Entoloma hochstetteri

Description

Entoloma hochstetteri is a species of mushroom that is native to New Zealand. The small mushroom is a distinctive all-blue color, while the gills have a slight reddish tint from the spores. The blue coloring of the fruit body is due to three azulene pigments.

Although many members of the genus Entoloma are poisonous, the toxicity of this species is unknown. It has been investigated to see if its blue coloring might be manufactured as a food dye.

The Ngāi Tūhoe describes that the Kōkako bird (Callaeas wilsoni) got its blue wattles from it rubbing its cheek against the mushroom. Thus giving the mushroom the title of werewere-kokako.

Common names: Blue Pinkgill, Sky-Blue Mushroom, Werewere-Kokako.

Mushroom Identification

1. Cap

   The cap may be up to 4 cm (1.4 in) in diameter and conical in shape. The cap color is indigo-blue with a green tint and is fibrillose. The cap margin is striate and rolled inwards.

2. Gills

   The gill attachment is adnexed or emarginate, gills are thin and 3–5 mm wide, essentially the same color as the cap, sometimes with a yellow tint.

3. Stem

   The cylindrical stem is up to 5 cm (2 in) long by 0.5 cm thick, fibrillose, and stuffed.

4. Spores

   The spores are 9.9–13.2 by 11.8–13.2 μm, tetrahedral in shape, hyaline, smooth, and thin-walled. The basidia are 35.2–44.2 by 8.8–13.2 µm, club-shaped, hyaline, and with two or four sterigmata.

5. Spore Print

   Reddish-pink.

6. Season

   January and July.

History

The species was first described as Cortinarius hochstetteri in 1866 by the Austrian mycologist Erwin Reichardt, before being given its current binomial in 1962 by Greta Stevenson. It is named after the German-Austrian naturalist Ferdinand von Hochstetter.

In 1976 Egon Horak combined Entoloma hochstetteri and Entoloma aeruginosum from Japan with Entoloma virescens, first described from the Bonin Islands in Japan. In 1989 S. Dhancholia recorded E. hochstetteri in India. In 1990 Tsuguo Hongo from Japan examined E. hochstetteri and E. aeruginosum and concluded that they were different taxa, because of the difference in the size of the spores and the shape of the pseudocystidia. In 2008 Horak recognized E. hochstetteri as a different species from E. virescens, while noting that "it is open to speculation" whether taxa such as E. virescens are the same species.

A similar mushroom is found in Australia and mycologists differ as to whether it is E. hochstetteri, E. virescens or a separate species.

Fun Facts

1. Distinctive Appearance

   This mushroom stands out with its vibrant blue coloration, attributed to azulene pigments. The cap is conical, up to 4 cm in diameter, and often has a green tint. Its gills, initially blue but turning reddish due to spores, add to its unique aesthetic.

2. Cultural Significance

   In New Zealand, Entoloma hochstetteri is culturally significant. It features on the New Zealand fifty-dollar note and was also commemorated on a set of stamps in 2002. Known locally as "werewere-kōkako," its Maori name links it to the blue wattles of the kōkako bird in folklore.

3. Taxonomic History

   Initially described as Cortinarius hochstetteri in 1866, it was later reclassified as Entoloma hochstetteri in 1962, honoring the naturalist Ferdinand von Hochstetter. There have been taxonomic debates and revisions over its classification and relationship to similar species worldwide.

4. Habitat and Distribution

   Entoloma hochstetteri is found in New Zealand's broadleaf and podocarp forests, often appearing from January to July. Although reported in India and Australia, its endemic status to New Zealand remains debated.

5. Ecological Role

   As a saprobic fungus, it plays a role in breaking down organic matter in forest ecosystems. Attempts to cultivate it in laboratories have so far been unsuccessful, highlighting its complex ecological niche.

6. Mycological Interest

   The species' toxicity remains uncertain, although many related Entoloma species are known to be toxic. Researchers are exploring its genetic makeup, particularly its genes responsible for the blue coloration, which could have applications in natural food dyes.

7. Variability

   Entoloma hochstetteri exhibits variability in size, color intensity, and habitat preferences. Its cap can range from light to dark blue, sometimes with hints of green, and its appearance may vary depending on geographical location and environmental conditions.

8. Research and Conservation

   Ongoing research aims to clarify its taxonomy, ecological role, and potential benefits. Conservation efforts are crucial due to its cultural importance and potential vulnerability to habitat loss or climate change impacts.

Photo sources:

Photo 1 - Author: Bernard Spragg (Public Domain)

Photo 2 - Author: Bernard Spragg (Public Domain)

Photo 3 - Author: Bernard Spragg (Public Domain)

Photo 4 - Author: Bernard Spragg (Public Domain)