Rosy maple moth
Becky Crew is a Sydney-based science communicator with a love for weird and wonderful animals. From strange behaviours and special adaptations to newly discovered species and the researchers who find them, her topics celebrate how alien yet relatable so many of the creatures that live amongst us can be.
If you’re going to be a moth, you might as well be a pretty one. The rosy maple moth (Dryocampa rubicunda) is one of the most beautifully coloured of the 11,000 moth species native to North America.
Nocturnal and relatively small, with a wingspan of up to 5.2 cm, its colouring ranges from bright yellow to pale cream, with varying shades of pink on the legs and wings. Like most members of the family Saturniidae, rosy maple moths are covered in a coat of dense fuzz, which helps them to pollinate flowers more efficiently.
As caterpillars, rosy maple moths are called green-striped mapleworms, because they develop a light green colouring soon after hatching. They also have two long and very distinctive black horns projecting from just behind their heads.
Very young mapleworms will feed on maple leaves in thick clumps before wandering off on their own to grow fat in solitude. Once they reach adulthood, the rosy maple moth no longer needs to feed, and instead uses the sensory receptors on its legs, antennae and near its mouth to find mates.
Rosy maple moth colours a mystery
It’s not known for sure why the rosy maple moth is coloured the way it is, but the pinks and yellows could serve as a warning to would-be predators, just as the large horns on the juveniles do. Many insects use bright colours to signal their unpalatability, which is known asaposematic behaviour, and field studies have found that rosy maple moths are not particularly favoured even amongst birds, and these are their top predators.
Alternatively, it’s been suggested that the rosy maple moth’s colouring gives it the appearance of flower parts, and so acts as a type of camouflage. This is certainly seen in the primrose moth (Schinia florida), another North American native that flaunts a similar bright pink and yellow colouring. In this case the benefits of this particular colour scheme are obvious, because the host plant of this species is the evening primrose, with varieties of bright yellow, white, and pink flowers with yellow centres.