Thick-legged Fiddler Crab (Paraleptuca crassipes). They have this one large claw that they wave around to impress mates. (671k)
Here are the pictures of Thick-legged Fiddler Crab (Paraleptuca crassipes) with links to the pages on which they appear, links to the full sized picture, and the description of the picture with links to the entry in iNaturalist (inaturalist.org)
All pictures are © Dr. Günther Eichhorn, unless otherwise noted.
Borneo Fauna
Dr. Günther Eichhorn Travel Website
Soaring website