The Holy Grail of loaches, Leptobotia elongata, the imperial flower loach, elongate loach or royal clown loach, is a species of botiid fish found in flowing water in the upper and middle Yangtze basin in China. It is the largest species in the family, reaching up to 50 cm in length and 3 kg in weight. Predominantly a riverine loach favoring clear, well-oxygenated, running water with substrates of rocks and gravel. Often present in bedrock and boulder-filled headwater streams but also found in larger, turbidriver channels.