About Euastacus spinifer (Heller, 1865)
Euastacus spinifer (Heller, 1865) is a species of freshwater crayfish in the family Parastacidae, endemic to Australia. It was first described in 1865 by Camill Heller under the name Astacoides spinifer, and has been redescribed many times since. The argument for synonymizing the multiple published names for this species has been accepted. This species is endemic to Australia, where it occurs from near sea level up to 1,200 metres (3,900 ft) in elevation, across a total distribution area of 55,000 square kilometres (21,000 sq mi). Its usual habitats are creeks and estuaries, and these habitats are typically shaded by vegetation. Mating occurs in winter, when temperatures drop as low as 15 °C (59 °F), and females lay eggs in early July. Eggs are carried on the female's pleopods, and hatch after an incubation period of 110 to 140 days. Hatchlings remain with their parents until early summer. Males reach sexual maturity in 5 to 6 years, growing to around 11 centimetres (4 in) long at maturity. Females require about 8 years to reach maturity, and grow to lengths over 14 centimetres (6 in). A variant group called "precious males" reaches maturity at just 4 centimetres (2 in) in length. Slight variations to this reproductive cycle occur across populations from different river systems.
