Females also appear to be a darker colour, but only because of the presence of mud particles on the carapace; both sexes are naturally unpigmented.

[2] Cancrocaeca is known only from fresh water in three karstic caves in Maros Regency, Sulawesi (Indonesia).

[2][1] Cancrocaeca was discovered in a cave in southern Sulawesi in 1989, as part of an expedition by the Association Pyrénéenne de Spéléologie ("Pyrenean Speleological Association"); the expedition collected a number of crabs and sent them to Peter K. L. Ng of the National University of Singapore for identification.

Among a large number of Parathelphusa specimens, he discovered a single male of Cancrocaeca.

[2] In ancient Greek, morphos is not attested, while morphē (μορφή) means "shape" or "form".