Emperor Gum Moth: All You Need to Know – Simple & Comprehensive Guide

folder_openInsecta, Lepidoptera
comment10 Comments

The Emperor Gum Moth is a fascinating and beautiful insect, native to Australia and known for its striking appearance. As a large moth species, it boasts a vibrant mix of colors that catch the eye and has become a popular subject for collectors and enthusiasts alike.

During its life cycle, the Emperor Gum Moth goes through several stages including egg, larva, pupa, and adult. Each stage offers unique characteristics, making this moth an interesting study for those curious about the natural world. In addition, the caterpillars feed on Eucalyptus trees and other plants, displaying a strong connection with their environment.

As nocturnal creatures, these moths are primarily active during the evenings, flying and searching for suitable host plants to lay their eggs. With their beauty and intriguing life cycle, the Emperor Gum Moth is certainly a species worth learning more about.

Emperor Gum Moth Overview


The Emperor Gum Moth, scientifically known as Opodiphthera eucalypti, belongs to the order Lepidoptera, which includes all butterflies and moths. As a species under the family Saturniidae, it is commonly referred to as the Emperor Moth.


Emperor Gum Moths belong to the following taxonomic classification:

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Lepidoptera
  • Family: Saturniidae
  • Genus: Opodiphthera
  • Species: Opodiphthera eucalypti

Here is a brief comparison table of the two major types of Saturniidae:

Feature Emperor Gum Moth Cecropia Moth
Size 100-150mm wing span 110-160mm wing span
Color Brown/Grey Striking Red/Brown
Habitat Eucalyptus trees Mixed forest and urban environments
Range Australia North America

Key features of Emperor Gum Moths include:

  • Size: typically measure around 100-150mm in wing span
  • Color: brown and grey patterned wings
  • Habitat: primarily found on eucalyptus trees
  • Range: native to Australia

In general, Emperor Gum Moths are large, beautiful moths that belong to the Saturniidae family, which is also sometimes referred to as the Emperor Moth family. Originating from Australia and mainly thriving on eucalyptus trees, this unique species boasts brown and grey patterned wings spanning 100-150mm.

Physical Characteristics and Appearances

Caterpillar Stage

  • Body: In the caterpillar stage, the Emperor Gum Moth has a smooth body with tubercles.
  • Diet: Primarily feeds on Silver Birch leaves.

The Emperor Gum Moth caterpillar is characterized by its smooth body with small tubercles. Its diet primarily consists of Silver Birch leaves.

Cocoon and Pupa Stage

  • Cocoon: Spins a silk cocoon
  • Pupa: Transforms inside the cocoon

During the cocoon and pupa stage, the Emperor Gum Moth caterpillar spins a silk cocoon to encase itself. Inside the cocoon, it transforms into its adult form.

Adult Moth Stage

Male Adult Moth Female Adult Moth
Antennae: feathery Antennae: slightly less feathery
Wingspan: smaller Wingspan: larger
  • Eyespots: Both male and female moths have eyespots on their wings.
  • Colors: Vary in shades of brown, grey, and rust.

In the adult moth stage, the Emperor Gum Moth has both male and female individuals. Males have more feathery antennae compared to females and a slightly smaller wingspan. They both have eyespots on their wings which come in various shades of brown, grey, and rust.

Life Cycle and Metamorphosis

Eggs and Early Development

The Emperor Gum Moth (Opodiphthera eucalypti) begins its life cycle as eggs laid on eucalyptus leaves. The eggs are small, round, and pale green, which helps them blend in with their surroundings. During the summer months, these eggs hatch into tiny caterpillars ready to start feeding.

Caterpillar Growth

As the caterpillars grow, they go through a series of molts called instars. The initial color is green but it eventually develops into a vibrant coloration. Some characteristics of the caterpillars include:

  • Bright green color with white spots
  • Large, fleshy body
  • Orange head with black markings

Throughout the instars, the caterpillars consume eucalyptus leaves, rapidly growing in size. By the final instar, they can measure up to 12 cm in length.


Once the caterpillars reach their full size, they spin a cocoon. Inside, they undergo a pupal life stage, transforming into adult moths. This stage can last several weeks to months, depending on environmental conditions.

Adult Emergence

When the metamorphosis is complete, an adult Emperor Gum Moth emerges with a wingspan of 10-16 cm. The moth’s coloration is a mix of earthy brown and grey tones, helping it to camouflage. A comparison table of the different life stages:

Life Stage Duration Characteristics
Eggs 7-10 days Small, round, pale green
Caterpillars Up to 8 weeks Green, white spots, orange head, black markings
Pupation Weeks to months Pupal form, cocoon spun for protection
Adult Weeks to months Earthy brown and grey tones, wingspread 10-16 cm

Adult moths do not feed but focus on finding a mate and reproducing, completing the life cycle.

Distribution and Habitat


The Emperor Gum Moth (Opodiphthera eucalypti) is native to Australia, primarily found in the eastern states such as:

  • Queensland
  • New South Wales
  • Victoria

This moth species inhabits various habitats like:

  • Forests
  • Woodlands

Host Plants

Emperor Gum Moths rely on specific host plants, with eucalyptus being a key example.

New Zealand

The Emperor Gum Moth was introduced to New Zealand in the early 1930s. It has established populations in:

  • North Island
  • Nelson

Just like in Australia, these moths are found residing in:

  • Forests
  • Woodlands

Host Plants

In New Zealand, Emperor Gum Moths prefer eucalyptus and other Australian tree species.

