Chrysaster hagicola 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 known from Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 (Hokkaidō, Honshū, Shikoku, Kyūshū), Korea

Korea

Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...

 and the Russian Far East

Russian Far East

Russian Far East is a term that refers to the Russian part of the Far East, i.e., extreme east parts of Russia, between Lake Baikal in Eastern Siberia and the Pacific Ocean...

.

The wingspan

Wingspan

The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...

 is 4.5-5 mm.

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 Lespedeza bicolor

Lespedeza bicolor

Lespedeza bicolor is a species of flowering plant in the legume family known by the common names shrubby bushclover, shrub lespedeza, and bicolor lespedeza. It is native to Asia and it is widely grown as an ornamental plant...

and Lespedeza cyrtobotrya. 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. The mine is flat and is found on the upper side of the leaf. It is linear at the first stage, and then suddenly broadens in the succeeding stage, finally becoming a large blotch covering up to nearly half of a single leaf. The mine is discoloured with yellow or brown on the upper side. Dark brown 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 plastered on the central part of the lower wall of the mine-gallery. In the first four instars the larva is flat and of the sap-feeding type, while in the last instar it is cylindrical and of the tissue-feeding type, but never feeds on the tissue consisting of lower parenchyma cells. At full maturity it cuts a semicircular hole at a corner of the mine through the upper epidermis, and then leaves the mine through the hole to pupate. It spins an oval or ellipsoidal cocoon at an edge of the contracted leaf.