Abstract

The morphological ontogeny of Amerus polonicus Kulczynski, 1902 is described and illustrated, based on the individuals from laboratory culture. The juveniles of this species are unpigmented, with punctated integument. The larva has 11 pairs of gastronotal setae, including h2, the nymphs have 12 pairs. The nymphs are quadrideficient and eupheredermous, i.e. they carry the exuvial scalps of previous instars on the gastronotum, using mainly the inward curving setae la and lm to protect the exuvial scalps against loss. In all juveniles, seta d is present on all femora, genua and tibiae, and setae d on femur I and ft" on tarsus I are very long. All tarsi of juveniles are beaded, with long, thin distal parts. In the adult, seta d is lost on genua and tibiae I and II, but is retained on genua and tibiae III and IV.