This page will enable you to recognize and differentiate between different species of piranha
This is the picture of the "white piranha"(serrasalmus rhombus) It is sometimes classified as a pirambeba, although it does have some qualities of the dangerous species. It is not considered highly dangerous to man, although I wouldn't stick MY hand into and aquarium with one of these hungry devils! Notice the "weak" jaw structure and concave forehead. These are generally signs of less dangerous species.
Here is one of the typical pirambebas. It's name is serrasalmus brandti:
It is a piranha, it does have sharp teeth, but----if you notice the weak jaw structure, you can see that it is hardly any danger to man.
This piranha species (s. brandti) illustrates the differences between the dangerous species and the "weak" species of piranha- when compared to s. niger below.
This "black piranha" (serrasalmus niger) is one of the highly dangerous piranhas; it has the familiar convex forehead and strong jaw structure.
Unlike the popular myths, not all piranhas are to be considered "dangerous" to man. All piranhas are characid fish classified under one name: "Serrasalmus"
Under the genus "Serrasalmus" there consists two types of piranhas: The extremely dangerous, snub-nosed type----and the "wimpy" elongated nose type. The dangerous type of piranha, or piranha verdadeiras(vare-dah-day-ras), consists mainly of a highly compressed fish with a convex forehead. The less dangerous type, pirambebas(peer-om-bay-bas), consists of a fish with a less powerful jaw structure and concave forehead.
Another piranha seen often the the pet store is the wimple piranha.(Catoprion mento) Although not classified as a true piranha, it has the characteristics of one--including the sharp teeth.
The wimple is a small fish-rarely exceeding 4 inches. It is quite a nervous fish and will tend to hide a lot. It requires dense vegetation. The wimple is primarily a scale and fin eater, and will attack anything smaller than itself. Therefore it shouldn’t be kept with other fish, including other piranha. It should be feed bloodworms, tubifex worms, bits of lean beef and fish. The wimple piranha can be fed feeder fish, but it’s merely torture due to the wimple’s fin and scale method of dispatching it’s prey.