Studies of the pheromone communication and courtship behaviour were made on the caddisflies Rhyacophila nubila Zett., Rhyacophila fasciata Hag., and Agapetus ochripes Curt. (Insecta, Trichoptera). The chemistry of the secretions was analyzed by the gas chromatography (GC), electroantennography (EAD), mass-spectrometry (MS),and a new method of the Solid Phase Microextraction (SPME). Combinations of GC-MS, GC-EAD, SPME-GC-MS, SPME-GC-EAD provided the information on the pheromone components. Two new olfactory active volatiles, octanoic and octenoic acids, were found in the female secretion of Rh. nubila. Sticky trap tests showed male attraction neither to the native virgin female extract nor to any of previously found in this species alсohols and ketones. The racemic octenoic acid showed the distinct male attraction in these tests (at p=0.06). The octanoic acid found also in males might have repelling effect. The copulations accompanied by male wing fanning were observed for the first time in the laboratory; the relation of mating to feeding was found. Behaviours similar to the calling in moths and to the tremulation in scorpion flies were also observed. Similar behaviour was found in Rh. fasciata. Male antennae of A. ochripes responded to 14 female secretion compounds in the GC-EAD tests; the female antennal responds to the male extracts were also found. The spontaneous adult vibrational activity was recorded from A. ochripes in the laboratory experiments, though the copulations were absent. The method for recording of low intensity vibrations was developed and first records of vibrations were obtained for smallest caddisflies (Hydroptilidae). The records of the Trichoptera vibrations obtained previously for 7 species were digitized and the methods of noise reduction and analysis were developed. The waveforms and frequency spectra obtained for the first time showed the diversity of vibrational patterns in these species and the sex signal differences. The behaviour of Brachycentrus subnubilus Curt. and Silo pallipes F. were studied in the laboratory; the courtship communication patterns and the associated male to male aggressive behaviour were observed. Male agressive behaviour was discovered in Goeridae. No distinct male attraction to the female extracts was found in the field tests for these species. Peculiar substrate aggregation was found to occur in B. subnubilus. Presence of the inhibitors for the male pheromone attraction was found in females of Molanna angustata Curt. for the first time.
|Translated title of the contribution||Comparative investigation of the communication in caddisflies (Insecta, Trichoptera)|
|Publisher||Российский фонд фундаментальных исследований|
|Number of pages||451|
|Publication status||Published - 1997|