The Processionary Caterpillar (Ochrogaster lunifer), also commonly known as the Itchy Grub, is particularly interesting to watch as they create a single line of caterpillar following each other.

Although they can be seen following each other along the ground in daylight, the caterpillars usually shelter communally in a bag nest made of silk, excrement, shed skins, and other debris at this time of day. In Central Australia, these bags of silk can often be seen high in the branches of the trees they feed on (usually acacia and Grevillea striata (beefwood tree). They can also be found nested at the base of shrubs and trees (which may indicate that there may be others species of these caterpillars, genus Ochrogaster).

Common name
Itchy Grub, Processionary Caterpillar, Bag Shelter Moth (which is the adult form of the caterpillar larva).

Images © Greg Sully


  • Scientific classification
  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Lepidoptera
  • Family: Notodontidae
  • Subfamily: Thaumetopoeinae
  • Genus: Ochrogaster
  • Species: O. lunifer
  • Binomial name: Ochrogaster lunifer

Footnote & References

  1. ‘Itchy grub’ link to bush medicine, by Emma Sleath, 4 April 2013, ABC Local, https://www.abc.net.au/local/stories/2013/02/13/3689704.htm