Haplopodous Diplopods: A New Type of Millipede Body Construction Discovered in Cambalopsid Juveniles (Diplopoda,Spirostreptida)

Abstract Early juvenile stadia are described in four species of family Cambalopsidae. Hypocambala helleri Silvestri, 1897, and H. anguinea (Attems, 1900) show normal relationships between numbers of podous and apodous rings, and numbers of leg-pairs. Glyphiulus granulatus (Gervais, 1847) and Trachyiulus tjampeanus (Attems, 1903) have a deviating stadium (probably stadium III) in which most of the podous rings (10–13 rings in G. granulatus, 19 rings in T. tjampeanus) have only one leg-pair. No trace of the anterior leg-pair, nor of its sternum, could be found in these rings. At the moult to the next stadium (?IV), the normal, diplopodous condition is restored. The term haplopodous diplopods is suggested for the deviating juveniles of G. granulatus and T. tjampeanus. The haplopodous condition creates potential problems for palaeontology and indicates a closer relationship between Glyphiulus and Trachyiulus than reflected in current classifications.