I had name these "Angel Wings" from the 1st foto, but then I see there actually is a fungus with that name. I think these look MUCH more like angel wings but. . . . . I assume these brilliant white fungi start out as spikes but then grow out into flatter fruiting bodies as they grow. The larger of these were probably 4-6 cm tall. I am guessing it could be an anamorph of Xylocoremium flebilliforme, but that is strictly a guess based on the pictures in the guide in the second reference on the right. It is almost certainly a Xylocoremium. I would be very happy if someone could confirm or reject Xylocoremium flebilliforme.
These were found on a downed tree trunk that was 3 meters long and 20-25 cm in diameter on the bank of the Makuma River (650 masl) and above the normal flood line. This section of the Makuma River is in the Amazon rainforest of SE Ecuador.
I saw the white trunk from afar and was amazed to find it nearly covered with this fungus. It reminded me of a heavy frost in NW Iowa. This has to be the most amazing fungus I have seen!
Lat: -2.15, Long: -77.69
Spotted on May 5, 2019
Submitted on May 7, 2019