Hellula undalis
Encyclopedia
The Cabbage Webworm or Old World Webworm (Hellula undalis) is a moth
of the Crambidae
family. It is a widespread species which is found from Europe
across Asia
to the Pacific. It was first described from Italy
.
The wingspan
is about 18 mm. Adult moths have fawn forewings, each with sinuous pale lines and a kidney-shaped mark. The hindwings are a uniform grey darkening at the margins.
The larvae feed on a wide range of plants, mainly of the Brassicaceae
family. Recorded foodplants include broccoli, crucifers, head cabbage, Chinese cabbage, spoon cabbage, daikon radish, horseradish, mustard, radish and turnip. It is considered a serious agricultural pest. The larvae initially bore into the stem of growing shoots, later instars mine
the leaves and leaf stems. It makes a web of silk around the feeding area which accumulates frass
. The caterpillar is 12-15 mm long and is whitish with pinkish-brown longitudinal stripes.
Pupation occurs within this silken shelter. The pupa is formed in a loose cocoon of webbed-together particles of soil or other matter and is about 8 mm long, shining pale brown with a dark stripe on the back.
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 Crambidae
Crambidae
The Crambidae are the grass moth family of Lepidoptera . They are quite variable in appearance, the nominal subfamily Crambinae taking up closely folded postures on grass-stems where they are inconspicuous, while other subfamilies include brightly coloured and patterned insects which rest in...
family. It is a widespread species which is found from Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
across Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
to the Pacific. It was first described from 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...
.
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 about 18 mm. Adult moths have fawn forewings, each with sinuous pale lines and a kidney-shaped mark. The hindwings are a uniform grey darkening at the margins.
The larvae feed on a wide range of plants, mainly of the Brassicaceae
Brassicaceae
Brassicaceae, a medium sized and economically important family of flowering plants , are informally known as the mustards, mustard flowers, the crucifers or the cabbage family....
family. Recorded foodplants include broccoli, crucifers, head cabbage, Chinese cabbage, spoon cabbage, daikon radish, horseradish, mustard, radish and turnip. It is considered a serious agricultural pest. The larvae initially bore into the stem of growing shoots, later instars 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 and leaf stems. It makes a web of silk around the feeding area which accumulates 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...
. The caterpillar is 12-15 mm long and is whitish with pinkish-brown longitudinal stripes.
Pupation occurs within this silken shelter. The pupa is formed in a loose cocoon of webbed-together particles of soil or other matter and is about 8 mm long, shining pale brown with a dark stripe on the back.