Acridoidea is the largest superfamily of grasshoppers in the order Orthoptera with over 11,000 species found on every continent except Antarctica.

[2] Orthoptera Species File includes the following families:[2] Among the families Acrididae, Ommexechidae and Romaleidae there is reported to be chromosomal stability with a high frequency of species harbouring diploid number (2n) of 23♂/24♀ chromosomes.

[4] However, chromosomal rearrangements are frequently found as deviations from the standard acrocentric karyotype.

In the subfamily Ommexechinae most species show a unique karyotype (2n = 23♂/24♀, FN = 25♂/26♀) due to the occurrence of a large autosomal pair (L1) with submetacentric morphology.

[4] There is some support for 'Mesa's hypothesis' of an ancestral pericentric inversion in the ancestor of Ommexechinae to explain this karyotype variation.