Misgurnus

The oriental weather loach, Misgurnus anguillicaudatus, is a loach native to Siberia, Korea, Japan, China and northern Vietnam. Known in the United States as the 'dojo loach', it is one of the most ubiquitously available species in the hobby, and years of mass-production have made health and morphological issues common. Exceptionally hardy and adaptable, it is established as an alien species around the globe, and its adult size of up to 280 mm should be considered prohibitive.

The large-scaled loach, Misgurnus dabryanus, is a 'true' loach from the Yangtze and Pearl rivers in China, plus Taiwan and the Amur in Russia. It is sold regularly in the hobby but almost always labelled as or mixed in with M. anguillicaudatus, from which it differs in its high adipose crests on the caudal peduncle and the lack of a dark spot at the caudal-fin base. It spends some of its time completely buried, so it needs a soft, sandy substrate.