[4] When the males have a diploid number of chromosomes they are termed parahaploids as the paternal genes are not expressed at all.
[2] The paternal chromosomes are inactivated by heterochromatization in all the cells at an early embryonic stage.
In a few other species all the cells in an adult are haploid due to elimination of the paternal chromosomes at an early developmental stage.
This variant is called the diaspidid system after the scale insect clade (Diaspididae) where it was discovered.
[7] Genetically this system is equivalent both to haplodiploid arrhenotoky where the males are haploid and develop from unfertilized eggs and to certain cases of diploid arrhenotoky where the males get a diploid chromosome set from their mother but inactivate and fail to pass on half of them.