SCENT GLAND COMPLEX OF ADULT COTTON STAINER BUG, DYSDERCUS INTERMEDIUS

The main components of the reservoir contents of the paired ventral metathoracic glands of adult Dysdercus intermedius are hex-2-en-1-al, oct-2-en-1-al, together with octanal, a monoterpene hydrocarbon C10H16, and acetaldehyde. Traces of two other compounds are often present. Water was identified but is considered to be an artifact. Material from females and from males is largely the same and is thought to function as a defensive secretion. It is less complex and more volatile than the defensive secretion from the posterior abdominal gland of fifth instar larvae. An explanation for this is discussed. Contrary to previous ideas, adults also possess three dorsal abdominal glands, corresponding to those present in larvae. The anterior two seem to be functional but the posterior one, associated with defence in the larvae, is not. © 1969.