Pygocentrus nattereri
http://images.google.co.uk/images?s...t=result&cd=1&q=Pygocentrus+nattereri&spell=1
Maximum Size: 12 inches
Body Characteristics: The majority of the fishs upper body is a silver, or black with silver speckles. Their belly is of course normally red in colour, however different belly colour varieties do exist, from yellow to orange and red. The tail is striped vertically with white blue and/or black. The head is convex (said to be blunt and bulldog like). Two nostrils are also clearly seen. In addition to the red pupil outline, a black line running vertically on each eye.
Distinctive Features: No humeral spot, Red eye outline with vertical line.
Pygocentrus cariba
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Pygocentrus+cariba
Maximum Size: 14 inches
Body Characteristics: Very similar to the red belly piranha, however the upper body is always silver or grey, apposed to the sometimes darker shaded red belly. They too have a red or orange underbelly, and silver speckles. Two nostrils can again be seen clearly. And the eye is silvery with a black vertical strip. Only main differences between the cariba and red belly is that they grow larger and have a distinctive humeral spot on each side.
Distinctive Features: Black humeral spot on each side, Clear eyes with vertical line.
Pygocentrus piraya
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Pygocentrus+piraya
Maximum Size: 24 inches
Body Characteristics: Very similar body characteristics at the cariba and red belly. With its blunt head, red or orange underbelly and large silvery eyes with black bands. However three things define it from the other two. Its much greater size, tufted adipose fin and underbelly colour that rises along the side of its body like flames.
Distinctive Features: Large size, Tufted adipose fin, Underbelly colours rising along side of fish.
Serrasalmus rhombeus
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+rhombeus
Maximum Size: 16 inches
Body Characteristics: The rhom goes through many physical changes, even when you think your rhom is old, it may in fact still be at its changing stages. Once they are fully mature, they will normally be a very dark or black colour, though there are exceptions to this. These exceptions and slight differences in profiles are due to their diverse distribution. But one thing all Rhoms have is striking red eyes.
Distinctive Features: Red eyes, High back, Large size.
Serrasalmus spilopleura
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+spilopleura
Maximum Size: 12 inches
Body Characteristics: Like with the Rhom, Spilo has many different variations due to their distribution. However usually they are gold or yellow in the lower body and more silverfish yellow the further back you go. However all Spilos caudal fin is lightly coloured with a dark base and has a dark terminal band. Although they have the red eyes like the Rhom, for a serra species their head is quite blunt.
Distinctive Features: Terminal band on caudal fin, Red eyes, Fairly blunt head.
Serrasalmus elongatus
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+elongatus
Maximum Size: 10 inches
Body Characteristics: This is not like any other piranha, its body is very stretched and elongated, hence the name. There are two different colour variants. One has a silvery body, with a dark tail fin and humeral spot. The other has a darker face and fins, orange to red pectoral fins, and traces of red in the lower face and gill plates.
Distinctive Features:Elongated body.
Serrasalmus brandtii
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+brandtii
Maximum Size: 12 inches
Body Characteristics: Normally gold but sometimes purely silver in colour, it have bright iridescent scales on its sides. The fins are normally transparent, the eyes are also colourless and the head is very concave.
Distinctive Features: Clear eyes, Very concave head.
Serrasalmus geryi
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+geryi
Maximum Size: 10 inches
Body Characteristics: They have a very bright shinning silver colour which nearly always sparkles. Unique to geryi is the violet or purple line running from the base of their dorsal fin to the tip of their jaw. The tail fin is dark with a white vertical band in the middle. The eyes are reddish though not completely red.
Distinctive Features: Violet or purple line, Slightly red eyes.
http://images.google.co.uk/images?s...t=result&cd=1&q=Pygocentrus+nattereri&spell=1
Maximum Size: 12 inches
Body Characteristics: The majority of the fishs upper body is a silver, or black with silver speckles. Their belly is of course normally red in colour, however different belly colour varieties do exist, from yellow to orange and red. The tail is striped vertically with white blue and/or black. The head is convex (said to be blunt and bulldog like). Two nostrils are also clearly seen. In addition to the red pupil outline, a black line running vertically on each eye.
Distinctive Features: No humeral spot, Red eye outline with vertical line.
Pygocentrus cariba
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Pygocentrus+cariba
Maximum Size: 14 inches
Body Characteristics: Very similar to the red belly piranha, however the upper body is always silver or grey, apposed to the sometimes darker shaded red belly. They too have a red or orange underbelly, and silver speckles. Two nostrils can again be seen clearly. And the eye is silvery with a black vertical strip. Only main differences between the cariba and red belly is that they grow larger and have a distinctive humeral spot on each side.
Distinctive Features: Black humeral spot on each side, Clear eyes with vertical line.
Pygocentrus piraya
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Pygocentrus+piraya
Maximum Size: 24 inches
Body Characteristics: Very similar body characteristics at the cariba and red belly. With its blunt head, red or orange underbelly and large silvery eyes with black bands. However three things define it from the other two. Its much greater size, tufted adipose fin and underbelly colour that rises along the side of its body like flames.
Distinctive Features: Large size, Tufted adipose fin, Underbelly colours rising along side of fish.
Serrasalmus rhombeus
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+rhombeus
Maximum Size: 16 inches
Body Characteristics: The rhom goes through many physical changes, even when you think your rhom is old, it may in fact still be at its changing stages. Once they are fully mature, they will normally be a very dark or black colour, though there are exceptions to this. These exceptions and slight differences in profiles are due to their diverse distribution. But one thing all Rhoms have is striking red eyes.
Distinctive Features: Red eyes, High back, Large size.
Serrasalmus spilopleura
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+spilopleura
Maximum Size: 12 inches
Body Characteristics: Like with the Rhom, Spilo has many different variations due to their distribution. However usually they are gold or yellow in the lower body and more silverfish yellow the further back you go. However all Spilos caudal fin is lightly coloured with a dark base and has a dark terminal band. Although they have the red eyes like the Rhom, for a serra species their head is quite blunt.
Distinctive Features: Terminal band on caudal fin, Red eyes, Fairly blunt head.
Serrasalmus elongatus
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+elongatus
Maximum Size: 10 inches
Body Characteristics: This is not like any other piranha, its body is very stretched and elongated, hence the name. There are two different colour variants. One has a silvery body, with a dark tail fin and humeral spot. The other has a darker face and fins, orange to red pectoral fins, and traces of red in the lower face and gill plates.
Distinctive Features:Elongated body.
Serrasalmus brandtii
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+brandtii
Maximum Size: 12 inches
Body Characteristics: Normally gold but sometimes purely silver in colour, it have bright iridescent scales on its sides. The fins are normally transparent, the eyes are also colourless and the head is very concave.
Distinctive Features: Clear eyes, Very concave head.
Serrasalmus geryi
http://images.google.co.uk/images?svnum=10&hl=en&lr=&q=Serrasalmus+geryi
Maximum Size: 10 inches
Body Characteristics: They have a very bright shinning silver colour which nearly always sparkles. Unique to geryi is the violet or purple line running from the base of their dorsal fin to the tip of their jaw. The tail fin is dark with a white vertical band in the middle. The eyes are reddish though not completely red.
Distinctive Features: Violet or purple line, Slightly red eyes.