Extension range of four species of freshwater crabs (Decapoda: Trichodactylidae) in the state of Maranhão, Northeastern Brazil

The present study provides a list of the freshwater crab species of the family Trichodactylidae recorded from the state of Maranhao, northeastern Brazil, along with information about their distribution. Eight streams were sampled with dip nets, sieves, gill nets, and drag nets. Four species were found: Dilocarcinus septemdentatus (Herbst, 1783), Goyazana castelnaui H. Milne Edwards, 1853, Sylviocarcinus pictus (H. Milne Edwards, 1853), and Valdivia serrata White, 1847. Our results increase the known distribution range of these species and add new records to more basins.