Description

 Goneplax rhomboides has a distinctive rectangular carapace (up to 4 cm across) with a conspicuous spine at each anterior corner, and a short, straight-edged lobe between long, thick eyestalks. The chelipeds are long and slender and those of the male crab can reach up to 5 times the length of the carapace. The dorsal surface of the carapace varies from yellow to red and may be fringed with violet. The chelipeds and walking legs range from yellow to orange in colour.