Fungi play vital roles in ecosystems as endophytes, pathogens and saprobes. The current estimate of fungal diversity is highly uncertain, ranging from 1.5 to 12 million, but only around 150,000 species have been named and classified to date. Since the introduction of DNA based methods for species identification, the number of newly described taxa has increased from approximately 1000 to around 2000 yearly. This demonstrates the importance of DNA based methods to identify and distinguish species, especially cryptic species. Many novel species from recent studies have been found in historically understudied regions and habitats, but these still represent only a small percentage of the estimated species. In this paper, we examine 16 genera from the top 40 most speciose genera as listed in Species Fungorum as case studies to examine the diversity of taxa in each genus. The genera treated herein are Cercospora, Diaporthe, Meliola, Passalora, Phyllachora, Phyllosticta, Pseudocercospora, Ramularia (ascomycetes) and Cortinarius, Entoloma, Inocybe, Marasmius, Psathyrella, Puccinia, Russula, Uromyces (basidiomycetes). We critically evaluate the number of species in these genera and correlate these numbers with the number of entries in GenBank. We introduce 18 new species Apiospora multiloculata, Candolleomyces thailandensis, Cortinarius acutoproximus, Cortinarius melleoalbus, Cortinarius pacificus, Cortinarius parvoacetosus, Diaporthe guizhouensis, Entoloma pseudosubcorvinum, Inocybe meirensongia, Marasmius albulus, Marasmius obscuroaurantiacus, Meliola camporesii, Phyllachora siamensis, Phyllosticta doitungensis, Picipes yuxiensis, Pseudocercospora vignae, Puccinia maureanui and Russula inornata. We also introduce a new record of Candolleomyces cladii-marisci and Inocybe iringolkavensis. We discuss the genera Colletotrichum and Pleurotus that are speciose, but do not occur in the top 40. We hypothesize whether there might be more species in these genera and discuss why these genera have some of the largest number of species.

The recent realistic estimate of fungal numbers which used various algorithms was between 2.2 and 3.8 million. There are nearly 100,000 accepted species of Fungi and fungus-like taxa, which is between 2.6 and 4.5% of the estimated species. Several forums such as Botanica Marina series, Fungal Diversity notes, Fungal Biodiversity Profiles, Fungal Systematics and Evolution—New and Interesting Fungi, Mycosphere notes and Fungal Planet have enhanced the introduction of new taxa and nearly 2000 species have been introduced in these publications in the last decade. The need to define a fungal species more accurately has been recognized, but there is much research needed before this can be better clarified. We address the evidence that is needed to estimate the numbers of fungi and address the various advances that have been made towards its understanding. Some genera are barely known, whereas some plant pathogens comprise numerous species complexes and numbers are steadily increasing. In this paper, we examine ten genera as case studies to establish trends in fungal description and introduce new species in each genus. The genera are the ascomycetes Colletotrichum and Pestalotiopsis (with many species or complexes), Atrocalyx, Dothiora, Lignosphaeria, Okeanomyces, Rhamphoriopsis, Thozetella, Thyrostroma (relatively poorly studied genera) and the basidiomycete genus Lepiota. We provide examples where knowledge is incomplete or lacking and suggest areas needing further research. These include (1) the need to establish what is a species, (2) the need to establish how host-specific fungi are, not in highly disturbed urban areas, but in pristine or relatively undisturbed forests, and (3) the need to establish if species in different continents, islands, countries or regions are different, or if the same fungi occur worldwide? Finally, we conclude whether we are anywhere near to flattening the curve in new species description.

A large amount of agro-industrial waste is produced worldwide in various agricultural sectors and by different food industries. The disposal and burning of this waste have created major global environmental problems. Agro-industrial waste mainly consists of cellulose, hemicellulose and lignin, all of which are collectively defined as lignocellulosic materials. This waste can serve as a suitable substrate in the solid-state fermentation process involving mushrooms. Mushrooms degrade lignocellulosic substrates through lignocellulosic enzyme production and utilize the degraded products to produce their fruiting bodies. Therefore, mushroom cultivation can be considered a prominent biotechnological process for the reduction and valorization of agro-industrial waste. Such waste is generated as a result of the eco-friendly conversion of low-value by-products into new resources that can be used to produce value-added products. Here, we have produced a brief review of the current findings through an overview of recently published literature. This overview has focused on the use of agro-industrial waste as a growth substrate for mushroom cultivation and lignocellulolytic enzyme production.

Macrofungi production and economic value have been increasing globally. The demand for macrofungi has expanded rapidly owing to their popularity among consumers, pleasant taste, and unique flavors. The presence of high quality proteins, polysaccharides, unsaturated fatty acids, minerals, triterpene sterols, and secondary metabolites makes macrofungi an important commodity. Macrofungi are well known for their ability to protect from or cure various health problems, such as immunodeficiency, cancer, inflammation, hypertension, hyperlipidemia, hypercholesterolemia, and obesity. Many studies have demonstrated their medicinal properties, supported by both in vivo and in vitro experimental studies, as well as clinical trials. Numerous bioactive compounds isolated from mushrooms, such as polysaccharides, proteins, fats, phenolic compounds, and vitamins, possess strong bioactivities. Consequently, they can be considered as an important source of nutraceuticals. Numerous edible mushrooms have been studied for their bioactivities, but only a few species have made it to the market. Many species remain to be explored. The converging trends and popularity of eastern herbal medicines, natural/organic food product preference, gut-healthy products, and positive outlook towards sports nutrition are supporting the growth in the medicinal mushroom market. The consumption of medicinal mushrooms as functional food or dietary supplement is expected to markedly increase in the future. The global medicinal mushroom market size is projected to increase by USD 13.88 billion from 2018 to 2022. The global market values of promising bioactive compounds, such as lentinan and lovastatin, are also expected to rise. With such a market growth, mushroom nutraceuticals hold to be very promising in the years to come.

The continually expanding use of plastic throughout our world, along with the considerable increase in agricultural productivity, has resulted in a worrying increase in global waste and related environmental problems. The reuse and replacement of plastic with biomaterials, as well as the recycling of agricultural waste, are key components of a strategy to reduce plastic waste. Agricultural waste is characterized as lignocellulosic materials that mainly consist of cellulose, hemicellulose, and lignin. Saprobe fungi are able to convert agricultural waste into nutrients for their own growth and to facilitate the creation of mycelium-based composites (MBC) through bio-fabrication processes. Remarkably, different fungal species, substrates, and pressing and drying methods have resulted in varying chemical, mechanical, physical, and biological properties of the resulting composites that ultimately vary the functional aspects of the finished MBC. Over the last two decades, several innovative designs have produced a variety of MBC that can be applied across a range of industrial uses including in packaging and in the manufacturing of household items, furniture, and building materials that can replace foams, plastics, and wood products. Materials developed from MBC can be considered highly functional materials that offer renewable and biodegradable benefits as promising alternatives. Therefore, a better understanding of the beneficial properties of MBC is crucial for their potential applications in a variety of fields. Here, we have conducted a brief review of the current findings of relevant studies through an overview of recently published literature on MBC production and the physical, mechanical, chemical, and biological properties of these composites for use in innovative architecture, construction, and product designs. The advantages and disadvantages of various applications of mycelium-based materials (MBM) in various fields have been summarized. Finally, patent trends involving the use of MBM as a new and sustainable biomaterial have also been reviewed. The resulting knowledge can be used by researchers to develop and apply MBC in the form of eco-friendly materials in the future.