Undoubtedly the insect icon of the Daintree Rainforest on Cape York Peninsula, north of Cairns, Queensland is the large, flightless Peppermint Stick-Insect, Megacrania batesii (Kirby). I have written about this beautiful insect before and you can find details about its occurrence and history at this reference. It is such a nice insect that it deserves an additional blog.
The Peppermint Stick Insect, adult female Megacrania batesii; Phasmatidae; Platycraninae
It is a large insect with females measuring over 110 mm in length. They are beautifully coloured with blue, green and yellowish green predominating. The sticks reside within the midrib of their host-plant, Pandanus tectarius. They often "sun" during the day in a characteristic posture. They have excellent eyesight. When danger threatens, they scuttle back and forth in the midrib, often backing down to the base of the plant where the serrations along the margins of the plant offer considerable protection.
The Peppermint Stick-Insect has an odd geographical distribution. It is known from the Solomons, New Guinea and the Bismarck Archipelago. In Australia it has been found from Cape Tribulation south to Clump Point, south of Innisfail.
The egg-laying habits of the females may have the answer to its spotty distribution. Eggs accumulate in the detritus at the base of the leaves in the axils. During cyclones, clumps of Pandanus often become dislodged and float out to sea. Some may reach shore at a locality far removed from the source. Perhaps, this is how the Peppermint Stick-Insect gets around. But it does not explain why some plants are occupied and others are not.