In this study, the morphology and ontogeny of Chamobates subglobulus (Oudemans, 1900) and Euzetes globulus (Nicolet, 1855) are compared. The adults of both species are at the first glance strikingly similar to each other, except for the body size, because the latter species is larger than the former species. These adults are ball-shaped, dark-brown or black, with well-developed prodorsal lamellae, relatively long prodorsal setae ro, le and in, 10 pairs of notogastral setae or their alveoli and octotaxic system of porose areas, but in E. globulus the notogastral setae are tiny, whereas in Ch. subglobulus these setae are lost and only their alveoli remain. Moreover, the former species has 7–8 setae on epimere IV (neotrichy occurs), whereas the latter species has three setae. In contrast, the juveniles of both species differ distinctly from each other and from the adults. They have long prodorsal setae, but Ch. subglobulus is more elongated and has long gastronotal setae, whereas E. globulus is rather ball-shaped, with short gastronotal setae. The juveniles of both species have a humeral organ, at least in the nymphs, but in Ch. subglobulus this organ is placed near the posterolateral corner of the prodorsal shield, as in most species of Ceratozetoidea, whereas in E. globulus it is located lower, in the sejugal plane, above the level of insertion of leg II, as in the juveniles of Galumnidae. However, the nymphs of E. globulus lack octotaxic system of porose areas that occurs in the Galumnidae. In E. globulus, the neotrichy of setae occurs on the epimere IV of the tritonymph and adult, whereas Ch. subglobulus has three pairs of setae there. The systematic position of E. globulus in Brachypylina is discussed.