Fluorescence in pumpkin toadlets. Ethanol-preserved specimens of Brachycephalus pitanga (a–c), B. ephippium (e–g) and Ischnocnema parva (k), and live Ischnocnema parva (i,j) photographed in natural light (a,e,i) and showing fluorescence under UV illumination using two Fluotest Forte UV (λexcitation centred around 365 nm; b,f,j) and a laboratory UV light source (λexcitation = 365 nm) and an emission filter centred around 472 nm and 30 nm wide, thereby eliminating reflectance of all visible light (c,g,k). Note that the absence of fluorescence in I. parva results in a completely dark image (k). Computerized micro-tomography (µCT) reconstructions (c,h,l) show the correspondence between fluorescent patterns and bone structure in B. pitanga (d), B. ephippium (h) and I. parva (l). Photographs taken by L.C. and S.G. (a,b,e,f,i,j) and P.G., M.T. and S.G. (c,g,k).