Defensive secretions of New Zealand tenebrionids V. Presence of methyl ketones inUloma tenebrionoides (Coleoptera: Tenebrionidae).

The defensive secretion ofUloma tenebrionoides (White, 1846) contains benzoquinone, 2-methylbenzoquinone (toluquinone), and 2-ethylben-zoquinone as in other tenebrionids, together with 2-methoxyphenol, pentadecene, heptadecene, 2-pentanone, 2-pentadecanone, 2-heptadecanone, heptadec-10-en-2-one and (Z)-nonadec-10-en-2-one. The latter four methyl ketones have not previously been identified in tenebrionid beetles, and the unsaturated ketones are novel arthropod chemicals.

Toxicity of nitro compounds fromLotus pedunculatus to grass grub (Costelytra zealandica) (Coleoptera: Scarabaeidae).

Crude extracts of root of the forage legumesLotus pedunculatus andCoronilla varia (crownvetch) were toxic when administered orally to 3rd instarCostelytra zealandica larvae. A group of 3-nitropropanoyl-D-glucopyranoses was isolated from active fractions of the crude extracts. These toxins, some of which were already known fromC. varia, have not previously been reported fromL. pedunculatus. The compounds were present in root tissue of this species at a concentration of about 1% dry weight. They include the triester karakin and the diesters coronarian and cibarian, all of which were toxic to larvae ofC. zealandica at levels which could account fully for the activity of the crude extracts.

Ethyl decanoate as a major component in the defensive secretion of two new zealand aleocharine (staphylinidae) beetles-Tramiathaea cornigera (broun) andThamiaraea fuscicornis (broun).

The defensive secretions of bothTramiathaea cornigera andThamiaraea fuscicornis contain undecane, toluquinone, ethyl decanoate and smaller amounts of other esters. The presence of esters particularly ethyl decanoate as a major component sets these two beetles apart chemically not only among the staphylinids but also within the subfamily Aleocharinae.

Defensive secretions of new zealand tenebrionids: : I. Presence of monoterpene hydrocarbons in the genusArtystona (Coleoptera, Tenebrionidae).

The defensive secretions of four species of the genusArtystona endemic to New Zealand differ from those of other tenebrionids in that they contain α-pinene and limonene, as well as the more characteristic quinones and alkenes. Adults and larvae ofA. obscura, A. erichsoni, A. rugiceps, andArtystona sp. feed on the lichenParmotrema reticulatum (Taylor), but the terpenes are not sequestered from it. The defensive secretions of the four species show some interspecific variation.