#146: Gliophorus psittacinus, the Parrot Mushroom

This is a beautiful little waxcap that displays one of the most striking color changes of all mushrooms. Gliophorus psittacinus is easily identified by its slimy texture and bright green color that becomes yellow as the mushroom matures. Because the color fades, older specimens are easily confused with the many other yellowish waxcaps. For easy identification of this mushroom, you really need to find young specimens that are still green and slimy. As with other waxcaps, the flesh has a texture reminiscent of candle wax. However, you’re more likely to notice the substantial slimy coating over the cap and stalk, which obscures the texture of the thin flesh. Because of its initial bright green color (which one might term “parrot green”), G. psittacinus is commonly called the “Parrot Mushroom” or “Parrot Waxcap.” Indeed, the root word in its specific epithet means ‘parrot’ in both Latin and Greek.^1,2

Description

G. psittacinus is a small umbrella-like mushroom with a hemispherical to flat pileus and a central stipe. The mushroom grows to between 1 and 4cm tall and produces a pileus 0.5 to 3cm in diameter.¹ North American West Coast specimens tend to be larger, growing 4-9cm tall and 1.5-4cm across.³ European mushrooms are somewhere between the two with dimensions of 3-6cm tall and 1.5-4cm wide.^2,4

The pileus is the most readily seen and most striking part of the mushroom. It starts out small and hemispherical but expands to become convex or nearly flat. At first, the pileus is very slimy and dark green. Although the color is somewhat variable, most mushrooms start out some shade of green. This color quickly fades, however, and the cap takes on a yellow to orange hue. The fading starts at the center of the cap, so mature specimens often retain some of their green color around the edges. The pileus margin also frequently displays faint lines that trace the gills underneath.^1–3

Underneath the pileus, the mushroom forms gills that start out pale green but become yellowish or orange-yellow as they mature. Exactly when in development this change takes place varies between individuals, so the gills may already be yellow in some young specimens. The gills are attached, although they may run down the stipe some or recede from the stipe slightly. Parrot Mushrooms frequently produce short-gills, which start at the cap’s margin but do not run all the way to the stipe. Despite the gills’ coloration, the mushroom produces a white spore print.^1–3

The stipe supporting the mushroom is only a few millimeters thick and stays roughly the same thickness for its entire length. It is colored and textured like cap. The stipe starts out green and fades to yellow or orange from the bottom up. Older specimens occasionally keep some green at the top of the stipe, but most of the time the stipe fades completely to yellow. As with the cap, the stipe is smooth and quite slimy. Inside the stipe, the flesh is waxy and whitish with tones of yellow and green and surrounds a small hollow area at the center of the stipe.^1–3

Ecology

The Parrot Mushroom can be found in North America and Europe growing gregariously on the ground in a variety of habitats.^1–3 In Europe, the mushroom favors acidic or neutral grasslands that have not been fertilized.² In North America, it prefers forests of either hardwoods or conifers.^1,3 On both continents, it is often found growing in moss and/or along roadsides. G. psittacinus produces mushrooms from spring through fall or over winter in warmer climates.^1–3

Waxcaps are traditionally considered saprobic, but they also seem to have some kind of mutualistic relationship with mosses.^1,2 So far, I have found G. psittacinus in mulch and along a wooded stream bank. Neither of these places had much (if any) moss, so maybe availability of moisture is more important than plant relationships.

Similar Species

G. psittacinus is a rather variable species and may actually be a species group. In North America, at least, it seems likely that multiple species are hiding inside the mushroom’s current definition.^1,5 Mycologists have yet to tease out any of these species, so for the moment they are all called G. psittacinus and the larger distinctions are separated out into varieties.^1,3 European authors recognize three varieties: G. psittacinus var. psittacinus, which is the normal variety, G. psittacinus var. perplexa (sometimes separated out as its own species, Gliophorus perplexus), which does not have any green color at the top of its stipe, and G. psittacinus var. albietina, in which the green tones are more even and longer-lasting.^2,4 North America has a unique variety: G. psittacinus var. californicus (although this name isn’t official due to procedural red tape). This version starts out blue and becomes red as it matures.⁶

Older Parrot Mushrooms can easily be mistaken for many other smallish, yellow waxcaps. This can make them very hard to identify down to species. Frequently, traces of green can be found on the caps of mature mushrooms, which helps simplify identification.^1,2

There are two other species of green-capped waxcaps in North America: Hygrocybe chlorochlora and Hygrocybe virescens. Both species are found in the Caribbean and Mexico and have a stipe that is dry to moist but never slimy. H. chlorochlora has a mostly yellow stipe while H. virescens has a mostly green stipe.⁷

Edibility

G. psittacinus is listed as edible in most field guides, although some label it mildly poisonous.^3,4 Of course, it would take hundreds of Parrot Mushrooms to make a decent-sized dish. Thanks to its small size, rarity, and unappealing texture, nobody bothers to collect and cook this mushroom. In Europe, mycologists go one step further; they recommend against eating G. psittacinus because the mushroom is very rare and they therefore want to discourage collection for consumption.²

Taxonomy

This fungus may be found listed under a few different names because it has been shuffled around between a number of genera over the years. Two common synonyms for G. psittacinus are Hygrocybe psittacina and Hygrophorous psittacinus.^1,2 Hygrocybe and Hygrophorous are the two main genera of waxcaps, so either name would seem reasonable. The mushroom was moved to its current genus in 2013, which means many publications still list it under one of its older names.¹ Among the waxcaps, the genus Gliophorus presumably diverged from the Hygrophorous lineage, making it more closely related to Hygrophorous than to Hygrocybe. However, the evolutionary branches of the waxcaps are not very well defined, so the genus’ exact placement in the lineage is still up for debate.⁵

Kingdom	Fungi
Division (Phylum)	Basidiomycota
Subdivision (Subphylum)	Agaricomycotina
Class	Agaricomycetes
Subclass	Agaricomycetidae
Order	Agaricales
Family	Hygrophoraceae
Genus	Gliophorus
Species	Gliophorus psittacinus (Schaeff.) Henrik8