Armillaria is among the more variable and hybridish genera of fungi, and wood decomposers are an active gene pool to start with. After years of observation, I am still occasionally baffled by an odd-looking Armillaria. I inevitably taste and smell the specimens: fungi are first and foremost beings of contact chemoreception, they respond to the presence of organic compounds, rather than to light, heat, etc. Use your chemoreceptors, that is the best advice I can offer you. Once you are confident in the taste and smell of a mushroom, you can learn to believe the odd variability the fruits display. Also, among many Armillaria, there is an associated black rhizomatous business around the roots it is eating. That will pretty much assure you have a honey.

 

A Armillaria drawing by Melisa Beveridge from California.

 

Here are some images of Armillaria mushrooms. Note the stereotypical structures of the ring on stem, the white spore print, and the gill appearance.

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Armillaria mellea, Armillariella mellella, Honey mushroom, etc etc. It is the cause of shoestring root rot in conifer trees and a very tasty mushroom. The appearance of the fruiting bodies can be widely variable, but they are usually cespitose or at least grouped. The appearance of the scar-like annulus is a sure ID once you are famiiar with it, but remember there are at least 9 separate varieties in North America. Note the attached to even slightly decurrent attachment of the gills. Honey mushrooms are prone to discoloration by weathering: they may be light brown caps with white gills or a uniform tan to dark brown. The scales on the cap are also a good indicator, but I have seen specimens where these were totally washed off by rain.
    These are famous tasty mushrooms revered in Russia, gorged on in Germany, plucked in Poland, unknown in the USA. They can be pickled, fried in butter, used in stews, soups, or sauces. Cook honey mushrooms well, and never eat them raw, as they have caused digestive upset in folks who did. Acquaint yourself with the variability of appearance they display, and enjoy.