The larval morphology of the western Palaearctic zygaenid species Aglaope infausta (Linnaeus, 1767) is described and figured in detail. Unlike other members of the zygaenid subfamily Chalcosiinae, the last instar larva of A. infausta has numerous secondary setae and a multitude of cuticular cavities that are devoid of openings. The other chalcosiine genera have primary setae and cuticular cavities with specialized openings through which a defensive secretion can be discharged. Imaginal characters, on the other hand, provide strong evidence for placing Aglaope in the Chalcosiinae.
Caterpillars of the poplar lutestring moth, Tethea or, construct leaf shelters that they defend against intruding conspecifics using a combination of vibratory signals and physical aggression. Staged interactions between a resident caterpillar and introduced conspecific were recorded with a video camera and laser vibrometer. Residents crawl towards the intruder and perform three behaviours: lateral hitting, pushing, and mandible scraping. Vibrations caused by mandible scraping result from the caterpillar repeatedly scraping opened mandibles laterally against the leaf surface in bouts lasting 1.16 ± 0.39 s, with an average of 4 ± 1 scrapes per bout. We propose that these scrapes function in leaf shelter defense against conspecifics for the following reasons: Mandible scrapes are produced only by residents; they are generated when a resident is approached by an intruder; the rate of scraping increases as the intruder approaches the shelter; and residents in all trials retain their shelters, with the intruder leaving the leaf within 127.9 ±104.3s from the beginning of the trial. The function and evolutionary origins of vibration-mediated territoriality in caterpillars are discussed. and Jaclyn L. Scott, Jayne E. Yack.