MALE-SPECIFIC VOLATILES FROM NEARCTIC AND AUSTRALASIAN TRUE BUGS (HETEROPTERA, COREIDAE AND ALYDIDAE)

Aeration and exocrine gland extracts were analyzed for three Coreidae and two Alydidae. Males of all the species studied emit volatile blend s that are probably pheromones, but sexual communication in these inse cts evolved differently. In the alydids, Riptortus serripes and Mirper us scutellaris, the metathoracic scent glands are sexually dimorphic, and the dimorphisms are expressed chemically. Secretions from the male alydids contain high concentrations of esters or alcohols [e.g., (E)- 2-hexenyl (Z)-3-hexenoate, (E)-2-hexenyl butyrate, and (E)-2-octenol], while females produce mainly acids and aldehydes [e.g., butyric and h exanoic acids, and (E)-2-hexenal]. In the coreids, Amblypelta lutescen s lutescens, Amblypelta nitida, and Leptoglossus phyllopus, the metath oracic scent glands are not sexually dimorphic, but male- and species- specific volatiles are released, apparently from cells in the cuticula r epidermis. The coreid male-specific volatiles are primarily monoterp enes and sesquiterpenes, including (-)-(3R)-(E)-nerolidol as the major component from A. lutescens lutescens (an Australasian species) and L . phyllopus (a Nearctic species). Only (+)-(3S)-(E)-nerolidol is commo nly found in plants so (E)-nerolidol from these coreids is environment ally unique because of its chirality.