Classification of simvastatin induced-phenotypes at different developmental times. Embryos were treated at 6 hpf and fixed at 24 hpf (a–d) and at 11 hpf and fixed at 30 hpf (e–h). For each time point, a representative image of each class of embryonic effect is shown over the parameters used to classify them (tail length, yolk length, and CI: Curvature Index). Zebrafish embryos were treated with the following simvastatin concentrations: Control (a, e): no simvastatin; Normal phenotype (b, f): up to 0.3 nM; Mild phenotype (c, g): from 3 to 6 nM; Severe phenotype (d, h): from 0.375 to 1 μM. Scale bar corresponds to 100 µm