Silver Dollars: Metynnis argenteus vs. Metynnis hypsauchen

fashionfobie

Metynnis argenteus vs. Metynnis hypsauchen

I am still a little unsure the difference between these two species. I have researched lots of sites and I am still finding conflicting information. I did read the information on this site as well but I would like to know more.

Does Metynnis argenteus have the red anal fin ?

How do you distinguish the difference when they are young? or is the color present throughout its life?

I seem to prefer the fish with the splash of red but considering how frequently these guys are labeled incorrectly I want to be 100% sure of what I am getting.

I have a 55 gallon set up and I know these are what I want. I find them so adorable and beautiful, the prefect combo. I am planning on getting 5. My tank is about 3 years old and I have really been pondering where I want to go with it. I have a school of 6 Panda Corydoras keeping the up the place :) The big delay is probably due to the fact that I have always had a soft spot for pacu, but they are not really appropriate for me since they will get so large and need a multi hundred gallon tank. These silver dollars, being relatives of pacu, seem like a perfect choice for me and I am very anxious for more feed back on distinguishing the difference between these two species.

Thank you very much,
Natalie

Byron

The distinguishing feature (the shoulder patch) between these two species is mentioned in the first paragraph under "Discussion" in our profile of Metynnis hypsauchen, and there is a photo of each species.

The red colour of the anal fin is sometimes, but not always, present in males of Metynnis argenteus. I note it is present in the fish in the photo in the profile.

I don't know how mature the fish has to be before the shoulder patch is noticeable, but I would expect it to be darker in young fish. If anyone here has maintained this species, perhaps they could comment.

Byron.

fashionfobie

Thank you for your post, I missed that bit about shoulder patch. I am very happy to find out that both have the potential to present the red anal fin. I found a breeder who works with Metynnis hypsauchen. I am very excited to prepare my tank. Java Fern and Anubias here we come ;)

Again thank you,

Natalie

Byron

Just to clarify, I believe the "possible" red anal fin in the male is only in M. argenteus. B.

fashionfobie

wow I seem to be mis-computing today. I will blame it on my french mind