ALKALOIDAL GLYCOSIDASE INHIBITORS IN NOCTURNAL AND DIURNAL URANIINE MOTHS AND THEIR RESPECTIVE FOODPLANT GENERA, ENDOSPERMUM AND OMPHALEA

Alkaloidal glycosides inhibitors (AGIs) were found to be present in adults of a nocturnal, cryptically-coloured representative of the subfamily Uraniinae, Lyssa macleayi, as well as a diurnal, aposematic uraniine, Alcides metaurus. The larvae of both species appeared to accumulate DMDP (2R,5R-dihydroxymethyl-3R,4R-dihydroxypyrrolidine) and HNJ (2,6-dideoxy-2,6-imino-D-glycero-L-gulo-heptitol) from their respective foodplants, Endospermum medullosum and Omphalea queenslandiae (Euphorbiaceae), which also contained DMJ (1,5-dideoxy-1,5-imino-D-mannitol) and DNJ (1,5-dideoxy-1,5-imino-D-glucitol). This is the first report of AGIs in the genus Endospermum. Another nocturnal uraniine moth, Urapteroides astheniata, was also found to contain DMDP and HNJ. Thus, within the Uraniinae, an apparent correlation between alternative nocturnal and diurnal habits and the utilization of either Endospermum or Omphalea as larval foodplants, does not seem to extend to qualitative differences in hostplant AGI chemistry or differences in the ability of the larvae to accumulate these compounds. The function of these biologically active compounds in uraniine moths is assesed.