Acridoidea
Introduction ''Teratodes monticollis'''''Acridoidea''' is the largest superfamily of grasshoppers in the order Orthoptera with species found on every continent except Antarctica.
Classification ''Orthoptera Species File'' includes the following families:*Acrididae MacLeay, 1821*Dericorythidae Jacobson & Bianchi, 1905*Lathiceridae Dirsh, 1954*Lentulidae Dirsh, 1956*Lithidiidae Dirsh, 1961*Ommexechidae Bolívar, 1884*Pamphagidae Burmeister, 1840*Pamphagodidae Bolívar, 1884*Pyrgacrididae Kevan, 1974*Romaleidae Pictet & Saussure, 1887*Tristiridae Rehn, 1906
Chromosomes 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. In species of Acrididae and Romaleidae it is common to have acrocentric chromosomes with a fundamental number (FN), i.e. number of chromosome arms, of 23♂/24♀. 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. There is some support for 'Mesa's hypothesis' of an ancestral pericentric inversion in the ancestor of Ommexechinae to explain this karyotype variation.
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