Perplexing Platy Species  9/25/09
I was looking up species of platy fish the other night and ran into a perplexing puzzle.
<Oh?>
I know Xiphophorus is the class platys, variegated platys, swordtails, and hybrids of the three are placed under.
<Indeed. In fact the Swordtails and Platies sold in pet stores are probably all hybrids of one sort or another. To get pure-bred species of either Platy, Variatus Platy, or Swordtail you need get wild-caught fish or fish bred by dedicated hobbyists.>
Yet I ran into terms such as sp, sp., and 35RD which I did not understand.
<The word "sp." simply means "species", and is how scientists describe a specimen that they cannot, for whatever reason, identify to species level.
In some case the animal concerned does indeed belong to a recognised species, but the scientist just wasn't able to make that identification, lacking the tools, skills or materials. If you found a baby fish in a canal somewhere in Mexico, and you recognised it was some sort of Xiphophorus, but it was too young to identify to species level, you'd call it "Xiphophorus sp.". In other situations, you might find a whole bunch of Xiphophorus you weren't able to identify, and though you couldn't name the species, you could tell that there was more than one species there. In this case, you'd call them "Xiphophorus spp.", meaning Xiphophorus species plural. In other instances, the "sp." or "spp." refers to the fact that these are new species, but you haven't formally identified them. While hobbyists might assume it's quite easy to name a new animal should you discover one, it's actually quite hard work. You have to carefully check the animal hasn't been discovered before, in particular taking care that the thing was reported decades ago and subsequently forgotten about because the description was published in an obscure or foreign language journal. You have to make sure you new animal isn't just an odd version of a familiar species; for example genetic mutations and physical damage can cause animals to look different to other members of their species. And
you'd be surprised how often male and female animals of the same species accidentally got described as different species! The whole process often takes years.>
One species that was listed was listed as Xiphophorus sp 35RD. Now here is where things really got confusing for me. What species of platy is Xiphophorus sp 35RD?
<It's a species of Xiphophorus known to be distinct, but as yet, not formally identified. Because the tropical fish trade often handles newly discovered fish soon after discovery, such fish appear in the shops before scientists give them formal names. So fish exporters give these fish temporary names, in this case, Xiphophorus sp. 35RD. I have no idea what the "35RD" stands for, but it's probably a collecting site or some such.>
Where was it found?
<Mexico, I'd imagine.>
Is it simply an outdated name of another platy, or is this its actual species name?
<It's a "placeholder name" until the fish gets a proper scientific name.
It's analogous to the L-number system used for catfish, where for example the species traded as L001 eventually became Pterygoplichthys joselimaianus.>
What does sp. and sp mean? I know sp. and sp can refer to a species name sometimes. But it does not say when sp or sp. is listed what species to which it is referring. Is it the southern platy, the swordtail, the variegated platy?
<None of the above.>
It simply does not say. And sp and sp. can also mean other things as well.
And what in the world does 35RD mean? Xiphophorus sp 35RD has a taxonomic number, but that is all the information I was able to get. Other than it is a member of the Xiphophorus family.
<Xiphophorus is a genus, not a family. The family is Poeciliidae. In any case, all Xiphophorus are very similar in terms of requirements: relatively cool water, around 22-24 C, hard, basic water chemistry. They're all herbivores, so an algae-based flake food is required. Some come from fast flowing waters (Swordtails) but most come from still water habitats; looking at the body shape is a clue here. If they're streamlined, they like fast water, if they're dumpy, like a Platy, slow-flowing water is better.>
If you have any more information on this species, or better yet a picture, please let me know.
<Not aware that Xiphophorus sp. 35RD is traded yet; certainly never seen a picture. But I can be fairly sure it's small, green, with an upturned mouth and a modest degree of sexual dimorphism -- like all the other (wild-type) members of its genus. Cheers, Neale.>

Mollies and Platies and Swords, Oh My! - 04/20/2006 Hello WWM Crew, <Hi, Chad!> I've just spent much time scrolling through your pages on mollies, platies, and guppies.  Found lots of useful info on breeding, feeding, treating, what do to with fry, and sexing... but can't find - maybe I missed it - an answer to my question.  Is there a way to tell a molly from a platy from a female swordtail? <Sure....  though differences may seem subtle until you've seen many of all.> I have a Mickey and a twin-bar, both platies as I believe they're the only ones colored this way.   <Can find some Mickey mouse swords, now, too.> A few days ago I bought an all-white one and an all-red one.  They were labeled mollies at the pet store, but who knows if they even know.  They are all getting along and all look similar, if you ask me, except maybe for the fact that the new ones are slimmer, especially the red one, but it's smaller altogether.  I've seen pictures online of all-red platies, mollies, and swordtails.  Haven't seen an all-white platy yet. <Hmm, where to start, and how not to make it more confusing....  Platies and swords have been heavily hybridized with one another over the years; you will be very hard-pressed to find a platy that hasn't been crossed with a sword or vice verse somewhere down the line.  Some platies even develop small "swords" on their tails.  Mollies aren't hybridized with either of these, and are usually very easy to tell apart.  They'll have sort of....  well, a different body shape....  kinda tough to describe.  I would recommend that you go to a few different fish stores and look long and hard at some of each of these types of fishes; you'll develop an eye for it in no time.> Thanks for your time. <Glad to be of service.> -Chad Soucie <All the best to you,  -Sabrina>

Xiphophorus maculatus I was on the site looking for what kind of fish I had and I think this might be it Xiphophorus maculatus.  What is the non-scientific name of these fish? <It is a platy, many different varieties.  check out http://fishbase.org > I also believe that mine could be pregnant from the fish store. How can I be sure my fish is pregnant? What signs can I look for? <It is very possible that it is pregnant, a bulging belly is a good sign.  Careful though, if the scales are protruding from the body and it looks a little like a pine cone, it could be dropsy.  Check out the links below. -Gage http://www.wetwebmedia.com/FWSubWebIndex/poeciliids.htm http://www.wetwebmedia.com/AqBizSubWebIndex/fishdisho.htm

Platies I recently bought a few platies and I was wondering how you tell the difference between the male and females. <normally the males are more colorful and have larger more attractive fins. the females are more drab in their coloration and have short fins. IanB> thanks <<Mmm, and as livebearing toothed carps with internal fertilization, the males have modified anal fins (the one underneath their bodies, behind the "belly"). On males these are tube-shaped and on females they're fan-shaped in profile. RMF>>

Mickey Mouse spots Hi Crew! You rule! <Wow!  Thank you.> I have a red female Mickey Mouse molly who is about 8 months old. <Umm, do you perhaps mean a Mickey mouse platy?  I don't think mollies come with that particular pattern.> The Mickey mouse shaped spot on her tail has been getting blurrier as she grows. When she was young, the spot was much clearer. Is this normal? <Yes, quite.  Many fish gain or change color as they age, it is nothing at all to worry about.  Wishing you well,  -Sabrina.>