A new species of Corydoras, with a colour pattern resembling that of C. arcuatus, C. narcissus and C. gracilis, has been described by scientists.
Named Corydoras urucu, it was discovered in the Rio Urucu basin, one of the right-bank tributaries of the Amazon known as the Rio Solimoes.
Unlike the other three species bearing a dark stripe along the top of each flank, that in Corydoras urucu stops before the nose.
It also differs from arcuatus and narcissus in that the posterior end of the stripe reaches the lower rays of the caudal fin. It also has a more rounded snout profile.
Although its colour pattern is similar to other Corydoras, the authors reckon the pattern was independently acquired.