Acridoidea Explained

Acridoidea is the largest superfamily of grasshoppers in the order Orthoptera with over 11,000 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.