Yeah, Hymenochirus sp are fully aquatic, as are all Pipid's, they will usually try to find a way to escape aquariums though, so not sure if they sometimes leave the water in the wild if the conditions are humid enough? ive also been told that Silurana (Tropical and Cameroon Clawed Frogs) species like to sometimes bask above the waterline apparantly, my ones sometimes sit on the plants slightly above the water line, they dont have access out of the water other than that though.