Country Natural Habitat Example Host Plants
Australia Forests, Woodlands Eucalyptus
New Zealand Forests, Woodlands Eucalyptus, Australian tree species

Host Plants and Diet

Common Host Plants

Emperor Gum Moth caterpillars are known to feed on different types of host plants. Some common ones include:

  • Eucalyptus: Various species of eucalypt trees.
  • Pine: Pinus radiata is a common host.
  • Apricot: Prunus armeniaca trees.
  • Grapevines: Vitis vinifera and related species.
  • Pepper trees: Schinus molle trees.
  • Liquidambar styraciflua: Sweetgum trees.
  • Betula pendula: Silver birch trees.

Feeding Patterns

Caterpillars of the Emperor Gum Moth follow a typical feeding pattern:

  1. They start feeding on the foliage of their host plants.
  2. As they grow, they consume more leaves.


Although Emperor Gum Moth caterpillars consume a variety of host plants, the damage they cause is generally minimal. Some effects include:

  • Partial defoliation.
  • Mild damage to fruits, such as apricots and grapes.

However, healthy plants can often recover quickly from this damage.

Host Plant Damage
Eucalyptus Partial defoliation
Pinus radiata Minimal damage
Apricot Trees Mild fruit damage
Grapevines Mild fruit damage
Pepper Trees Partial defoliation
Liquidambar styraciflua Partial defoliation
Betula pendula Partial defoliation

Significance and Conservation

Threats and Concerns

Emperor Gum Moth (Opodiphthera eucalypti) faces certain challenges that affect their population:

  • Habitat loss: Deforestation and urbanization reduce available food sources and mating grounds.
  • Pesticides: Chemicals used in forestry can harm these moths during their larval stage.

The decline of these moths can impact the ecosystem as they play a crucial role as pollinators and as a food source for wildlife.

Role in Ecosystem

  • Pollination: Adult moths contribute to pollination, helping maintain plant diversity.
  • Food source: Caterpillars serve as prey for various birds and mammals, maintaining a balance within the forest ecosystem.

Conservation Efforts

Organizations like iNaturalist work to monitor and document insect populations, including Emperor Gum Moths. CSIRO research further helps to understand these moths and implement conservation strategies.

Comparison of Conservation Methods:

Method Pros Cons
Wildlife corridors Provides safe passage for moths between habitats Can be expensive to implement
Restricting pesticide use Reduces harm to moths May affect forestry productivity
Planting native trees Increases food and habitat availability May compete with other land use priorities

Key features of Emperor Gum Moths:

  • Large, striking appearance with a wingspan up to 150mm
  • Found throughout most of Australia, particularly in eucalyptus forests
  • Caterpillars feed on eucalyptus leaves

Characteristics of Emperor Gum Moths:

  • Two large eyespots on their wings deter predators
  • Bright green caterpillars with white stripes and short spines
  • Pupate inside a dense, oval-shaped cocoon


  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

    View all posts
  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

    View all posts
Tags: Emperor Gum Moth

Related Posts

10 Comments. Leave new

  • i saw the emperor moth sunning itself on a wall at work have photo but dont know how to do it she was big being groundsman i see lotss of different bugs this one aat belmont northshore auckland

  • Hola! I’ve been following your web site for some time now and
    finally got the bravery to go ahead and give you
    a shout out from Houston Tx! Just wanted to mention keep up the excellent work!

  • Hola! I’ve been following your web site for some time now and
    finally got the bravery to go ahead and give you
    a shout out from Houston Tx! Just wanted to mention keep up the excellent work!

  • Hi all
    My son has just found a gum moth very similar to the one image above, on our garage window.
    Is it meant to be in the forests of the central coast NSW?

  • Hi, Thanks for this page. In Warrandyte, Vic we found one 6″ long on a fence post under our Queensland Box Tree. It was identified by the president of our local Friends of the Warrandyte State Park. http://lepidoptera.butterflyhouse.com.au/anth/collesi.html For a week it wandered up & down the treated pine post and along the metal frame of the gate. It never went to the tree trunk just a metre away. At one point it seemed to be starting to spin a cocoon on the top of the post with a dead leaf. Eventually it kinda ‘pooped out’ colours faded & lay on the ground among leaf litter, hardly moving at all. When touched with a leaf it just curled up. We looked up details about the QLD Box tree and then cut lots of fresh twigs with leaves & put them & the caterpillar in a large shoe box with holes for air. It seems revived & now for a few days has been eating leaves & moving around different places in the box e.g.- upside down on a leaf, then nestled in a corner under leaves. Now after reading more, we’re thinking we should put a large-ish piece of bark in the box too & maybe it will spin a cocoon there. Every once & a while we’ve sprayed a little water on leaves @ one end of the box & also put the box outside when it was more warm & dry out there. Too many kids & dogs around to put it back out on the tree. Any suggestions for further nurturing in the shoe box? Thanks

  • Matthew Connors
    April 11, 2019 4:47 pm

    This one is definitely a Syntherata rather than an Opodophthera, and almost certainly S. escarlata. It depends a little on the exact location though because there are a couple of similar species

  • Hi, I remember this. We ended up having the University pick it up from us. I ended up in the local newspaper because it was a freak size caterpillar.


Leave a Reply

Your email address will not be published. Required fields are marked *

Fill out this field
Fill out this field
Please enter a valid email address.
You need to agree with the terms to proceed