We present the karyotype of the Australian harvestman Austropurcellia arcticosa (Cantrell, 1980) (Arachnida: Opiliones: Cyphophthalmi: Pettalidae), which represents the first cytogenetic analysis of Opiliones from the Australasian ecozone. The diploid complement comprised 30 chromosomes, as reported earlier for two other species of Cyphophthalmi in the family Sironidae, but with a predominance of biarmed chromosomes in A. arcticosa.
Morphologically differentiated sex chromosomes were not observed. The course of meiosis is described in the suborder Cyphophthalmi for the first time.