The Spotted Cachorro is a member of a specialized group of piscivoric characins which live in the tropical rivers of South America.

Their appearance is somewhat elongated and tetra-like, with a long snout full of canine teeth. These teeth are nearly transparent and can be easily seen, even when the mouth is fully closed. All fins are triangular and taper to a point, giving the fish an almost stealth-like appearance.

Cachorros are among the most beautiful of all freshwater fish and easily rival marines in color. The Spotted Cachorro is a good example of this beauty. The tiny, fine scales reflect a dark silver-gold from above which fades in layers to a deep fluorescent blue then to a pink-violet, and finally the belly is a translucent white. The fins have distinct orange-gold markings, and the cadual fin is usually more brilliant with an almost red tang to it. Their is two jet-black ocellatus marks on the fish; one just behind the gill plate, and one just behind the caudal penduncle. These two markings are centered in the middle of the fish, and are perfectly aligned with each other. Overall, this fish is incredibly shiny and can even reflect faint dots of light in the aquarium. When the lay person first sees a Cachorro, the image that comes to mind is a deep sea viperfish.

The teeth of Cachorros are not used for grasping, holding, lacerating, or chopping prey. They are used to lock a prey item in the mouth, much like the bars of a jail cell. Usually the teeth never penetrate the prey item. Once the prey is secured in the mouth, the Cachorro quickly swallows it, and a most peculiar thing happens; you can see the victim through the slightly transparent sides of the fish. After several hours of digestion, the area where the prey item could be seen, now turns a dark grey. After a day or so, there is no trace of the victim. Cachorros hunt by catching a live morsel in their mouths after a chase which usually doesn't last long.

Despite the Cachorros amazing hunting and eating abilities, this should not be the prime reason for keeping them, for they can be an expensive hassle. Among the most delicate and sensitive of fish, Cachorros are easily extinguished from life and must be handled with more care than a shard of glass the thickness of a needletip. Therefore you must take special precautions like catching the fish in a plastic bag, and keeping it in utter darkness during times of stress. ALL specimens are imported, and ALL have had their share of stress and abuse. Most are suffering from severe scale damage, shredded fins, disease, and many other physical and mental ailments. Once you receive your Cachorro it will have been through hell. You will have to place it in a quarantine or hospital tank in order to nurse it back to health. This means plenty of stress coat, and absolute darkness for about a week. This is done by wrapping a thick sheet of paper around the tank with a peephole which will be made bigger and bigger over time until the Cachorro gets used to external movement, and lighting. Many frown on the idea of buying sick fish and nursing them back to health, but this is the only way to keep Cachorros. By far this is the worst, and trickiest stage of owning these living jewels.

Once these fish have settled in, and gotten used to aquarium surroundings, you can release them into your main tank. This tank should be of an appropriate size, nothing less than 55 gallons. Keep the water clean and moving, for these are river fish and prefer aerated water. They are sensitive to water changes, so let your water age before introducing it. Neutral to slightly acid water with a temperature between 78 - 82 degrees F. is preferred. For food, you will have to feed them live fish (no more than 1/3 the size of the Cachorro) for they will not except anything else. After a big meal, allow a few days of fasting. Cachorros of the same size get along well together, providing security and companionship. Species such as Ctenolucius hujeta (Freshwater Barracuda) and Boulengeralla maculata (Spotted Pike Characin) also make excellent companions, and to see all of these exotic fish in one healthy aquarium in loose schools is a breath-taking sight. Cachorros are aggressive and can keep their own ground, but their frail body cannot support constant entanglements with other aggressive fish such as Oscars or other large cichlids. If you must keep a Cachorro with something just as aggressive make sure that other fish is smaller, but not too small or you will see it inside the Cachorro the next day!

There are about a dozen species of Cachorro (Acestrorhynchus), some more colorful than others, but all represent a group of fish that are rare, expensive, sinister, and beautiful all in one. If you achieve this fish, it is living gold. Treat it this way, and it will be an experience in the hobby like none other.