Monday, November 15, 2010

Deadly Galerina

Galerina autumnalis
This mushroom is one that I believe it is worth knowing well, specially when one considers its toxicity and the deadly consequences of mistaking it for other mushrooms. Indeed, any amateur mycologist worth its salt should be capable of identifying at least this mushroom and a couple deadly Amanitas, as for instance the Death Cap (A. phalloides) and the Destroying Angel (A. ocreata, A. virosa and A. bisporigera)

The Deadly Galerina (Galerina autumnalis or Galerina marginata (Batsch) Kühner)  is a good example of why mushrooms picking (specially for the table) should be done with great respect. In spite of its small size, a single Galerina can kill an adult (or more). This little fungi contains a deadly toxin (alpha-amanitin) which is highly toxic to the liver and that can also affect kidneys and the brain. Reports of poisoning by G. autumnalis have been made since the beggining of the last century (Peck, 1912). Death occur around 5 days post ingestion if heroic measures (i.e. liver transplant) are not taken and those that survive have increased incidence of liver cancer. Although its identification is quite easy, once could possibly mistake it Psilocybe specie or for honey mushrooms.  Most often Galerinas are found growing on dead/rotten wood.
Note the white mycelium at the base.

Being a gregarious mushroom, one can always find multiple specimens on the same log and it's innocent appearance may even tempt some to taste it (please, don't!). To complicate things a bit, quite often Galerinas grow side by side with Honey Mushrooms (Armillaria gallica). For an example see Tom Volks website, where he has a cool photo showing both mushrooms growing on the same log.
Ring on the upper par of the stipe.
Galerinas are quite easy to identify. They are small (2.5-8 cm of length) wheat colored (Roody calls it yellow-brown to orange-brown). with a hemispheric to convex pileus (cap), which is viscid when moist, smooth and glabrous (bald). The hymenium has close, adnate (attached) gills that are more or less the same color as the cap cuticle. They have a central stipe (stem) that is equal (same diameter from bottom to top) and hollow. The stipe usually has a white ring on its upper part, that often is colored brown due to the falling spores. The stem has longitudinal lines (fibrillose streaking), which are dark brown, and it tends to be lighter at the top than at the base. Last, frequently the stipe is attached to decaying wood by a cottony white mycelium. If you happen to obtain a spore print, the color should be rusty brown.

Notes on this specimen
Date: 11/13/2010
Location: Scott's Run Nature Preserve, McLean, VA
Habitat: Gregarious, growing on rotten wood

Measurements
Pileus diameter: 17.3 mm
Pileus height: 8.3 mm
Stipe length: 40.5 mm
Stipe diameter at base: 3.0 mm
Stipe diameter at middle: 2.7 mm
Stipe diameter at apex: 2.7 mm

Description
Pileus: Convex, round, smooth, glabrous, yellow-brown, margin is dark brown, entire. Smell is non-distinctive.
Hymenium: Gills are adnate, pale brown.
Stipe: Central, equal, hollow, smooth with longitudinal streaking, light brown at top and dark brown at base, white mycelium at the point of attachment, brown ring on upper part of the stipe (10 mm from the pileus).
Spore print: Not obtained


References: Roody WC. Mushrooms of West Virginia and Central Appalachians. Pg 33.

Sunday, November 14, 2010

Last foray of the year

Unindentified mushroom
The winter is just around the corner and the mushroom season is probably almost over. Because  I haven't been going to forays very often (life is hectic when you have a two-year old daughter) I decided to join the last MAW foray of the year at Scott's Run Nature Preserve in McLean, VA. The group was composed of approximately 15 to 20 people and it was a beautiful day, with a perfect blue sky, and pleasant temperatures. 

Pear-shaped Puffball (Lycoperdon pyriforme)
Because it has not been raining a lot and because the temperatures at night are reaching freezing point, there weren't too many mushrooms around, specially in the areas far from the water where humidity is quite low. Furthermore, the leaves have already fallen, and by now most mushrooms are probably hidden under the a thick layer of beige material. In spite of that, a small variety of mushrooms were found, including some Blewitts (Clitocybe nuda), Fawn Mushrooms (Pluteus atricapillus), Deadly Galerinas (Galerina autumnalis), Pear-shaped puffballs (Lycoperdon pyriforme), a couple colorful and bright yellow colored Golden Waxy Cap (Hygocybe flavescens) and a variety of polypores, including the usual suspects: False Turkey Tail (Stereum ostrea), Turkey Tail (Trametes versicolor), Parchment fungus (Stereum complicatum), Thick Mazed Polypore (Daedalea quercina), Cinnabar-red Polypore (Pycnoporus cinnabarinus), one large specimen of what looked like a Stump Blossom (Polyporus berkeleyi) and a large number of Resinous Polypore (Ischnoderma resinosum). All in all, it was a fun foray and it gave me plenty of material to bring home for studying.

Resinous Polypore (Ischnoderma resinosum)
Since I don't expect to be going out on forays before the spring, I'll write about each of my findings over the next couple of weeks and post them in separate posts.

Thick Mazed Polypore (Daedalea quercina)