Tenuibranchiurus is a genus of diminutive freshwater crayfish that live in the Australian state of Queensland.

Tenuibranchiurus glypticus is reportedly the smallest species of crayfish in the world.

[2] It is distinguished from other crayfish by its small size, adults being only around 25 millimetres (1.0 in) long, and its claws which open vertically rather than horizontally or obliquely.

[2] Tenuibranchiurus lives in coastal wallum swamps, and stays among the sedges rather than in more open water.

[3] Additional populations have been found at the periphery of its range, but these are thought to represent new, undescribed species.