The Mesobatrachia are the second-largest of the Anura suborders of amphibians. It contains six families, 20 genera, and 168 species. Recognized as a group in 1993, the name (meso- "middle" batrachia "frogs") is contrasted with the primitive Archaeobatrachia and the more diverse and advanced Neobatrachia. The Mesobatrachia comprise five fossorial families, including the spadefoot toads of Europe, North America, and East Asia, the parsley frogs, and the Mexican burrowing toad, as well as one obligatorily aquatic family, the Pipidae of Africa and South America.