[3] It was not until the 1920s that Hilbrand Boschma pointed out these two purported species, at the time placed in separate families, were but two distinct growth stages of the same organism and united them under Clistosaccus.

[6] After an infective female cyprid larva has settled on a suitable host, it pierces the cuticle with its antennule and injects some cells into the abdomen of the hermit crab.

Here they develop directly into cyprid larvae, missing out the nauplius stage of more typical crustaceans.

The cyprid larvae are at first unisex, becoming male or female according to what role they play in the reproductive cycle.

The presence of this parasite effectively sterilises the host hermit crab, the gonads do not degenerate, but they fail to produce mature eggs and sperm.