Gryllus is a genus of field cricket (Orthoptera, Gryllidae, Gryllinae). Members of the genus are typically 15–31 mm long and darkly coloured. The type species is Gryllus campestris L.: the European field cricket. Until the mid-1950s, native field crickets in eastern North America were all assigned to a single species, Acheta assimilis Fabricius. Although regional variation in calling song and life history were noted, no morphological characters could be found to reliably distinguish these variants. Building upon the pioneering work of Fulton, Alexander used male calling song, life history and crosses between putative species to revise the taxonomy of gryllines in the eastern United States, and recognized five species, although at the time they were still classified in the genus Acheta. Species The genus contains the following species : Gryllus abditus Otte & Peck, 1997 Gryllus abingdoni Otte & Peck, 1997 Gryllus abnormis Chopard, 1970 Gryllus alogus Rehn, 1902 – damp-loving field cricket Gryllus amarensis (Chopard, 1921) Gryllus ambulator Saussure, 1877 Gryllus argenteus (Chopard, 1954) Gryllus argentinus Saussure, 1874 Gryllus armatus Scudder, 1902 Gryllus assimilis (Fabricius, 1775) – Jamaican field cricket Gryllus ater Walker, 1869 Gryllus barretti Rehn, 1901 Gryllus bellicosus Otte & Cade 1984 Gryllus bicolor Saussure, 1874 Gryllus bimaculatus De Geer, 1773 Gryllus braueri (Karny, 1910) Gryllus brevecaudatus (Chopard, 1961) – short-tailed field cricket Gryllus brevicaudus Weissman, Rentz, Alexander & Loher 1980 Gryllus bryanti Morse, 1905 Gryllus campestris Linnaeus, 1758 Gryllus capitatus Saussure, 1874 Gryllus carvalhoi (Chopard, 1961) Gryllus cayensis Walker, 2001 – Keys wood cricket Gryllus chaldeus (Uvarov 1922) Gryllus chappuisi (Chopard, 1938) Gryllus chichimecus Saussure, 1897 Gryllus cohni Weissman, Rentz, Alexander & Loher 1980 Gryllus comptus Walker, 1869 Gryllus conradti (Bolivar, 1910) Gryllus darwini Otte & Peck 1997 Gryllus debilis Walker, 1871 Gryllus firmus Scudder, 1902 – sand field cricket Gryllus fultoni (Alexander, 1957) – southern wood cricket Gryllus fulvipennis Blanchard, 1854 Gryllus galapageius Scudder, 1893 Gryllus genovesa Otte & Peck 1997 Gryllus insularis Scudder, 1876 Gryllus integer Scudder, 1901 – western trilling cricket Gryllus isabella Otte & Peck 1997 Gryllus jallae Giglio-Tos, 1907 Gryllus kapushi Otte, 1987 Gryllus krugeri Otte, Toms & Cade 1988 Gryllus lineaticeps Stål, 1861 – variable field cricket Gryllus luctuosus (Bolivar, 1910) Gryllus madagascarensis Walker, 1869 Gryllus marchena Otte & Peck 1997 Gryllus maunus Otte, Toms & Cade 1988 Gryllus maximus (Uvarov 1952) Gryllus meruensis Sjöstedt, 1909 Gryllus miopteryx Saussure, 1877 Gryllus multipulsator Weissman 2009 – Long-chirp Field Cricket Gryllus mzimba