The corrupt ones are decapodous crustaceans and belong the Callianassidae family and to the Callichirus genus. Some measure few millimeters while some species that inhabit lagoons formed for chorales arrive to measure up to 30 cm. The Callichirus genus, possesss about 90 species in the world, being that alone in Australia they had been registered about 60 species. In the Atlantic Occidental person they are represented by 6 species to know:

Callichirus branneri - With distribution of the Bermuda, Flórida, Antilhas and Nort of the South America, Brazil (of the Ceará until the Bahia).

Callichirus guara - With distribution in Brazil of Pará until São Paulo.

Callichirus guassutinga - With distribution of the Flórida, Antilhas and Brazil (of Pernambuco until Santa Catarina .

Callichirus jamaicensis - With distribution of the Flórida, Gulf of Mexico, Antilhas and Brazil (of Pará until the Bahia).

Callichirus major - With distribution of the East of the United States, Gulf of Mexico and Brazil (since the Bahia until the Rio Grande Do Sul).

Callichirus mirim - With distribution in Brazil of the Bahia until the Rio Grande do Sul

The species found in our state are Callichirus major and Callichirus mirim or minor Callichirus. The first presents bigger individuals approximately reaching 20 cm having abdomem it with yellowish coloration. The minor Callichirus, with lesser dimensions, about 15 cm in adult individuals, has a color reddish in abdomem it. As some crabs, them also they possess claws in form of clamps being the one of them well biggest one who to another one.

They live vertically in deep burrows with some ramifications excavated in the sand. Rare they are seen outside of its hiding place and its capture alone is possible with the aid of a suction bomb. They are fed of organic substance in decomposition and small animals that fall in its net of tunnels. Used as bait very they are appreciated mainly by biterras, corvinas, borriquetes, violas and miraguaias. They must be moored to the hook therefore its structure is extremely delicate.