The Australian noctuid moth, Speiredonia spectans

Thsi moth shares its usual subterranean day roosts (caves and abandoned mines) with insectivorous bats, and not usually hares.

Granny’s Cloak Moth, noctuid Speiredonia spectans,_w

Granny’s Cloak Moth, noctuid Speiredonia spectans

Moths respond to ultrasound with evasive movements using their ‘ears’, tympanic organs located on the thorax . They fly away from the source of the sound and will dive when the sound is too loud and close. I saw this behaviour when I foolishly freed this beautiful moth from the house in daylight from the top floor. It fluttered around our large windows trying to reach somewhere darker, and from nowhere a Brush Wattle bird swooped, but the moth dived down and away.

Moth with hare

Moth with hare

The moth’s ears have two sensory cells with identical tuning curves, but different sensitivity thresholds differ which provide sound localisation. The moth can even change its own sensitivity if it is preyed upon by bats with different echolocating calls. This particular noctuid moth, Speiredonia spectans adapts its acoustic sensitivity according to the characteristics of the call of the bat inside the cave with them.