CA Mushrooms

What’s New?

© Else C .Vellinga
Original publication: Mycena News, February 2010

In 2009 two new moss species were described from Yosemite, several southern California lichen species were named (e.g., Caloplaca obamae, Cladonia maritima, Lecanora austrocalifornica, Lecanora munzii, L. simeonensis, and Ramonia extensa), so, what about the mushrooms? Do we have names for all the species we encounter, or are many still nameless?

New species

One new species of mushroom published last year was Pseudobaeospora aphana, a small gilled mushroom that was discovered during the 2007 Mycoblitz at Point Reyes. Pseudobaeospora species are small with subdued colors, often including some lilac, and have white, small, and slightly thick-walled spores (but to recognize them you have to look at really mature spores), which become red-brown when treated with iodine solution. This rather obscure genus has a fascinating history. Up until ten years ago only a handful of species were known. Then, Kees Bas, a Dutch mycologist, examined the two collections in the national herbarium in the Netherlands and compared them to the two known European species. Not only were the two Dutch collections different, but neither fitted any known species. After this shocking discovery Kees asked his colleagues for more material of this now enigmatic genus. He ended up describing 14 new taxa, and some collections were only given provisional names because there was not enough material. One of his discoveries was that some species stain dramatically with KOH – either green or red, or yellow-green, or blue. After this Pseudobaeospora was definitely on the map, and now around 30 species are known and named worldwide. I was fortunate to be working in the room where these discoveries were made, so recognizing a Pseudobaeospora species as such has become second nature.

Recently Dennis Desjardin named another species in this genus. Pseudobaeospora stevensii (named after Fred Stevens), has been found on the Peninsula and in the North Bay. It is one of those KOH-staining species, whereas Ps. aphana is not so distinctive. In other words, the Bay area has gone from zero to two species in this genus in the course of five years!

A new Suillus will be described soon, one that also fruits at Point Reyes, and on Santa Cruz Island, though it is quite widespread. It was discovered not by its fruitbodies, but by the mycelium on the roots of trees. Pine seedlings grown in soil samples from different parts of the state (mountains, coastal regions) were inspected for ectomycorrhiza. DNA was extracted and one part was sequenced and compared with sequences from other Suillus species. Most Suillus species have spores that do not stay viable for long in the soil, but this species is different, and its spores survive the dry soil conditions so prevalent in the state of California. Older Suillus fruitbodies are hard to identify to species, as they all turn orange brown and look disconcertingly similar; DNA data can circumvent this problem; however, as DNA data are only available for a limited set of species, the authors of Suillus quiescens, the species in question, took great care to also compare the new species morphologically with those described previously from California and the southwest. The test was passed and the name quiescens was chosen as the spores lie dormant in the soil.

 That is two new species. How many species of fleshy mushrooms do you think were described altogether in the U.S.A. in 2009? Think for a moment before you read on.

The answer, as far as I can tell, is six, or five if you have trouble accepting a crust as a mushroom. Only one new agaric, the above mentioned Pseudobaeospora, was described in the entire country! Two bolete species were discovered, one in northern Florida along the Gulf coast, and one other southeastern species, known from Virginia to northeastern Texas. Furthermore, two new hypogeous truffles were described, from Iowa, and there was one crust-forming species. Six is a very low number, but it is based on a literature search through thirteen different journals.

To put this in context, I did a quick search in Mycotaxon, an American journal that only publishes taxonomic articles on fungal species, and checked how many mushroom species were described in 2009 from Europe, a mycologically very wellinvestigated region, and from China, a country where a lot of work still needs to be done and many species are in the process of being discovered. Six new species were described from Europe, even though someone in France or the Czech Republic would not pick Mycotaxon as their first choice to publish in. Five new species from China were described, with again, more in other journals.

Of course, these numbers fluctuate very much from year to year. There are already several articles with new species descriptions waiting to be published in Mycologia alone (Mycologia is the s journal of the Mycological Society of America).

The discovery of new species is only part of the work mycological taxonomists do. Unraveling phylogenetic relationships, discovering old names for present collections, and helping identification by providing keys are other facets.

For California as a whole, our knowledge is very imbalanced and incomplete. Some mushroom groups are well studied, recent keys are available, and new discoveries are hard to make. Boletes come to mind as an example of a relatively well-studied and well-known group.

The genus Cortinarius is at the other end of the spectrum, with species that are notoriously difficult to recognize, a complicated literature focusing on European species and keys that mostly rely on macroscopic characteristics for species recognition. Macroscopic characteristics tend to be harder to quantify and describe than microscopic characteristics, and this makes it difficult to compare notes.

A third group is made up of species for which we think we have simply adopted names from Europe or eastern North America. An example is Amanita muscaria, once thought to be all over the Northern Hemisphere, but now restricted to Eurasia and Alaska. ‘Our’ North American Amanita muscaria must be split up in several regional species, but there are no names yet for them. West-coast Amanita franchetii is another one, different from the European, real, Amanita franchetii, but not yet provided with a new, appropriate proper name.

The nice thing about field mycology is that everybody can contribute to the enhancement of knowledge. Collecting, documenting, photographing, and keeping specimens is the first step - and that can be done by all of us!