A third active AKH is present in the pyrgomorphid grasshoppers Phymateus morbillosus and Dictyophorus spumans

The corpora cardiaca of the African pyrgomorphid grasshoppers Phymateus morbillosus and Dictyophorus spumans contain three adipokinetic hormones (AKHs): besides two already known AKHs, Phm-AKH-I and Scg-AKH-II (Gäde et al., 1996 [Gäde, G., Kellner, R., Rinehart, K.L., 1996. Pyrgomorphid grasshoppers of the genus Phymateus contain species-specific decapeptides of the AKH/RPCH family regulating lipid-mobilisation during flight. Physiol. Entomol. 21, 193-202]), a new AKH-III, denoted Phm-AKH-III, pGlu-Ile-Asn-Phe-Thr-Pro-Trp-Trp-NH(2), has been characterised. This is only the second AKH-III identified so far, thus, only three insect species - all of them grasshoppers - contain three active AKHs. Phm-AKH-III differs from Lom-AKH-III from the migratory locust, Locusta migratoria, only in position 2: isoleucine is present instead of leucine. The structure of the Phm-AKH-III was confirmed by synthesis, subsequent mass determination and reversed-phase high-performance liquid chromatography. The synthetic peptide also induced hyperlipaemia in D. spumans and L. migratoria.