Gryllinae

Gryllinae, or field crickets, are a subfamily of insects in the order Orthoptera and the family Gryllidae.
They hatch in spring, and the young crickets (called nymphs) eat and grow rapidly. They shed their skin (molt) eight or more times before they become adults.
Field crickets eat a broad range of food: seeds, plants, or insects (dead or alive). They are known to feed on grasshopper eggs, pupae of Lepidoptera (moths and butterflies) and Diptera (flies). Occasionally they may rob spiders of their prey. Field crickets also eat grass.
In the British Isles "field cricket" refers specifically to Gryllus campestris, but the common name may also be used for G. assimilis, G. bimaculatus, G. firmus, G. pennsylvanicus, G. rubens, and G. texensis, along with other members of various genera including Acheta, Gryllodes, Gryllus, and Teleogryllus.
Acheta domesticus, the House cricket, and Gryllus bimaculatus are raised in captivity for use as pets.
Identification
Field crickets are normally in size, depending on the species, and can be black, red or brown in color. While both males and females have very similar basic body plans, each has its own distinguishing feature(s).
Females can be identified by the presence of an ovipositor, a spike-like appendage, about long, on the hind end of the abdomen between two cerci. This ovipositor allows the female to bury her fertilized eggs into the ground for protection and development. In some female field crickets, species can be distinguished by comparing the length of the ovipositor to the length of the body (e.g., G. rubens has a longer ovipositor than G. texensis).
Males are distinguished from females by the absence of an ovipositor. At the end of the abdomen there are simply two cerci. Unlike females, however, males are able to produce sounds or chirps. Thus, males can be identified through sound while females cannot.
Diagram A shows the male cricket with its wings raised for the purpose of chirping. Diagram B shows the female cricket, identified via the long protruding ovipositor at the end of the abdomen. D and E show the female using the ovipositor to deposit the fertilized eggs into the ground. Diagram C shows a topical and side view of nymphs with no protrusion at the hind of the abdomen.
Behaviour
In ambient temperatures between and sexually mature males will chirp, with the acoustical properties of their calling song providing an indicator of past and present health. Females evaluate these songs and move towards the ones that signal the male's good health. When the male senses the presence of a female he will produce a softer courting song. After mating, the female will search for a place to lay her eggs, preferably in warm, damp (though not wet) soil.
Field crickets prefer to live in outdoor environments with high humidity, warm temperatures, moist rich soil, and adequate food, but will migrate into human structures when environmental conditions outside become unfavorably cool. They often gain entry into buildings via open doors and windows as well as cracks in poorly fitted windows, foundations, or siding.
Unlike House crickets, which can adapt themselves to indoor conditions, populations of field crickets living in human structures and buildings and without access to warm moist soil for depositing their eggs tend to die out within a few months. Consequently, field crickets in temperate regions exhibit diapause.
Tribes and selected genera
Six tribes have been identified in this subfamily:
Cephalogryllini
Auth.: Otte & Alexander, 1983 - Australia
Apterogryllus Saussure, 1877
Cephalogryllus Chopard, 1925
Daintria Otte, 1994
Notosciobia Chopard, 1915
Eurygryllodini
Auth.: Gorochov, 1990 - Australia
Eurygryllodes Chopard, 1951
Maluagryllus Otte, 1994
Gryllini
Worldwide, selected genera include:
Acheta Fabricius, 1775
Brachytrupes Serville, 1838
Gryllodinus Bolívar, 1927
Gryllita Hebard, 1935
Gryllodes Saussure, 1874
Gryllus Linnaeus, 1758
Gymnogryllus Saussure, 1877
Loxoblemmus Saussure, 1877
Melanogryllus Chopard, 1961
Miogryllus Saussure, 1877
Teleogryllus Chopard, 1961
Modicogryllini
Worldwide except the Americas, selected genera include:
Eumodicogryllus Gorochov, 1986
Lepidogryllus Otte & Alexander, 1983
Modicogryllus Chopard, 1961
Velarifictorus Randell (1964)
Sciobiini
Auth.: Randell, 1964 - NW Africa, Iberian peninsula
Sciobia Burmeister, 1838
Turanogryllini
Auth.: Otte, 1987 - Africa, SE Europe, Middle East, southern Asia through to Korea and Indo-China
Neogryllopsis Otte, 1983
Podogryllus Karsch, 1893
Turanogryllus Tarbinsky, 1940
Genera incertae sedis
Allogryllus Chopard, 1925
Apiotarsus Saussure, 1877
Callogryllus Sjöstedt, 1910
Coiblemmus Chopard, 1936
Comidoblemmus Storozhenko & Paik, 2009
Cryncus Gorochov, 1983
Danielottea Koçak & Kemal, 2009
Gryllodeicus Chopard, 1939
Grylloderes Bolívar, 1894
Hispanogryllus Otte & Perez-Gelabert, 2009
Itaropsis Chopard, 1925
Jarawasia Koçak & Kemal, 2008
Mayumbella Otte, 1987
Meristoblemmus Jones & Chopard, 1936
Nemobiodes Chopard, 1917
Oediblemmus Saussure, 1898
Oligachaeta Chopard, 1961
Omogryllus Otte, 1987
Platygryllus Chopard, 1961
Parasciobia Chopard, 1935
Qingryllus Chen & Zheng, 1995
Rubrogryllus Vickery, 1997
Songella Otte, 1987
Stephoblemmus Saussure, 1877
Stilbogryllus Gorochov, 1983
Svercoides Gorochov, 1990
Taciturna Otte, 1987
Thiernogryllus Roy, 1969
Zebragryllus Desutter-Grandcolas & Cadena-Castañeda, 2014
References
Orthoptera subfamilies