Phyllonorycter medicaginella 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 Gracillariidae

Gracillariidae

Gracillariidae is an important family of insects in the order Lepidoptera and the principal family of leaf miners that includes several economic, horticultural or recently invasive pest species such as the horse-chestnut leaf miner, Cameraria ohridella....

 family. It is found from Denmark

Denmark

Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...

 and Poland

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 to Belgium

Belgium

Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...

, the Alps

Alps

The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....

, Bulgaria

Bulgaria

Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...

 and Ukraine

Ukraine

Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

.

The larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

e feed on Medicago falcata

Medicago falcata

Medicago falcata is a plant species of the genus Medicago. It is native to the Mediterranean basin, but is found throughout the world. It forms a symbiotic relationship with the bacterium Sinorhizobium meliloti, which is capable of nitrogen fixation...

, Medicago lupulina

Medicago lupulina

Medicago lupulina is a summer annual or perennial plant usually considered a weed. It has a tap root. Like other legumes, it has three leaflets; its center leaflet is on a separate petiole...

, Medicago sativa, Melilotus alba, Melilotus officinalis

Melilotus officinalis

Melilotus officinalis, known as the yellow sweet clover, yellow melilot, ribbed melilot or common melilot is a species of legume native to Eurasia and introduced in North America, Africa and Australia.-Description:...

, Ononis spinosa

Ononis spinosa

Ononis spinosa is a plant belonging to the family Fabaceae, that is commonly known as spiny restharrow or just restharrow. It is found throughout much of Europe but seldom as far north as Scotland.-External links:*...

, Trifolium dubium

Trifolium dubium

Trifolium dubium, the Lesser Hop Trefoil or suckling clover is a plant in the family Fabaceae. This species is generally accepted as the primary plant to represent the traditional Irish Shamrock....

, Trifolium campestre and Trifolium repens. 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. They create a lower-surface tentiform mine that occupies an entire leaflet. Fully developed mines are strongly inflated and the leaflet is folded so closely that the mine is almost invisible from below. In this stage the larva has eaten all parenchyma above the mine, giving the mine a white colour. The pupa seems to lie freely in the cocoon without a cocoon, but the cocoon is in fact part of the inner lining of the mine. The frass is deposited in a clump in a corner of the mine, separated from the pupa by a partition.