Stimpson, 1858
Carapace sometimes very broadened, pentagonal or rounded in outline, with more or less developed and lamelliform lateral expansions, concealing the ambulatory legs or part of them. Dorsal surface flattened or even concave. Posterior border sometimes very broad. Front produced, obtusely triangular or toothed. Chelipeds stout and depressed, exposed. Ambulatory legs slender and smooth. (Guinot 1998)
Species included:
Cryptocnemus kamekii Sakai, 1961
Cryptocnemus macrognathus Ihle, 1915 (new for Japan: Komatsu & Takeda, 2000)
Cryptocnemus obolus Ortmann, 1892
Cryptocnemus pentagonus Stimpson, 1858
Cryptocnemus trigonus Komatsu & Takeda, 2000