Much of the time, the occurrence and distribution of fungal species makes sense. For example, the mycorrhizal fungi Lactifluus volemusfruits in warm temperate forests throughout the Eastern U.S. and Europe where the trees it forms mutualisms with are active and plentiful. Other times, a species distribution is perplexing to say the least. The fungi featured today is one of the rarest species on Earth. Chorioactis geasteralso known as the devil’s cigar is peculiarly only found in select counties in Texas, and a handful of locations in Japan.
Chorioactis geaster distribution.
Chorioactis geaster distribution.
The ascomycete fungus is quite unique looking, which also made it difficult to classify when it was first found in 1893. Immature club shaped fruit bodies emerge from nearby woody debris on the forest floor. These hollow cigar shaped fungi then split open into 4-7 rays, revealing their spore bearing surfaces. Like other cup fungi, there is a mass spore discharge event that resembles smoke puffing out of the fruit body. This is caused by sudden changes in humidity, and can be induced by blowing a rapid jet of air on the fungus from your lungs. You need to try this the next time you find a cup fungus.
Chorioactis geaster found by Jared McRae.
I really don’t have a hypothesis regarding the odd, isolated distribution of this species. The one geographical detail that does add up is the fact that these two locations on the opposite sides of the planet occur at very similar latitudes. At these similar latitudes, these species experience nearly identical annual photoperiods.
Although it looks like gasteroid fungus, Chorioactis geaster is without a doubt an ascomycete.
In 2004, researchers looked compared the genomes of both Texan and Japanese populations. Utilizing molecular clock techniques, these scientists estimate that these populations diverged around 19 million years. So basically 19 million years ago, spores from one location made their way to the second location. With this information, we know that humans didn’t spread the species to the second location, since Homo sapiens has only been walking the Earth for 200,000 years.
I look forward to someday finding this species. As soon as I learn how rare a species is, it immediately enters my book of bucket list species. This bucket list continuously grows, the more species I learn about.
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