Tagged: evolution

how modern fungi came to be

Phylloporus rhodoxanthus 3

#187: Phylloporus rhodoxanthus, the Gilled Bolete

So, is it an agaric or a bolete? At first glance, the answer seems obvious: it clearly has gills and therefore must be an agaric. However, if you spend enough time around mushrooms you might get a kind of uncanny valley feeling about this mushroom; its coloration, its stature, the way its cap looks somewhat puffy, the way the cap cracks as it dries out, and other subtleties just don’t look quite right for an agaric. When you ignore the gills, the mushroom looks for all the world like a bolete! Phylloporus rhodoxanthus, commonly called “the Gilled Bolete,” is actually closely related to the boletes and evolved gills independently of the true agaric lineages.

Fungi in the News Image 0

2017 Spring News Update

Fungi appear in the news with surprising frequency. However, many of those stories do not provide any new information. Below is a summary of what we’ve learned about fungi from March through April 2017. Read below to learn about: C. auris in the U.S., aflatoxin-destroying corn, viruses defying fungal incompatibility, fungus-farming ant evolution, bat and salamander diseases, and more! Visit the associated links to get the full story.

Fungi in the News Image 0

Mycology News: April to June 2016

Fungi appear in the news with surprising frequency. However, many of those stories do not provide any new information. Below is a summary of what we’ve learned about fungi from November 2016 Through February 2017. Read below to learn about: mycorrhizas, A. bisporus engineering, fungal evolution, psilocybin research, fungal concerns in medicine, rock-eating fungi, and more! Visit the associated links to get the full story.

#078: Evolution of Mycorrhizae 1

#078: Evolution of Mycorrhizae

Arbuscular mycorrhizae have been around since plants began to colonize the land and were probably instrumental in that transition. Ectomycorrhizae and ericaceous mycorrhizae evolved during the time of the dinosaurs and were successful because of their ability to extract organic nutrients from the well-defined soil.  Orchid mycorrhizae were the last to evolve.  This probably happened around the same time as mammal lineages started to diverge.  Despite the tens to hundreds of millions of years of symbiosis, coevolution does not appear to play a large role in the evolution of modern mycorrhizal partners.

#047: Mushroom Morphology: Truffles 1

#047: Mushroom Morphology: Truffles

Truffles are ascomycetes that form below-ground (hypogeous) fruiting bodies. These mushrooms look like small, lumpy potatoes on the outside.  When cut open, truffles have a marbled appearance.  Like the false truffles and sequestrate basidiomycetes, true truffles have evolved to retain moisture in arid climates or other harsh conditions.  Truffles evolved from cup-shaped ascomycetes with a spore surface exposed to the air.  To keep the spores moist, the cup became closed.  Eventually, the interior surface became wrinkled and condensed, creating the marbled interior.  There are a number of truffle species that exhibit various stages along this evolutionary path.  Many of these truffles are hollow on the inside, as the gleba (interior, spore-producing tissue) has not fully become compacted.  All truffles rely on animals – usually small mammals – to dig up the fruiting bodies and eat them.  Truffles attract these animals by producing various scents.  These scents are what give edible...

#045: Mushroom Morphology: Sequestrate Fungi 2

#045: Mushroom Morphology: Sequestrate Fungi

The sequestrate fungi* are an unnatural grouping of mushroom-forming basidiomycetes that have adapted to life in desert areas by keeping developing spores inside the fruiting body. Because of this they are included among the gasteroid fungi.  Like the other gasteromycetes, sequestrate fungi cannot form ballistospores (see FFF#013), and cannot forcibly discharge their spores.  Sequestrate fungi have a stipe and a cap-like head, similar to toadstools.  However, the head never fully opens and the spore-bearing surface remains enclosed by the cap.  The gleba (fertile tissue) does not develop regular gills or pores.  Instead, the gleba forms irregular pockets that are sometimes gill-like in appearance.  This is a highly diverse group of fungi, so there are many variations on this basic structure.  Some sequestrate fungi partially open their caps, while others never do.  Some have reduced stipes and are barely held above the ground.

#033: Mushroom Morphology: Morels 3

#033: Mushroom Morphology: Morels

It’s finally spring in North America! This has been a very long winter, but now the trees are starting to bloom.  To any mushroom enthusiast, this can only mean one thing: it’s the start of morel season!!  Keep your eyes peeled for these elusive mushrooms (especially under Tulip Poplars if you’re on the East Coast)!  What a morel looks like is a little hard to describe without a picture, so look at the one in the link below.  The head of the mushroom is the fertile surface and is defined by an exterior of irregular ridges and pits and a hollow interior.  This is often likened to a pinecone, though one with more color and less regularity.  The head is held above the ground by a stocky, hollow stipe.  The cumulative effect looks somewhat like a pinecone trophy.  There are four main species (or perhaps morphological groups) of morels in...

#010: Fungal Fossils 0

#010: Fungal Fossils

It may surprise you to learn that fungi are reasonably well represented in the fossil record. Most of these fossil fungi are microscopic and lack reproductive structures. Additionally, it is often difficult to infer their ecology, making positive identification difficult, if not impossible.  Fossil fungi are often found inside fossilized plant tissue.  This includes fossils of mycorrhizae, plant pathogens, and wood decomposers.  Many of these finds come from Rhynie Chert in Scotland, which dates to the Devonian period (around 400 million years ago, characterized by small land plants and the first forests).  This is around the same time of the first fossilized land plants.  The fact that mycorrhizae were already well-established by this time suggests that fungi were instrumental in helping plants colonize the land.  The best-preserved fossil fungi are found in amber, often growing on insects.  A mosquito trapped in Baltic amber (from the Eocene period, around 47 million...