The "Dog Fish" of Brazil

*This is an updated article originally posted on my personal blog in March of 2010.*

The Peixe-Cachorro ("Pay-shee Kah-show-h-oh") or the "Dog Fish" (also known here in Brazil as the Cachorra, Cachorra-facão, Pirandirá and Payara) is a fish that can be found in various rivers in Brazil, including the Rio Araguaia.

Anyone wanna take a guess as to why it's called the "Dog Fish"?

Check out that grill!
 

The first time I saw the Peixe-Cachorro, I freaked. I had been on the river a few days, getting accustomed to the idea of entering the water (where there were plenty of Piranhas)... when the teenage daughter of a friend of ours caught this creature on a late night fishing excursion. It was like something out of a horror movie, as we beheld the creature that emerged from the night - its massive sharp teeth gleaming in the light...

I was pretty sure it must be some sort of cousin of the Scaly Dragonfish I'd seen in the Deep Book ...and my nightmares. Of course, as a child of the '80s I grew up watching weird horror flicks about a giant alligator terrorizing Chicago, and Piranhas entering landlocked towns through overflowing dams, so this might have been more terrifying than need be. Regardless, I firmly decided against entering the water again - ever.

My friends tried to convince me that they never attack humans, and instead feed on crustaceans and small fish (mainly Piranha). It is said that they only occasionally have been known to consume a fish up to 40%-50% of their own body size. Hmm... I routinely do the same thing on all-you-can-eat sushi nights, so that's understandable.


Unfortunately, I didn't have my camera with me that particular night, as the battery was recharging; but later got these pics while on another fishing trip with my husband along the Rio Kuluene, a tributary of the Xingu River.

Although it's the same family of fish, there are apparently a few different variations in body shape & size, as you can see in the pics above versus the pic below. The one below is a good representation of the type of Peixe-Cachorro found in the Rio Araguaia.

According to other sites that I’ve found in Portuguese (there is hardly any info on this fish, in English) there are actually 2 classes of fish known as the "Dog Fish," the Raphiodon Vulpinus and the Hydrolycus. Within the Hydrolycus class of fish, there are 4 species:

• The Hydrolycus Scomberoides can be found in the Amazon River and tributaries above the mouth of the Tapajós River.


• The Hydrolycus Wallacei can be found in the Rio Negro, or Black River, a tributary of the Amazon River; as well as the upper basin of the Orinoco River, along the Venezuelan-Brazilian border and in Columbia.


• Both the Hydrolycus Armatus and...


• ...Hydrolycus Tatauaia can be found in the Amazon basin, basins of the Tocantins River, Capim River Essequibo (Guyana) and the Orinoco River basin.

There is some confusion in the classification, and the Peixe-Cachorro was initially classified as the Family Characidae, but some scientists contend that it is a unique family: of the same family as the Ramphiodom Cynodontinae, or the Raphiodon Vulpinus. Still others claim that this classification is a sub-family among the Characins.

Whatever the class and family, it is known in Brazil as the Peixe-Cachorro, and is quite scary impressive. From what I understand, the noted difference between the Raphiodon Vulpinus and the Hydrolycus is that the Hydrolycus is longer, and has a round black spot behind the operculum.

Peixe-Cachorro photo by Marco Valerio da Costa
 

If anyone can offer additional insight, or help confirm the identification of these fish, I'd be delighted to hear from you. Oh, and sweet dreams! Don't let the Dog Fish bite! ;)

(To enlarge pics, right-click and open in a new window.)