Acridoidea Explained

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.^{[1] [2]} 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♀.^[2] 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.^[2] There is some support for 'Mesa's hypothesis' of an ancestral pericentric inversion in the ancestor of Ommexechinae to explain this karyotype variation.^{[3] [4] [2] [5]}

Notes and References

1. Book: G. M. Hewitt . B. John. H. Bauer. H. Kayano. A. Levan. M. White. 1979. Animal cytogenetics 3. Berlin: Gebrüder Borntraeger. Insecta 1: Orthoptera. Grasshoppers and crickets.
2. A. Mesa. A. Ferreira. C. S. Carbonell. 1982. Cariología de los acridoideos neotropicales: estado actual de su conocimiento y nuevas contribuciones. Annales de la Société Entomologique de France. 18. 507–526.
3. A. Mesa. 1963. Acerca de la cariología de Ommexechidae (Orthoptera-Acridoidea). Revista de la Sociedad Uruguaya de Entomología. 5. 37–43.
4. A. Mesa. A. Ferreira. 1977. Cytological studies in family Ommexechidae (Orthoptera-Acridoidea). Acrida. 6. 261–271.
5. Santander, Mylena D.. Cabral-de-Mello, Diogo C.. Taffarel, Alberto. Martí, Emiliano. Martí, Dardo A.. Palacios-Gimenez, Octavio M.. Castillo, Elio Rodrigo D.. New insights into the six decades of Mesa's hypothesis of chromosomal evolution in Ommexechinae grasshoppers (Orthoptera: Acridoidea). Zoological Journal of the Linnean Society. 2021. 193. 4. 1141–1155. 10.1093/zoolinnean/zlaa188.