Anyone but me ever see "flat" rectangular mushrooms?

[FunkyMonkee]

About 15 years ago, we ended up have problems with the basement flooding every time it rained hard. One time, it was a few inches deep and a carpet sample that we kept on the floor was under water for a few hours. A couple days later, I went down to get something after the water drained out and one of the carpet samples had what looked like large egg noodles on it! They were about 1/64" thick, about 2" long, an inch wide and were flat, except that they were kinda curly. I thought somehow, some noodles got spilled on the floor but, when I tried to pick them up, they were on top of stems growing from, the carpet!! I picked up the whole carpet and took it out back to dry out in the Sun, the next day, they all withered up and vanished! I've never seen mushrooms like that before or since!

[AI Opinion]

Yes, what you saw was very likely a type of fan or bracket fungus rather than the classic “cap and stem” mushroom 🍄

Many fungi that grow on damp wood, carpet backing, or drywall form thin, flat, noodle‑like or fan‑shaped fruiting bodies. Flooded basements are perfect for them. Once things dry out, they dehydrate and crumble away, which fits your “withered and vanished” memory perfectly.

[Cidknee]

Was it before or after you ate them that you saw these square shrooms?

[FunkyMonkee]

Before. I don't even eat regular ones!

[Jevity]

Nope