Metaplax elegans
Carapace quadrilateral. Distance between the outer margins of the eye orbits greater than the length of the carapace. Eyestalks as long as the frontal margin. In males, infra orbit ridge below orbit of eye with more than 40 lobules, females with about 30-40. Propodus of male cheliped longer than high. Chelipeds are nearly equal in size and orange in colour. Merus of pereiopods 2-5 with 8-9 spines on upper margin.
Vernacular name: Orange signaller crab.
These crabs are often found on soft muddy substrates because they feed mainly on worms. Males display to females by waving their long and bright orange chelipeds, and moving their bodies up and down, as if they are “signalling” to each other.
Order Decapoda Latreille, 1802
Infraorder Brachyura Latreille, 1802
Section Eubrachyura de Saint Laurent, 1980
Subsection Heterotremata Guinot, 1977
Superfamily Grapsidoidea Macleay, 1838
Family Varunidae Milne Edwards, 1853
Metaplax elegans De Man, 1888
Burma (Mergui Archipelago), Thailand, Indonesia and Singapore and China (Guangdong).
Mangroves on soft mud.