Macrofungi are considered as organisms that form large fruiting bodies above or below the ground that are visible without the aid of a microscope. These fungi include most basidiomycetes and a small number of ascomycetes. Macrofungi have different ecological roles and uses, where some are edible, medicinal, poisonous, decomposers, saprotrophs, predators and pathogens, and they are often used for innovative biotechnological, medicinal and ecological applications. However, comprehensive checklists, and compilations on the diversity and distribution of mushrooms are lacking for South Africa, which makes regulation, conservation and inclusion in national biodiversity initiatives difficult. In this review, we compiled a checklist of macrofungi for the first time (excluding lichens). Data were compiled based on available literature in journals, books and fungorium records from the National Collection of Fungi. Even if the list is not complete due to numerous unreported species present in South Africa, it still represents an overview of the current knowledge of the macromycetes of South Africa. The list of names enables the assessment of gaps in collections and knowledge on the fungal biodiversity of South Africa, and downstream applications such as defining residency status of species. It provides a foundation for new names to be added in future towards developing a list that will be as complete as possible, and that can be used by a wide audience including scientists, authorities and the public.

biodiversity, conservation, macrofungi, Myxomycetes, slimemolds, South Africa, species lists

Macrofungi are fungi that form large fructifications visible without the aid of the microscope and include representatives from the Basidiomycota and Ascomycota (Roda 2010; Servi et al. 2010). Common names used to refer to these fungi include mushrooms, toadstools, cup fungi, gilled fungi, jelly fungi, coral fungi, stink fungi, bracket fungi, polypores, puffballs, earth starts, truffles, and birds nest fungi (Egbe et al. 2013) and illustrates the visibility of these fungi to the public. Ecologically, macrofungi can be grouped as saprobes, parasites and symbiotic species (for instance mycorrhiza). Most terrestrial macrofungi are saprobes or mycorrhizal symbionts, but some are pathogens of plants or fungi, while those fruiting on woody substrates are usually either saprobes or plant pathogens (Mueller et al. 2007; Maria and Tzenka 2014).

Many macrofungi are edible and rich sources of carbohydrates, proteins, vitamins, and minerals for humans (Ananbeh 2003; Gençcelep et al. 2009). They can be naturally harvested or cultivated commercially. For rural communities they serve as a source of protein and income, especially for women. Macrofungi have great bio-exploitation potential in medicine or industry such as in the production of penicillin, lovastatin, and other globally significant medicines, and they remain an untapped resource with enormous industrial potential (Hyde et al. 2019). Mushrooms and other types of macrofungi can grow on decayed organic matters rich in lignin, cellulose, and other complicated carbohydrates, breaking them down for other uses or for bioremediation purposes (Kulshrestha et al. 2014). Modern pharmacological research confirms that large parts of traditional knowledge regarding the medicinal effects of macrofungi are due to proven antifungal, antibacterial, antioxidant, antiviral or other medicinal properties, besides being used as functional foods (Wani et al. 2010). For instance, some of the best known substances present in fungi showing pharmacological properties (especially anticancer and immunological) are polysaccharides (Wasser 2002; Mordali et al. 2007; Zhang et al. 2007; Hyde et al. 2019). Polysaccharides or polysaccharide-protein complexes present in fungi have gained the attention of researchers because it is believed that they can inhibit tumor growth and boost the immune system of the organism. They can enhance host defensive potential or represent biological response modifiers (Leung et al. 2006; Mordali et al. 2007). However, regulation of fungal bio-exploration and research in South Africa is hampered by the absence of biodiversity knowledge.

The fruiting bodies of slime molds or myxomycetes are occasionally observed together with those of macrofungi. The first species was described in 1654 by naturalist Thomas Panckow, who thought it was a species of fungi because of its resemblance to puffballs (Martin and Alexopoulos 1969). Slime molds have two major stages in their lifecycles: a mobile trophic (feeding) and a static fruiting body (reproductive) stage. Modern classifications place them in the Mycetozoan group of Amoebozoa (Baudalf 2008; Fiore-Donno et al. 2010). As bacterivores, slime molds are major components of decomposition and nutrient cycles where they enhance release of nutrients tied up in the microbial biomass (Stephenson and Feest 2015). It is estimated that myxomycete amoebas alone represent more than 50% of the total amoebae for some agricultural soils (Feest and Campbell 1986). Recent studies suggest that more attention should be placed on the use of slime molds as indicators of soil quality.

A small percentage of the 2.2 to 3.8 million species of fungi estimated in the world are currently described and these are mostly in temperate regions (Hawksworth and Lücking 2017). The tropical regions with the highest fungal diversity have not been fully explored (Hawksworth 2001). The reasons for this disparity, even in First World countries, are taxonomic obstacles that are worsened by a paucity of trained mycologists and especially systematists. The low number of published, rigorous, long-term studies on fungal biodiversity also prevents conclusive answers (Mueller et al. 2007). Not even basic questions, such as those related to the number of macrofungal or slime mold species at a specific location, or whether such diversity is greater in one type of forest than in another, can often be answered.

Despite the importance of macrofungi, information on their diversity is scanty, especially in Africa (Osarenkhoe et al. 2014). Thus, due to the lack of human capacities, national monographs of biodiversity in many African countries rarely encompass fungi. This leads to an unfortunate bias in the complete assessment of biodiversity, the unawareness by the public and decision makers of fungi as important components of ecosystem functioning, and frustration from end users at the lack of information (Gryzenhout et al. 2012). Regulation of fungal natural resources and quarantine is thus severely impeded by the lack of lists and information readily available. Not surprisingly, the fungal biodiversity in southern Africa has been relatively poorly studied to date, and no host has been thoroughly treated (Crous et al. 2006; Gryzenhout et al. 2010, 2012). A working checklist will be greatly beneficial to illustrate strengths and gaps in our fungal biodiversity knowledge in South Africa, and will be useful for regulatory authorities.

To address the lack of basic information for macrofungi in South Africa, the aim of this review was to compile a macrofungal and slime mold names list based on current knowledge and resources. We defined macrofungi as having spore-bearing structures visible to the naked eye (mushrooms, brackets, puffballs, false-truffles, cup fungi, etc.). Since slime molds are also readily observed by the public and perceived as fungi (although they do not reside in the kingdom of Fungi), known slime molds from South Africa were also included. Lichens (structures formed by fungi living in close association with algae and cyanobacteria) were excluded from this review because they represent another ill-studied group without solid supportive capacity, but lichen species should be added in future.

The species list was compiled from journal and book publications, and national fungorium records. It is not based on field observations. It is hosted on the website www.themycologyblog.com, which is live and can continuously be refined, expanded and updated. The species list is incorporated by the online resource Cybertruffle’s (http://www.cybertruffle.org.uk/) and the database of the National Collection of Fungi of South Africa (http://www.arc.agric.za/arc-ppri/Pages/Biosystematics/Mycology%20Unit%20(Fungi)/Mycology-National-Collection-of-Fungi.aspx).

The macrofungal checklist compiled in this review (Table 1) presents the first national list for macrofungi and slime molds in South Africa. It includes macrofungal and slime mold species names from previous field guides, other publications, as well as names obtained from the National Collection of Fungi’s PREM fungorium (based on 3597 records), hosted by the Plant Health and Protection (http://www.arc.agric.za/arc-ppri/Pages/ARC-PPRI-Homepage), Agricultural Research Council, South Africa (Table 1). Myxomycete records include 107 species. In total, the South African checklist presented here includes 1160 species, 307 genera and 95 families.