauca is a grass species of the genus Koeleria. It grows in dunes and other sandy places. It is mainly distributed in eastern Central Europe, with its western outposts in the coastal dunes of Jutland and inland dunes in the Rhine Valley....

and Koeleria macrantha

Koeleria macrantha

Koeleria macrantha is a species of grass known by the common name prairie Junegrass. In the UK it is known as Crested hair-grass. It is native to much of North America, from Alaska to California, from northern Mexico to the Eastern United States...

. They mine

Leaf miner

Leaf miner is a term used to describe the larvae of many different species of insect which live in and eat the leaf tissue of plants. The vast majority of leaf-mining insects are moths , sawflies and flies , though some beetles and wasps also exhibit this behavior.Like Woodboring beetles, leaf...

 the leaves of their host plant. Just after hibernation, the larvae create mine which has the form of a fine, yellowish green shallow corridor in the basal part of the leaf. It then turns upwards and widens to the full width of the blade. The frass

Frass

Frass is the fine powdery material phytophagous insects pass as waste after digesting plant parts. It causes plants to excrete chitinase due to high chitin levels, it is a natural bloom stimulant, and has high nutrient levels. Frass is known to have abundant amoeba, beneficial bacteria, and fungi...

is scattered irregularly. Pupation takes place outside of the mine. They are yellow with a pale brown head. Larvae can be found from autumn to April or May and again from July to early August.