Butterfly of the Month - September 2024

The White-banded Plane or Common Aeroplane (Phaedyma shepherdi) has a wingspan of 55mm for the male and 57mm for the female. Together with the wing design created by the predominantly dark brown and white scale colours, it's the distinct gliding flight pattern that gives it away and provides the common name. 

The butterfly's life cycle starts with tiny pale greenish, deeply pitted eggs, almost round in shape. These eggs are laid singly, with the preferred locations being young plant growth. Once hatched, the larva builds a shelter by cutting out leaf pieces and affixing them on the leaf underside along the midrib. Dried  up leaves and larvae hiding behind them are brown. Camouflage provides protection here. 

The somewhat unusual shape of the larva, including pairs of spiny protusions, develops through the instar phases. Our images show the first and second as well as the fifth instar stages. It is assumed that the white spots on Phaedyma shepherdi's last three instars have the role of mimicry and are signaling to parasitic tachinid flies that eggs have already been laid. Tiny white patches can also be found on the pupa, presumably serving the same purpose. 

The White-banded Plane can be found along the edge of our (dry) rainforests, along waterways and gullies as well as vine thickets. 

In Brisbane, the butterfly's offspring feeds on a variety of native trees including Roughj-leaved Elm (Apananthe philippensis), Flame Tree (Brachychiton acerifolius), Lace Bark (Brachychiton discolor), Native Celtis (Celtis paniculata), Koda (Ehretia acuminata), also Milletia (Pongamia pinnata) which is not a local but is established in gardens. The woody vine Burny Bean (Mucuna gigantea) is also found among Phaedyma shepherdi's hosts. Don't be surprised if you see the larvae feed on the dreaded exotic Chinese elm (Celtis sinensis) too.

Images: SA - Sylvia Alexander; WJ - Wesley Jenkinson