Biologically active peptides of the tachykinin and bombesin families occurring in the skin of the Australian leptodectylid frog Uperoleia rugosa were isolated in pure forms and their structures were determined. Uperclein-like peptide 1 was identified, as expected, as authentic uperolein; uperolein-like peptide 2 was found to have the sequence Pvr-Ala-Asp-Pro-Lys-Thr-Phe-Tyr-Gly-Leu-Met-NH, and may be considered a Lys5, Thr6physalaemin. Bombesin-like peptide 1, in its turn, was identified as Glu(OEt)2-litorin, and bombesin-like peptide 2 as authentic litorin. Uperclein and litorin had previously been identified in Uperoleia rugosa and Litoria aurea, respectively; the other two peptides are new. Glu(OEt)2-litorin and Lys5, Thr6-physalaemin appear to have biological activities very similar to those of Glu(OMe)2-litorin and physalaemin (or uperolein), respectively.