Euastacus sp. (genus) (Spiny crayfish)

Class Malacostraca, order Decapoda, family Parastacidae.

Excerpt from Wikipedia: Euastacus is a genus of freshwater crayfish known as "spiny crayfish". They are found in the south-east of the Australian mainland, along with another genus of crayfish, Cherax. Euastacus crayfish are distinguished from the smooth-shelled Cherax species by the short robust spikes on their claws and carapace, and frequently, their larger size. The genus Euastacus is restricted to the south-east of the Australian mainland. There is a high degree of endemism in Euastacus species in coastal river systems, with many species restricted to single river or creek catchment. Euastacus species occur in several upland reservoirs. Euastacus species are extremely slow growing, long-lived (possibly 40+ years in some species), and late to reach sexual maturity. These biological characteristics make Euastacus species vulnerable to environmental disturbances and essentially unable to support to catch-and-kill fisheries.  https://en.wikipedia.org/wiki/Euastacus