Acheta domesticus

Acheta domesticus

The house cricket (Acheta domesticus Linnaeus, 1758) is an insect belonging to the Gryllidae family.

Systematic –
From a systematic point of view it belongs to:
Eukaryota domain,
Kingdom Animalia,
Subkingdom Eumetazoa,
Superphylum Protostomia,
Phylum Arthropoda,
Subphylum Tracheata,
Superclass Hexapoda,
Class Insecta,
Subclass Pterygota,
Exopterygota cohort,
Subcohort Neoptera,
Superorder Polyneoptera,
Section Orthopteroidea,
Order Orthoptera,
Suborder Ensifera,
Gryllidae family,
Subfamily Gryllinae,
Gryllini Tribe,
Genus Gryllus,
Subgenus Gryllus,
Species A. domesticus.
The term is basionym:
– Gryllus domesticus Linnaeus, 1758.
The terms are synonymous:
– Acheta melanocephalus Zacher, 1917;
– Gryllulus domesticus (Linnaeus, 1758);
– Gryllus aegyptiacus Haan, 1843;
– Gryllus transversalis Walker, 1871.

Geographic Distribution and Habitat –
The Acheta domesticus is an insect presumably native to south-western Asia and imported to America in the 18th century.
It is a species with a Holarctic distribution, being present in Eurasia, North America and North Africa.
Its preferential habitats are different, being found in woods, caves, fields, under trunks and rocks or on the sides of roads; it can also be found inside piles of wood, bricks and stones.
However, it is found mainly in humid or weedy areas. Furthermore, being very attracted to heat, it is often induced to live in the immediate vicinity of humans, in the areas surrounding homes, landfills and commercial buildings, where it can receive sufficient nourishment and humidity.
This insect is also bred and sold mainly in the United States, Canada, China, Japan and Thailand.

Morphology –
The Acheta domesticus is an insect, which manifests sexual dimorphism, which is recognized by having a yellowish-brown body and head with black spots and bands, with a size of around 16-21 millimetres.
The hind wings are long and protrude from the more rigid front ones (tegmina).
Males and females look similar, but females have an ovipositor measuring approximately 10–15 mm.
The ovipositor is brown-black in color, and is surrounded by two appendages.
Both males and females have appendages but on males they tend to be more prominent.
The front wings of male crickets are shorter than those of females and the scrapers are enlarged to better reproduce the singing sound that is generated through the friction of the first pair of wings; males generate a high-pitched sound.

Aptitude and biological cycle –
The life cycle of the Acheta domesticus is completed in two or three months, if raised at 25-30 °C, and is completed through 6 stages (with five moults) in which the cricket will go from approximately 1 mm in length to 2 cm .
Starting from the third molt (fourth stage) the sexes begin to be easily distinguished thanks to the outline of the ovipositor exhibited by the females, who need sand or soil to lay their eggs.

Ecological Role –
The Acheta domesticus is a nocturnal insect, although, according to the University of Missouri Extension, during the hours of darkness, many crickets are attracted to lit buildings.
These insects show a predilection for high temperatures, for dark areas in which to take refuge and are attracted to the light of buildings. This is how they are usually found in kitchens, basements, sheds and anywhere in the house.
In general, it is only the male who sings and performs two types of song: a powerful one and a weak one, with which he approaches the female just before the deposition of the spermatophore. It produces its chirping by rubbing a series of ridges on one wing, as if they were a plectrum, against a scraper on the opposite wing. Hypothetically this means that a cricket could produce two distinct songs using both sides. Sound frequency is a reliable indicator of male size: a female cricket can tell how big a male is simply by listening to the pitch of the song.
This insect, in the presence of large populations, can cause direct damage with its mouth or can be indirectly harmful as a vector of pathogens. In these cases, control is carried out using poisoned bait.
In turn it is kept at bay by various predators. These include cats, herons and geckos. Basically, when the cricket notices the presence of possible predators, it stops its song.
It is a sociable and less territorial species than the field cricket; it can devour weaker members of its species when food is scarce. They are omnivorous, they feed on everything they find around them.
Its diet consists mainly of a variety of vegetables, fruit, cereals and small nocturnal insects, but fabrics can also be attacked. In case of breeding, food is used that contains extra calcium which is necessary for amphibians. It is also cannibalistic and often feeds on conspecifics.
House cricket is a good source of protein for other arthropods, birds, amphibians, reptiles and fish and, therefore, is easily available in large numbers at pet stores.
For this reason it is considered the basic food for any insectivorous reptile, as it is not fatty, contains a lot of protein and is easy to raise at home in small numbers. The breeding temperature is the best system for controlling the speed of reproduction. You may get different results if you use limit values:
– 18-20 °C: crickets barely grow and eggs take almost 4 weeks to hatch. The entire life cycle can take 5 months;
– 32-34 °C: the eggs hatch in just one week and the life cycle is completed in approximately 7-8 weeks;
Lack of water is the number one cause of cannibalism and the supply of water is essential. You can use a bird drinker, with the spout filled with cotton wool or a shallow plastic lid filled with a wet sponge, as smaller crickets drown easily.
Please remember that, traditionally, this insect has been bred in China and Japan, and kept indoors, to delight the inhabitants for almost a thousand years. Appreciated for his singing, he was kept in small cages made of bamboo or other material. During the Sung dynasty (960-1279 AD) the habit of making him fight came into vogue. Numerous books have been written detailing the collection, care and feeding of crickets, as well as techniques for conducting a proper fight. Special diets of rice mixed with cucumbers or lotus seeds were also adopted for the crickets.

Guido Bissanti

Sources
– Wikipedia, the free encyclopedia.
– GBIF, the Global Biodiversity Information Facility.
– Russo G., 1976. Agricultural Entomology. Special Part. Liguori Editore, Naples.
– Pollini A., 2002. Manual of applied entomology. Edagricole, Bologna.
– Tremblay E., 1997. Applied entomology. Liguori Editore, Naples.

Photo source:

– https://inaturalist-open-data.s3.amazonaws.com/photos/305285562/original.jpg