The ontogeny of morphological traits in three species of Galumnidae (Acari: Oribatida)

Abstract

The ontogeny of morphological traits in three members of the oribatid mite family Galumnidae – Acrogalumna longipluma (Berlese, 1904), Allogalumna alamellae (Jacot, 1935) and Galumna alata (Hermann, 1804) – is described and illustrated for the first time and compared with the literature. The juveniles of all species have macrosclerites, microsclerites and a humeral organ, but particular species differ in body size, the length of c-series setae, pattern of integument in anterior part of gastronotum and shape of solenidion ω1 on tarsus I. Their larvae additionally differ by the shape of setae in and dp, presence of transverse furrow on the gastronotum and the length of prodorsal seta in, whereas the nymphs differ by the size of circumgenital macrosclerite and presence of adanal macrosclerite. The adults of these species differ mainly by the presence of lamellar ridge L on the prodorsum and location of seta le, shape of porose area Aa, presence of median pore mp on the notogaster and shape of sensillus. The morphology of juveniles of three species of Pilogalumna Grandjean, 1956 suggests that the presence of transverse furrow in larva and absence of circumgenital macrosclerite in nymphs have probably generic value.