Tag: fungus

New species of fungus sticking out of beetles named after the COVID-19 quarantine

A major comprehensive study on Herpomycetales and Laboulbeniales, two orders of unique ectoparasitic fungi associated with insects and other arthropods (class Laboulbeniomycetes) in Belgium and the Netherlands was published in the open-access, peer-reviewed scholarly journal MycoKeys.

A major comprehensive study on Herpomycetales and Laboulbeniales, two orders of unique ectoparasitic fungi associated with insects and other arthropods (class Laboulbeniomycetes) in Belgium and the Netherlands was published in the open-access, peer-reviewed scholarly journal MycoKeys.

Having surveyed arthropod fauna using pitfall traps and an illuminated white screen at night, and with the help of a network of entomologists, Dr. Danny Haelewaters (Purdue University, University of South Bohemia and Ghent University) and Dr. André De Kesel (Botanic Garden Meise) provide identification details about a total of 140 fungal species. The list includes nine species that are reported for the first time for either of the two countries and two newly described species.

Interestingly, one of the novel fungi was described during the 2020 global quarantine period, imposed to curb the COVID-19 pandemic. This prompted the researchers to dedicate the newly discovered species to this extraordinary time. In the annals of science, the species will be going by the name of Laboulbenia quarantenae.

Laboulbenia quarantenae grows externally on the body of ground beetles belonging to the species Bembidion biguttatum and is thus far only found at the Botanic Garden Meise in Belgium. This new fungus is considered to be very rare compared to Laboulbenia vulgaris, another, well-documented species that is more commonly found on the same host. So far, there has been no evidence that L. quarantenae parasitizes other host species.

Extreme close-up of the thalli of a fungus in the genus Hesperomyces (H. virescens sensu lato) parasitizing a harlequin ladybird (Harmonia axyridis).
Image by Gilles San. Drawing by André De Kesel.

Herpomycetales and Laboulbeniales–unlike common mushrooms–do not form branching thread-like hyphae, nor a mycelium. Rather, they grow a single three-dimensional thallus of a few thousand cells sticking out of the body of the host organism. While some species of Laboulbeniales, like Laboulbenia quarantenae, are superficially attached to their host, others are more invasive, such as Hesperomyces halyziae, the second fungus newly described in this study. These fungi produce a haustorium, which is a hyphal outgrowth used to penetrate the tissues of their arthropod hosts, so that they can reach to the primary body cavity and the circulatory fluid in there. By doing so, it is thought that the parasites can both increase surface area for nutrient uptake and tighten their grip on their host.

In their study, the scientists hypothesize that, because of their invasive nature, these haustorial parasites maintain close interactions with their hosts in a process referred to as an “evolutionary arms race”. This means that whenever the host evolves a defence mechanism against the fungus, the parasite promptly evolves in its own turn, and adapts accordingly. Eventually, specialization leads to the evolution of new species.

The present study compiles all available data from Belgium and the Netherlands and serves as an appropriate starting point for an updated checklist of thallus-forming fungi in the class Laboulbeniomycetes found across Europe. Such a checklist is an ongoing project meant to summarize decades of research and will undoubtedly continue to uncover significant fungal diversity. The last update of this piece of knowledge dates back to 1991.

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Original source:

Haelewaters D, De Kesel A (2020) Checklist of thallus-forming Laboulbeniomycetes from Belgium and the Netherlands, including Hesperomyces halyziae and Laboulbenia quarantenae spp. nov. MycoKeys 71: 23-86. https://doi.org/10.3897/mycokeys.71.53421

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Follow lead author Dr. Danny Haelewaters on Twitter (@dhaelewa) and visit his website at: https://www.dannyhaelewaters.com/.

New family of fungi threatens a UNESCO-listed 8-century-old cathedral in Portugal

The Old Cathedral of Coimbra [right], the Santa Maria chapel [left, top] and the artwork from which the scientists retrieved the studied fungi [left, bottom]. Photo by Miguel Mesquita.
To be listed as UNESCO World Heritage requires special care and protection of valuable cultural monuments and pieces of Art from threats such as biodeterioration caused by microcolonial black fungi. The culprits lodge their branch-like structures (hyphae) deep into the stone forming fissures and cracks and also produce polysaccharides that trigger corrosion.

These fungi are well known for their unique resistance to hostile environmental conditions, including extreme temperatures, high solar and UV radiation, severe droughts and low abundance of nutrients. As a result, they survive in hot and cold deserts, saltpans, acidic and hydrocarbon-contaminated sites and exposed rocks surfaces. All of this makes them a particular challenge to conservationists and biologists who care for historic monuments.

During a multi-disciplinary scientific survey at the 8-century-old cathedral Sé Velha de Coimbra (Old Cathedral of Coimbra), which is the only Romanesque cathedral in Portugal to have survived relatively intact since the Reconquista times, scientists retrieved a peculiar slow-growing microcolonial black fungus.

