Are mine P. multiradiatus or P. paradalis?

[pridecity]

Well, I have been interested in identifying my plecos for several months now. I want to know exactly what species they are because even if two species look about the same, they may have different needs or grow to different sizes. At this time, I'm thinking that my three are all the same species.

I have three named creatively Pleco 1, Pleco 2, and New Pleco. New Pleco has 12 rays in his dorsal. Pleco 2 has 11 rays and Pleco 1 has 13 rays. This leads me to believe that they are one of two species, P. multiradiatus or P. paradalis. They are all roughly nine inches and quickly growing. They have a habit of changing colors (or shades).

I'm almost 100% sure that none of them are "Trinidad" plecos because of the number of dorsal rays. Hypostomus are said to have 8 rays or less and all mine have more than that. This indicates that they are of the Pterygoplichthys order. I just can't decide which of the two they might be. It is either Pterygoplichthys multiradiatus or Pterygoplichthys pardalis.

What do you think?

P. multiradiatus Links:
http://www.planetcatfish.com/catelog/sp ... es_id=1967
http://en.wikipedia.org/wiki/Pterygopli ... tiradiatus

P. paradalis Links:
http://www.planetcatfish.com/catelog/sp ... cies_id=88
http://en.wikipedia.org/wiki/Pterygoplichthys_pardalis
http://www.fishprofiles.com/files/profiles/411.htm
http://www.fishbase.org/Summary/Species ... p?id=25741

And here is the link to my pleco pictures: http://community.webshots.com/album/569 ... =community

[Birger]

I do not think you can rule out

Pterygoplichthys disjunctivus

From the Cat-eLog

This species is most likely to be confused with P. disjunctivus. The pattern on the abdomen is the most useful external key: P. pardalis has a spotted pattern, where P. disjunctivus has a vermiculated pattern.

This has a decent explanation (in case you have not seen it) as it talks about multiradiatus as well.
http://www.planetcatfish.com/cotm/cotm. ... cle_id=366

Birger

[pridecity]

I don't think I saw disjunctivus before. It seems like the more likely of the three. I don't think any of mine are spotted, though on New Pleco, I know him by a circle with a dot in it on his belly pattern. I will have to get pictures taken of each with belly, side, and head. I was thinking that multiradiatus was the least likely, but still possible. Of course, I could very well have one or two of one species and the third is another.

Thank you for that article. It's given me an idea on what sort of tank they will have once I move them to their own tank. Are my conversions right though? The article said a minimum tank of 48"x18"x18". That would be roughly a 67 gallon tank for just one? If that is the case, then the smallest tank I could get for them would be about 210 gallons (giving each 70 gallons). Of course, I was going to get something bigger just in case I decide to rescue a few more from Craigslist.

Also, I read that they like muddier waters. Would that be a brackish tank? If not, how would I accomplish "muddy" without killing filters and still being able to see them some of the time? I want the best for them and knowing the exact species will be helpful just in case by some miracle they want to breed (wait, did I say miracle? I meant bad luck. I'd need to get an even bigger tank! )

[Carp37]

I'd tentatively suggest disjunctivus as well...

[pridecity]

I took some new pictures of all three plecos. I combined a them into two pictures for each pleco. Here they are below.

Pleco 1
http://i42.tinypic.com/alq6g5.png
http://i39.tinypic.com/fbxria.png

Pleco 2
http://i42.tinypic.com/2my9nhz.png
http://i43.tinypic.com/2cr3tlg.png

New Pleco
http://i41.tinypic.com/do01o2.png
http://i43.tinypic.com/2prcqk9.png

Please ignore the horrible graphic layering. I could do better, but saw no point for something that isn't going past this post.

As I said before, I'm leaning towards the disjunctivus, but what is the difference between disjunctivus and multiradiatus?

I found this on http://nas.er.usgs.gov/queries/FactShee ... ciesID=767concerning disjunctivus:

The dorsal pattern consists of light spots that become chevrons posteriorly. The abdominal pattern has dark and light vermiculations of equal width (Howells 2005).