During brachyuran zoeal development, body somites, appendage setal counts and segment numbers either remain constant or show some increase. Setae and segments once gained are never lost during the zoeal phase except at metamorphosis to megalop. Changes in the relative timing of appearance of particular setae or in the expression of particular segmental articulations often coincide with abbreviated zoeal development. This study compares chaetotaxy and segmentation among three brachyuran families with differences in numbers of zoeal stages. Comparison against a reference zoeal developmental sequence (the outgroup) helped to identify some heterochronic processes such as acceleration or terminal delay of characters. Such characters may have phylogenetic significance.