Wild crustacean found in its natural habitat, a male fiddler crab and female sand fiddler crab sipping minerals on the tidal flat at Gaomei wetlands preservation area, Taichung, Taiwan

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