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Ecological Exploration

Mudflat crab

Crustacea | Varunidae
Chasmagnathus convexus


The mudflat crab mostly comes out at dusk. Its body size is large, with a 3-4 cm carapace width. These crabs have diverse body colors which can be generalized into two types: purple and yellow. Their eyestalks and carapace are red, as well as the joints of their pereopods. The mudflat crab mostly inhabits grass marshes in estuaries and is omnivorous. These crabs feed on carcasses of other crabs and animals, as well as plant fragments. It is difficult to observe the convex mudflat crab closely as they are sensitive to disturbance. Telescopes can be used to observe how they forage. In addition, purple type crabs are very colorful and sparkle like shiny gems when the sun sets.


The convex mudflat crab can be seen on the mudflats by the shore at Gaomei Wetlands.


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