Description

Appearance & Distinctive Coloration

• Males are notable for their deep blue or dark blue carapace, with chelipeds and legs often reddish, light brown, green, or even sky blue depending on locality.

• Adult carapace breadth may reach up to ~50 mm, with unequal claws—a larger cheliped typically on one side, used in territorial displays.

Habitat & Behavior

• Endemic to Hong Kong and nearby Shenzhen, this species is semi‑terrestrial: males and females live in burrows along stream banks typically below 100 m elevation.

• Nocturnal and aggressive: active at night, they excavate burrows in moist soil, often emerging after rain to forage.

Ecology & Life History

• Carnivorous and highly territorial: known to prey on or attack other similar-sized freshwater crabs, crayfish, scorpions, or fish.

• Males may stay with females in the same burrow for extended periods post-mating, while females brood eggs until spring before young emerge.

• Lifespan may reach 2–5 years in captivity, and possibly up to 10 years in the wild.