CLATHRUS ARCHERI: CHARACTERISTICS, HABITAT, REPRODUCTION, NUTRITION - BIOLOGY - 2025

Clathrus archeri is a fungus of the Phallaceae (Basidiomycota) family, with a foul smell and with four to eight arms that resemble tentacles that unfold from the foot. The odor it gives off attracts insects that the fungus uses as a means of dispersing its spores.

It is a saprophytic fungus of Australian origin, but currently distributed in many countries, probably due to accidental introduction by humans during the First World War.

Clathrus archeri. Taken and edited from: Hingel.

The immature fruiting body is egg-shaped and white or pink in color. When mature it extends arms that can vary in number and that resemble the tentacles of a sea anemone. These arms start from a short foot and generally hidden in the volva.

characteristics

The immature carpophorus is egg-shaped a little wider than it is long; the apex is slightly flattened, measuring approximately 3 cm high and 5 cm wide, with a gelatinous consistency and a white to pale pink color, When mature, the carpophorus generally displays four to five arms, although sometimes they can be as many as eight arms, which are well separated and present an intense red color with black spots in most of their extension and pale pink to white in the center..

This carpophor is covered by a dirty white gelatinous layer (peridium) that will form the volva. The foot or pseudo-stipe is very short, white at the base and pink near the arms, generally being hidden by the volva.

The gleba is olive green in color and gives off a foul and unpleasant odor. Basidiospores are elliptical, smooth, and hyaline in appearance. 6 basidiospores are formed per basidium and their size ranges from 6 to 7.5 µm long by 2 to 2.5 µm wide.

Habitat and distribution

The fruiting body of Clathrus archeri emerges during the summer and fall seasons. It develops on soils of moist deciduous forests, being frequent in beech and oak forests, and somewhat less in coniferous forests. It can also grow in wet meadows and gallery forests.

This species is native to Australia or New Zealand and from there it has spread to many countries, mainly accidentally due to human activities. The researchers believe that there were two main sources and forms of dispersion, both located in France.

One of these foci may have been the French district of Saint-Dié-des-Vosges, where the fungus was discovered in 1914 and may have arrived in the form of spores attached to horses and their forage, or to the same soldiers returning to Europe. during the First World War.

Another place of dispersal could have been the French district of Bordeaux, by means of spores attached to imported wool for the textile industries. From these foci it could have migrated in a specific way to different countries, among which are Italy, Spain, Belgium, Holland, Slovakia and Ukraine.

Taxonomy

Clathrus archeri belongs to the class Agaricomycetes of the Basidiomycota, and within this class, it is located in the order Phallales, family Phallaceae. This family harbors fungi that are characterized (among other aspects) by their nauseating smell, which is used to attract insects that help the dispersion of spores.

For its part, the genus Clathrus was described by the Italian botanist Pier Antonio Micleli in 1753 to harbor fungi of the Phallaceae family that had an olive green to brown gleba. This genus has an extensive synonymy, among which are Clethria, Clathrella, Linderia and Linderiella.

The genus currently has more than 20 species, being the type species Clathrus ruber. Clathrus archeri was described by the cryptogamist clergyman and botanist Miles Joseph Berkeley in 1859 as Lysurus archeri.

It was later transferred to the genus Anthurus because its arms are free and not forming a kind of box. Dring made the location of the species in the genus Clathrus in 1980.

Other genera where the species has also been located at one time include Aserophallus, Pseudocolus, and Schizmaturus. It has also been erroneously assigned to the species Asero ë rubra by some researchers.

Reproduction

The reproduction of Clathrus archeri occurs through spores. This species, like the rest of the Phallaceae, lacks a hymenium and the spores will form in the gleba, a gelatinous-like structure that is found on the arms of the fungus.

In Clathrus archeri, this reproduction involves the participation of insects such as flies and beetles, which are attracted by the foul odor of the spore-laden gleba. The insects feed on the gleba and ingest the spores, and these also adhere to the outside of the insect.

Later, when the insect leaves the fungus, it will serve as a vehicle for transporting the spores to new locations.

Immature fruiting body (egg) of Clathrus archeri. Cross-section. Taken and edited from: H. Krisp.

Nutrition

Clathrus archeri is a saprotrophic organism that feeds on decaying plant matter. It is an important soil producer in the localities where it is found, since it degrades the complex carbohydrates that make up the plant tissue, transforming it into simpler substances available to other organisms.

Endangered species or invasive species?

Clathrus archeri is an introduced species in Europe, with a punctual distribution and that is still in the process of settlement in some localities. Despite this, it is a species considered endangered in the Netherlands and Ukraine.

The Netherlands includes the species in the Red List of threatened species and Ukraine in its Red Book. The latter country has even carried out laboratory studies in order to determine the reproductive success of the species cultivated in different types of substrates, as well as to measure the success of the redoculation of the fungus into the environment.

However, some researchers consider it an invasive species. The only factor that seems to condition the dispersion of the fungus in some localities seems to be the calcium content in the substrate, since the species does not thrive in soils with a high content of this mineral.

References

1. Clathrus archeri. On Wikipedia. Recovered from: en.wikipedia.org
2. Phallaceae. On Wikipedia. Recovered from: en.wikipedia.org
3. C. Bîrsan, A. Cojocariu & E. Cenușȃ (2014). Distribution and ecology of Clathrus archeri in Romain. Natulae Scientia Biologicae.
4. M. Pasaylyuk, Y. Petrichuk, N. Tsvyd & M. Sukhomlyn (2018). The aspects of reproduction of Clathrus archeri (Berk.) Dring by re-situ method in the National Nature Park Hutsulshchyna.
5. Clathrus archeri. In Catalog of Mushrooms and Fungi. Fungipedia Mycological Association. Recovered from: fungipedia.org.
6. J. Veterholt, Ed. (1988). Danish Red List of Fungi 2001 - edition. Conservation Committee, Danish Mycological Society. Recovered from: mycosoc.dk.