A mushroom weighing more than 20 kilograms, picked in a forest in Mexico's southernmost state of Chiapas in 2007.

Macrocybe titans, also known as the American titan, is easily the largest fruiting body of the Americas. In a previous Fungi Friday, I wrote about a termite loving African mushroom called Termitomyces titanicus. Like its species name suggests, it too grows incredibly robust. Although they both put out some of the largest mushrooms on the planet, they differ in their ecology. The way each species makes a living differs quite dramatically, so I will remind the reader why directional selection towards larger fruiting bodies has occurred in at least one of these species. Here, I posit a few hypotheses regarding this magnificent American titan. It has too many similarities with the massive Termitomyces titanicus fruiting on the other side of the planet, and although little research has been done on this species ecology, with our mycological understanding, we can begin to put the pieces together.  Macrocybe titans is truly a titan, with some specimens growing an incredible meter across!! If you are completely oblivious and do not see one of these huge mushrooms while you’re walking, you will trip and fall. Not many mushrooms can withstand the stepping of a grown man/women, with 99.99% of mushrooms being easily kicked over. This is speculative, and I have never tripped on this mushroom (no pun intended) but your unaware average human is no match for this monstrosity.