Vibrational Duetting and Mating Behaviour of the Passion-Vine Hopper Scolypopa Australis (walker) (hemiptera: Ricaniidae)

The passion-vine hopper, Scolypopa australis (Walker) (Hemiptera: Ricaniidae), is an invasive pest of kiwifruit orchards in New Zealand. This species communicates via substrate-borne vibrational signals, but the behavioural functions of S. australis signals are only partly characterised and the roles played by vibrational signals and duetting in its mating and courtship are only partially known. Here, we performed an observational study using laser-Doppler vibrometry and video recordings to characterise the mating duet of S. australis, as well as its mate searching, orientation and close-range courtship behaviours. We characterise three new mating-related signals. We found that duetting underpinned the mating process, and was typically (but not exclusively) male initiated, with males initiating duets 79% of the time. Duets consisted of distinct localisation and close courtship phases, with characteristic male signalling patterns associated with each. Compared with male signals, female signal energy was very high in S. australis duets. Mating success was associated with consistent temporal patterns and shorter inter-syllable interval in male signals, with males dropping out of duets in most unsuccessful courtships. Additionally, we found that the distinctive 'wing-swinging' behaviour, which involves swaying the wings from side to side in a see-saw like motion, was associated with a trend towards increased orientation success from males towards females - 62% of wing-swinging males made correct orientation decisions, compared with 51% that were not wing-swinging. This behaviour was also involved in close-range courtship and precopula, and preceded the male nudging behaviour that initiated the final stages of courtship. These findings may serve as a foundation for developing potential mating disruption-based pest control regimes for this species.