Ailanthus Webworm Moth: All You Need to Know – Quick Guide for Curious Minds

The Ailanthus Webworm Moth is a fascinating insect with unique characteristics that set it apart from other moths. Its vibrant colors and distinctive patterns make it easy to identify. Found in various parts of the United States, this moth plays an interesting role in its ecosystem. Originating from the tropics, the Ailanthus Webworm Moth (Atteva aurea) can now be spotted down the far north. The adults are known for their striking orange forewings adorned with white spots and black outlines, oftentimes resembling tiny flower patterns. Their larvae feed the Tree-of-Heaven (Ailanthus altissima), which is native to China. Quick Facts:

• Size: About half an inch in length
• Color: Orange forewings with white and black details
• Food Source: Tree-of-Heaven leaves (for larvae)
• Distribution: United States, particularly in South Florida

Even though the majority of Ailanthus Webworm Moths are found in southern Florida and other tropical areas of North America, their adaptable nature is helping them to spread to new areas. On one hand, the moth’s larvae help control the population of an invasive tree species, but on the other hand, a higher moth population could lead to a decline in native plants or have other unforeseen consequences.

Ailanthus Webworm Moth Overview

Atteva Aurea

The Atteva aurea, commonly known as the Ailanthus Webworm Moth, is a small, colorful insect. Notable traits of this moth include:

• Long, thin body
• Orange forewings with white spots outlined in black
• Curved mouthparts (labial palps)
• Tufted head scales
• Filamentous antennae

This moth has a wingspan of around 1/2 inch and often holds its wings tight against its body when not in flight.

Ermine Moth

The Ailanthus Webworm Moth is an Ermine Moth, belonging to the family Attevidae. Some characteristics of Ermine Moths include:

• Bold colored wings
• Striking patterns
• Small size

Here’s a comparison table of the two entities:

Life Cycle

Eggs

The life cycle of the Ailanthus Webworm Moth begins with the female moth laying eggs, generally on the underside of leaves¹. Hatching occurs within 2 weeks and marks the start of the caterpillar stage¹.

Caterpillars

The caterpillars of the Ailanthus Webworm Moth are slender and colored brown to almost black and may have four white dots on each segment. They feed on Ailanthus tree leaves, which is how they got their name.

Pupa

After the caterpillar stage, the Ailanthus Webworm Moth enters the pupa stage¹. This typically occurs in the soil, where the caterpillar forms a cocoon for metamorphosis¹. The pupa stage takes place throughout the winter months¹.

Adult Moth

The adult Ailanthus Webworm Moth is a small insect that is characterized by its long, thin body and its unique wing pattern². The adult moths emerge in the summer and are usually seen around late June and early July¹. To put it in a nutshell, the Ailanthus Webworm Moth goes through four stages in its life cycle:

• Eggs: laid on the underside of leaves, hatch within 2 weeks¹
• Caterpillars: slender, brown to black, with possible white dots²
• Pupa: occurs in soil, during winter months¹
• Adult Moth: emerges in summer, with distinctive orange and white spotted wings⁴

Habitat and Distribution

Host Plants

The Ailanthus Webworm Moth is primarily associated with the Tree of Heaven, an invasive species from China. This moth also feeds on other trees such as the Paradise Tree (Simarouba glauca), and Simarouba amara.

• Common host plants:
  • Tree of Heaven
  • Paradise Tree
  • Other Simarouba species

Geographical Range

The Ailanthus Webworm Moth is native to tropical areas, including Costa Rica and Southern Florida. However, it has expanded its range in response to the spread of its primary host, the Tree of Heaven. The moth can now be found throughout North America, particularly in Eastern Canada and the United States. Urban areas and nurseries with Ailanthus trees are hotspots for Ailanthus Webworm Moth populations.

• Native range:
  • Southern Florida
  • Costa Rica
• Expanded range:
  • North America
  • Eastern Canada
  • Urban areas with Ailanthus trees

Comparison Table:

Pollination and Ecological Role

Pollinator Interactions

The Ailanthus Webworm Moth also plays a key role in pollination. As they gather nectar from flowers, they inadvertently transfer pollen between plants, supporting plant reproduction. Some key points about their role as pollinators include:

• Active during the day and night.
• Attracted to pale or white flowers with fragrance.

Invasive Species Impact

As mentioned above, the moth’s caterpillar stage feeds on the foliage of invasive Ailanthus trees, which can help in controlling their spread. Here’s a quick comparison of the pros and cons of this relationship:

Conclusion

In summary, the Ailanthus Webworm Moth is an interesting creature with both pollination and ecological roles, benefiting the environment by controlling invasive tree species while also serving as a valuable pollinator.