[3] The anterior of the carapace is linear-edged, with two eye orbits, which are curved and situated in the two frontal corners.

[4] The smooth shore crab's natural range is New Zealand and Chile in the Juan Fernandez Islands.

[1][8] C. lavauxi has been found to reside in a number of New Zealand sites from the Hohoura Harbour to Westland[1] with significant populations in the North Island.

[5] C. lavauxi can be found in a variety of environments,[9] including boulders, under stones, and on beaches ranging from exposed shores to protected bays.

The crabs are not monogamous, and both females and males will mate multiple times during the breeding season.

[13] Females carry eggs between November and February[14] and have a short reception time of fewer than 24 hours, or almost a week in captivity.

[12] The eggs initially are a dark purple colour, but grow paler and develop black eyespots as they mature.

[12] C. lavauxi tend to moult soon after the breeding season has ended, in late summer to early autumn.

[13] C. lavauxi is a scavenger crab, foraging on deceased animals and plants,[3] although in most cases it is a herbivore.

Studies also suggest that females do not avoid either the unparasitized and parasitized males due to there being no visible disadvantages to either.

C. lavauxi displays a number of other unique behavioural traits including its aggressiveness when cornered, raising its pincers to accentuate its size along with showing their paleness.

[1] The common body posture of C. lavauxi is being flat with pincers folded and lying on the ground with its walking legs close and side-by-side.

When in a raised position, it places its body at a 45 degree angle with its back part still lying on the ground with pincers resting still either flat or poised at the midway mark.

[1] Further, C. lavauxi can make clicking noises with the sound acting as a sort of distant artillery.