aka king trumpet mushroom, French horn mushroom, eryngi, king oyster mushroom, king brown mushroom, boletus of the steppes*, trumpet royale, aliʻi oyster
*According to wikipedia, this is misleading nomenclature because boletus (which has pores) and eryngii (which has gills) are of different orders. All I know is that eryngii is delicious and it’s very hard to cook wrong.