Metriochroa fraxinella
Encyclopedia
Metriochroa fraxinella is a moth
of the Gracillariidae
family. It is known from Japan
(Honshū, Kyūshū and the Ogasawara Islands).
The wingspan
is 5.2-8.2 mm. There are at least two generations per year in temperate Japan (Honsyu and Kyusyu), because adults are on wing in summer (from June to July) and in autumn (from late September to early October).
The larva
e feed on Fraxinus species (including Fraxinus sieboldiana), Ligustrum japonicum
and Ligustrum micranthum. They mine
the leaves of their host plant. The mine is found under the upper cuticle of the leaves. It is narrowly linear, very long, irregularly curved, and sometimes occupying the whole leaf surface. It is whitish with a brownish central line of frass
. Pupation takes place within the mine in a pupal chamber that is located at the end of the mine. This chamber is ellipsoidal, with a strongly swollen lower side and a wrinkled upper side.
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...
(Honshū, Kyūshū and the Ogasawara Islands).
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 5.2-8.2 mm. There are at least two generations per year in temperate Japan (Honsyu and Kyusyu), because adults are on wing in summer (from June to July) and in autumn (from late September to early October).
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 Fraxinus species (including Fraxinus sieboldiana), Ligustrum japonicum
Ligustrum japonicum
Ligustrum japonicum is a species of Ligustrum native to central and southern Japan and Korea....
and Ligustrum micranthum. 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 found under the upper cuticle of the leaves. It is narrowly linear, very long, irregularly curved, and sometimes occupying the whole leaf surface. It is whitish with a brownish central line of 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...
. Pupation takes place within the mine in a pupal chamber that is located at the end of the mine. This chamber is ellipsoidal, with a strongly swollen lower side and a wrinkled upper side.