Endospore confusion

[mysticshadow]

So we were given unknowns a weeks or so ago and were able to run tests to determine what our tubes contained. Our unknowns could be 1 of 25. I know for a fact which unknown I have but I got a confusing result. I have Mycobacterium smegmatis however, I did an endospore stain and it came up positive.

Can anyone tell me why a Mycobacterium smegmatis would appear to have endospores?

Any help would be appreciated. Thank!

[Cat]

How do you know that you have Mycobacterium smegmatis? It is not endospore forming.

[mysticshadow]

I know that I have the correct bacteria because I did all the tests needed to determine which one I had. I had narrowed it down to 3 bacteria and planed to do an endospore stain next. My teacher told me that I could also do the acid fast stain, however he wouldn't let us actually carry it out. So he drew what I would see under the microscope. Which narrowed it down to 1, but to be on the safe side I did the endospore test anyway. He then told me that I made a big mistake and was going to be confused with what I would find.

So I know which bacteria I have, I had already determined that, and I know what I see aren't really endospores, but it still doesn't explain what they really are...