What João Trovão of the University of Coimbra (Portugal) and his colleagues were looking at turned out to be a species of a whole new family (Aeminiaceae) in the order of the sooty mould fungi. The new species, its new genus and the novel family are described in the open-access journal MycoKeys.

This is a colony of the newly described black fungus species Aeminium ludgeri. Photo by João Trovão.

To define the new group of fungi, the researchers first scraped off samples from a deteriorated limestone artwork in the “Santa Maria” chapel and then conducted an extensive and integrative analysis, based on morphological, physiological, ecological characters and DNA sequences.

As for the origin of the previously unknown fungus, the scientists hypothesise that the species had ‘arrived’ at the Old Cathedral of Coimbra with the limestone used during its construction. Coming from the unique nearby areas of Ançã and Portunhos, such limestone has been used on several of the “Our Ladies of the O” statues, as well as in the portal of the Royal Hospital in Santiago de Compostela (Spain). Currently, these fungi are considered endemic to the limestone quarries in the Iberian Peninsula.

“Regarding stone monuments exposed to the environment, microcolonial black fungi are considered one of the main culprits for the phenomenon of stone biodeterioration, being responsible for severe aesthetic, biochemical and biophysical alterations,” comment the scientists.

“It is, therefore, crucial to gather deeper knowledge regarding their biodiversity and their biological, ecological and physiological unique characteristics, in order to span our knowledge regarding these fungi and, at the same time, allow the development and improvement of tools to protect stone monuments from their deteriorative effects.”

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Original source:

Trovão J, Tiago I, Soares F, Paiva DS, Mesquita N, Coelho C, Catarino L, Gil F, Portugal A (2019) Description of Aeminiaceae fam. nov., Aeminium gen. nov. and Aeminium ludgeri sp. nov. (Capnodiales), isolated from a biodeteriorated art-piece in the Old Cathedral of Coimbra, Portugal. MycoKeys 45: 57-73. https://doi.org/10.3897/mycokeys.45.31799

Top 50 most wanted fungi: New search function zooms in on the dark fungal diversity

There are many millions of undescribed fungi, and public DNA sequence databases contain thousands of fungal sequences that cannot be assigned to any known fungal group with confidence. Many of these sequences have defied robust taxonomic assignment for more than 10 years.

Frustrated at this situation, an international group of researchers presents a search functionin the UNITE database for molecular identification of fungi. Its aim is to highlight the fungi we know the least about, and invite the scientific community to resolve their taxonomic affiliation. The effort seeks to bridge the substantial knowledge gap between fungal taxonomy and molecular ecology through a list, the authors refer to as the “50 Most Wanted Fungi”. Their work is presented in a new research paper published in the open-access journal MycoKeys.

Some 100,000 species of fungi have been described formally, although current estimates put the number of extant fungal species to at least 6 million. There is clearly no shortage of research venues in the study of fungi – but are there other shortages? The vast dark fungal diversity unravelled with molecular techniques hints that the interaction between fungal taxonomy and DNA sequencing of environmental substrates such as soil and water is not necessarily optimal.

“There is no taxonomic feedback loop in place to highlight the presence of these enigmatic lineages to the mycological community, and they often end up in sequence databases for years without attracting significant research interest,” explain the authors. “More than 10 years in some cases, as a matter of fact.”

Therefore, the researchers, led by Dr Henrik Nilsson, University of Gothenburg, now present a search function that produces lists of approximately genus-level clusters of fungal DNA sequences whose taxonomic affiliation we know next to nothing about. These lists are recomputed on a monthly basis, accounting for any updates and additions contributed by the scientific community in between each iteration. Community participation is encouraged, and the UNITE database has extensive support for third-party annotation.

By putting the spotlight on these fungal lineages, Dr Nilsson and colleagues hope to speed up the study and formal description of the underlying species. To support researchers focusing on select groups of fungi or environments, a set of keyword-filtered lists is provided. This allows researchers to zoom in on unknown fungi recovered, for example, from the built environment or aquatic habitats.

Commenting on their choice of a name for the list, the researchers clarify that the underlying fungi are not guilty of any crime. “Indeed, nothing can be said of the way they make a living. It is simply not known. We make no claim as to the importance of these fungi from whatever point of view – ecological, economic, or otherwise,” they stress. “We do make claim to their uniqueness, though, because it is frustrating, in the year 2016, not to be able to assign a name to a fungal sequence even at the phylum level.”

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“We hope that the present publication will serve to put the spotlight on these uncharted parts of the fungal tree of life, and we invite the reader to examine them through our online tools or otherwise,” they conclude.

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Original source:

Nilsson RH, Wurzbacher C, Bahram M, Coimbra VRM, Larsson E, Tedersoo L, Eriksson J, Duarte Ritter C, Svantesson S, Sánchez-García M, Ryberg M, Kristiansson E, Abarenkov K (2016) Top 50 most wanted fungi. MycoKeys 12: 29-40. doi: 10.3897/mycokeys.12.7553