The larval caterpillar Pseudosphinx tetrio L. is a species that feeds specifically on plants belonging to the family Apocynaceae. The genus Allamanda includes many shrubs or flowering trees which are grown throughout the tropical regions and are well known due their several biological properties. This work explores the interaction between the caterpillar and this plant using several analytical techniques such as thin layer chromatography, nuclear magnetic resonance spectroscopy, high performance liquid chromatography coupled with mass spectrometry and cyclic voltammetry. Further, a multivariate data analysis was performed in attempt to obtain better insights regard the samples.
The results point out the similar profile between the health and herbivore Allamanda cathartica L.’s leaves and the caterpillars’ faeces. The similar analytical profile between the leaves of A. cathartica and the faeces of P. tetrio, as well as the difference with the caterpillar’s bodies suggest a selective excretion of compounds by the caterpillar. These compounds found selectively in the faeces (and not in the body) can explain that P. tetrio can feed this toxic Apocynaceae species.