Close up wild crustaceans found in its natural habitat, fiddler crabs foraging and sipping minerals in a puddle of water in the muddy tidal flat at Gaomei wetlands preservation area, Taichung, Taiwan

crab crustacean ocypodidae arcuatus wildlife claw forage eat sexually dimorphic fauna species ecosystem animal male mangrove wetland calling female shell gelasimus environment mud marsh fiddler coastal water puddle nature marine tubuca bowed beach sediment muddy gaomei sand tidal arcuata swamp taiwan preservation habitat soil taichung ground natural asymmetric flat borealis