Serrasalmus Spilopleura Complex Form (Common Name: Black Diamond) from Brazil is part of fin nipping piranha family of S.Spilopleura piranhas of which the most common and known are the ones often documented in piranha books as those that bred at the Cincinatti Zoo. Predominently a fin biter, the species are quite solitary for this reason as they will almost certainly be biting off any neighbours fins and tails including including its own kind. They grow up to 12 inches in size and must be kept alone at all stages of size. The black diamond is an extremely tireless attacker of tails and fins and can leave a tank full of other piranhas with missing fins and tails. Should the black diamond be the same size or larger than its neighbouring piranhas, more than likely, the outcome for its neighbour would be death rather than simply missing fins and tails. The black diamond resembles somewhat in body form that of the black piranha, however it lacks the bulk and girth of the black piranha. It is extremely speckled silver with flame red eyes. Although it is less dangerous and difficult to handle than a black piranha, it maybe even more dangerous to other fish due to its relentless attack on fins and tails. At adult size, it feeds on whole pieces of fish as well as fin biting.

In conclusion, these fish are extremely aggressive and and should be kept one fish per tank. Body and eye colour is rather unique and the fishes' back is pointedly humped. No known pictures of this black diamond piranha exists in any piranha books as this is very new addition to fish trade and it quite rare, with perhaps only a handful out there.