The ball python (Python regius), also called the royal python, is a python species native to West and Central Africa, where it lives in grasslands, shrublands and open forests. It is listed as Least Concern on the IUCN Red List because of its wide distribution. It is threatened by hunting for its meat and for the international pet trade. This nonvenomous constrictor is the smallest of the African pythons, growing to a maximum length of 182 cm (72 in). The name “ball python” refers to its tendency to curl into a ball when stressed or frightened.
The ball python is black or dark brown with light brown blotches on the back and sides. Its white or cream belly is scattered with black markings. It is a stocky snake with a relatively small head and smooth scales. It reaches a maximum adult length of 182 cm (6.0 ft). Males typically measure eight to ten subcaudal scales, and females typically measure two to four subcaudal scales.Females reach an average snout-to-vent length of 116.2 cm (45.7 in), a 44.3 mm (1.74 in) long jaw, an 8.7 cm (3.4 in) long tail and a maximum weight of 1.635 kg (3.60 lb). Males are smaller with an average snout-to-vent length of 111.3 cm (43.8 in), a 43.6 mm (1.72 in) long jaw, an 8.6 cm (3.4 in) long tail and a maximum weight of 1.561 kg (3.44 lb). Both sexes have pelvic spurson both sides of the vent. During copulation, males use these spurs for gripping females. Males tend to have larger spurs, and sex is best determined by manual eversion of the male hemipenes or inserting a probe into the cloaca to check the presence of an inverted hemipenis.