Judy's case moth
My friend Judy sent me a photo of an unexpected bit of nature attached to her house. 'It's a cocoon', she said, 'isn't that cool' - knowing that I would be suitably thrilled too.
'It's a case moth', I emailed her. 'Keep an eye on it. You might catch it moving around, or with its head sticking out.' But Judy was not impressed. She doesn't like moths, was hoping it would turn out to be a beautiful butterfly.
|Metura elongatus, photographed by Arthur Bartholomew,|
part of a collection of zoological illustrations from Colonial Victoria
The cases of case moths are spun out of silk, and leaves, sticks and other materials are attached for camouflage. (Judy's case moth is obviously seriously challenged in relation to camouflage!)
There are several species, and which species Judy's belongs to is not known for sure, although it is probably Saunders' Case Moth, which is native to Australia. (Saunders' Case Moths like to use twigs). Even for an expert - which I'm not - it's hard to identify the various species. That's because even though each species has its own distinctive case, individual case moths use whatever materials they can find. This could be partly for convenience, but could also be a ploy to confuse interested humans.
Case moths spend most of their lives as caterpillars, about one or two years. During this time they never leave their cases. They drag them around when they feed and can close them up when they feel threatened. Even after they've turned into adult moths, females stay in their cases but males leave to search for females.
This post is dedicated to Judy, in an attempt to persuade her that moths are fascinating and important and complicated, even common ones like case moths.
|Saunders' Case Moth caterpillar in its case.|
Source: Museum Victoria