Here is a stamp which combines two of my fascinations—catfish and Namibia. Of course Namibia is a vast and profoundly arid desert—literally a sea of sand—so perhaps you are wondering how a catfish made it onto their postage. Well the African sharptooth catfish (Clarias gariepinus) has a habit of getting everywhere. It lives throughout most of Africa and the Middle East and (though ill-conceived aquaculture) has established colonies in Vietnam, India, Brazil, and Indonesia. The catfish is an air breather. It can sip pure air without the use of its gills, so it can survive in puddles, mud wallows, and even in filthy anaerobic water. Some of them have moved into the sewers of big cities. Speaking of big it is arguably Africa’s largest catfish with an average adult length of 1–1.5 m (3 ft 3 inches –4 ft 11 inches). Even in a dry land like Namibia this tough persistent catfish manages to find watercourses of one sort or another. Like its close cousin, the walking catfish of Asia, the African sharptooth catfish is a remarkable creature.