Sunday, June 19, 2011
Batwing Moth (Chelepteryx collesi)
Bogong Moth (Agrotis infusa)
Newcomers to Gippsland may sometimes be startled at night by a light tapping on their windows, especially in the autumn, only to find that the noise-maker isn’t a pesty neighbour or prankster, but a big fat moth. In some cases the would-be intruder might be the famous Bogong Moth (Agrotis infusa), but it could also be a member of some larger moth species that make their presence known in our region when the autumn nights begin to cool: the Emperor Gum Moth (Opodipthera eucalypti) and the Giant Anthelid or Batwing Moth (Chelepteryx collesi). The three species are easily distinguished. Bogong Moths have a mottled dark grey or brown and white pattern with some scalloped lines on their wings, which only measure 3 to 5.5cm when spread. Emperor Gum Moths are a dull red or orange colour with a single spot on each wing, which span between 8 and 13cm. And Batwing Moths have a more distinctive brown patterning that includes some pronounced scalloping, their wings spanning up to 16cm. The first are found in temperate regions of southern Australia, while the other two are found all over eastern Australia; and whereas Bogong Moths will feed on crops, their larger cousins prefer the foliage of trees, including eucalypts, pepper trees and silver birch. The Bogongs belong to a moth family called Noctuidae, which has more than 25,000 species spread across the globe, while the Emperors belong to the Saturniidae family, numbering over 1,000 species worldwide, and the Batwings are part of the Anthelidae, which has fewer than 100 species, all confined to Australia and New Guinea. One interesting fact about both of the bigger moths is that the tongues of the fully matured adults are greatly reduced, thereby preventing them from feeding. There are numerous other moth species around Mirboo North, which is not surprising given that Australia has a huge variety – 20-30 thousand species, compared, for example, to 11-12 thousand in North America and about 2400 in the UK.