We present a developmental study focusing on the development of coloration patterns in a subgroup of Neotropical cichlids, the subfamily Cichlasomatinae. Based on the presented coloration ontogenetic series of 40 species we show that developmental information is a necessary prerequisite for any serious attempts in understanding adult coloration patterns. The center of our contribution is a detailed description of coloration ontogenies in a selected sample of cichlids and their discussion in a much wider taxonomical sampling. The pigmentation pattern ontogeny is specifically used to determine developmental homology of individual vertical bars. Early ontogeny is documented from the onset of the free-swimming period, which is also used as a point of reference for possible heterochronic shifts as presented here. A single universal process is responsible for the transformation of longitudinal melanophore migration lines into vertical bars, which form the dominant elements of adult coloration of most cichlids. Adult vertical bars vary interspecificaly in their numbers, whereas their ontogenetic precursors are stable in number across all surveyed species. The diversity of adult barring patterns is produced by differential fusions of a conserved number of developing bars, from which the different taxon specific numbers of adult bars develop. The possibility of determining individual homology of cichlid vertical bars is a prerequisite for the use of coloration pattern characters in cichlid phylogenetic studies. Several ontogenetic characters are formulated as synapomorphic at various systematic levels.