West African fossorials, large, and notable for something almost no other tarantula does: they will voluntarily enter water and stay submerged, using trapped air on the abdomen.
H. gigas is the common one. Deep burrower, needs real substrate depth, defensive when reached, and it grows to a size that makes the burrow a genuine excavation project. Old world, so no urticating hairs and a threat display instead.
Cameroonian and Nigerian material still moves, unlike much of the African trade, so supply is a mix of captive-bred and imported. That keeps prices low and also keeps quality inconsistent, since a wild-caught adult of unknown age is a different purchase than a captive-bred juvenile at the same price.