I have to be honest, I am a complete sucker for bright colored fruiting bodies. But hey, this goes two ways, right? I mean, you’re the one who clicked the link! Whenever I’m on a fungal foray, species that contrast the dark color of the earth and debris that makes up the forest floor are most welcome. They refresh my senses and keep me wanting more. The fungus featured in today’s Fungi Friday is yet another brightly colored fungal friend, that goes by the name Crepidotus cinnabarinus. This stunner of a species has a saprophytic lifestyle, breaking down large woody debris to attain the carbohydrates and nutrients required to carry out its life cycle.
This species of fungus is actually quite rare, only having nine appearances on the mushroom cataloging site http://mushroomobserver.org . Compared to many other species I write about on this blog, Crepidotus cinnabarinus has a narrower distribution, being found in pine and oak dominated forests in North America. There have been very few observations of this species outside of North America, with a few individuals identified in Denmark. It has a preference for dead basswood and poplar trees and grows in small groups on decently decomposed substrate, revealing its later successional ecology.
Later successional species like Crepidotus cinnabarinus are becoming rarer in this human dominated era, while latently present, primary fungal colonizers have the edge. Because of modern forestry practices, less large trees make their way to the forest floor. In many cases, when they do, they are removed through human intervention. This is why more fungal parasites and early colonizers of woody debris are better off in this human governed epoch also known as the Anthropocene.
Luckily, for now, there are still forests in the United States and Mexico untouched by the lumber industry. It is these ecosystems where we expect to see the most fungal diversity and where we have the best chance to observe Crepidotus cinnabarinus in action. The distribution of this species may be a bit perplexing as the climate of Mexico and the Eastern U.S. is drastically different. Interestingly enough these two regions share much of the same species. If you look at a map, it seems like the Western U.S. flows into Mexico, but there is actually no habitat continuity between these two regions. Oppositely, forest systems from the Eastern U.S. are less fragmented with the forest systems of Mexico, thus resulting in similar species assemblages.
The distribution of this species reveals the importance of habitat connectivity. Crepidotus cinnabarinus grows in the different conditions of Eastern U.S. and Northeastern Mexico. Again, abiotic factors like temperature, moisture and light are not the only drivers of species distributions. These two regions share similar communities of fungi, not because they have similar habitats, but because they are connected by forests. In the Anthropocene, we face more and more habitat fragmentation, which can lead to reductions in ecosystem functioning. Habitat fragmentation most notoriously reduces the dispersal of larger, flightless mammals, obstructed by roads and other man-made constructs. Here, we see an example of how habitat connectivity influences the fungal community. If large sections of forests connecting Mexico with the Eastern United States are removed, we can predict the divergence of two separate fungal communites. If forests remain connected, species like Crepidotus cinnabarinus will show up across the different biomes that make up these two regions.