Joe said:
I noticed that MatchMaker says zelleri "flesh stains greenish with application of NH4OH." So if the cap flesh isn't green already, you might try cutting the cap to expose the cap flesh, then applying some household ammonia.

Don said
This looks to be what used to be called Boletus zelleri, but is now being called Xerocomellus atropurpureus.

If it was mirabilis the cap would be distinctly velvety, whereas this one looks to be more bumpy than velvety.

Noah told us that what we used to call zelleri is actually more rare than we used to think, and that most of what we thought was zelleri is actually atropurpureus.

Both are said to be delicious though……….