Genome sizes of Phasmatodea are close to that of orthopteran grasshoppers , which arose ~40.5 million years ago . However, Phasmatodea are much older, and many subgroups evolved in this order in the last ~200 million years . Chromosome numbers in this group are highly variable, and polyploidy is well documented in parthenogenetic taxa. Interestingly, in this group of insects, large genome sizes up to 8 picogram per haploid genome have been observed. The diploid chromosome number in stick insects ranges from 21 (male) or 22 (female), found in several species, up to 88 in Carausius furcillatus . Also, polyploid species with structurally diploid complements have been reported . Thus, many unique features of genome architecture and inheritance patterns can be observed in Phasmatodea. However, cytogenetic studies on them are principally hampered by high chromosome numbers (polyploidy) or poor chromosome morphology, or both.