Cuticular hydrocarbons on elytra of the Diaprepes root weevil Diaprepes abbreviatus (L.) (Coleoptera: Curculionidae)

Abstract

Abstract 1 External gland openings and associated structures on the elytra of teneral and mature Diaprepes root weevils, Diaprepes abbreviatus (L.), were elucidated by scanning electron microscopy (SEM).2 There were clear differences between teneral, callow adults and fully mature adults. In the field, teneral adults remain in the pupal chamber in the soil until sclerotization of the cuticle is complete or nearly so.3 Phenotypic variation of the elytra in this species consists of varying patterns and coloration of scaled intervals between a variable number of raised ridges devoid of scales. In addition to being thinner and lighter in colour than fully mature adults, the elytra of teneral adults were devoid of waxy hydrocarbon secretions.4 External gland openings at the base of each scale were observed on teneral elytra and mature elytra washed with methylene chloride.5 SEM evidence to document the production of waxy filaments by these glands and partial characterization of these by gas chromatography and mass spectrometry are presented.