Wikipedia
Perisesarma
Perisesarma is a genus of mangrove crabs in the family Sesarmidae (or Grapsidae in some classifications) predominantly found in the Indo-Pacific. There are 23 species as of late 2006 with two from west Africa: P. kammermani (De Man, 1883) & P. alberti Rathbun, 1921. They are typically small semi-terrestrial crabs found on the forest floor at low tide. They eat nearly anything they can and will try to eat anything that doesn't threaten them — including pencils and other objects dropped on the forest floor. The last species of the genus described is Perisesarma samawati by Gillikin and Schubart (2004). P. samawati can be found in East Africa along with P. guttatum, but its sister species is P. eumolpe from Malaysian mangroves