Butterfly pleco

[Silverbc3]

So I went on a fish trip last weekend and most places that I visited had what they called "Butterfly plecos". Now I ain't no expert but when I took a look at it I instantly knew it was not a pleco. I researched it and found out it was a Hillstream Loach. I still ended up purchasing a couple because they looked pretty interesting and I know someone who might want one. It does kind of bother me that the stores can't get their names correct. There was one pleco I noticed which reminded me of the LDA31, mustard spot pleco except it was white spots, anyone know what it might be? I couldn't seem to find it in my aqualog book.

Bert