Persoonia 43, 2019: 90–185 ISSN (Online) 1878-9080 www.ingentaconnect.com/content/nhn/pimj RESEARCH ARTICLE https://doi.org/10.3767/persoonia.2019.43.04 Back to the roots: a reappraisal of Neocosmospora M. Sandoval-Denis1,2, L. Lombard1, P.W. Crous1,2,3 Key words Abstract The genus Neocosmospora (Fusarium solani species complex) contains saprobes, plant endophytes and pathogens of major economic significance as well as opportunistic animal pathogens. Advances in biological Fusarium and phylogenetic species recognition revealed a rich species diversity which has largely remained understudied. new taxa Most of the currently recognised species lack formal descriptions and Latin names, while the taxonomic utility of old systematics names is hampered by the lack of nomenclatural type specimens. Therefore, to stabilise the taxonomy and nomen- taxonomy clature of these important taxa, we examined type specimens and representative cultures of several old names by means of morphology and phylogenetic analyses based on rDNA (ITS and LSU), rpb2 and tef1 sequences. Sixty- eight species are accepted in Neocosmospora, 29 of them described herein as new; while 13 new combinations are made. Eleven additional phylogenetic species are recognized, but remain as yet undescribed. Lectotypes are proposed for eight species, seven species are epitypified and two species are neotypified. Notes on an additional 17 doubtful or excluded taxa are provided. Article info Received: 27 May 2019; Accepted: 16 July 2019; Published: 21 August 2019. INTRODUCTION bean (Ricinus communis), fig (Ficus carica), kaki persimmon (Diospyros kaki), ashleaf maple/ Manitoba maple/ box elder The genus Neocosmospora (Hypocreales, Nectriaceae) in- (Acer negundo), oak (Quercus spp.), oriental plane (Platanus cludes ubiquitous, widely distributed fungi that are commonly orientalis), and the tree of heaven (Ailanthus altissima; Freeman found in soil, plant debris, living plant material, air and water. et al. 2013, O’Donnell et al. 2016), as well as several native Previously assigned to the Fusarium solani species complex host species in South Africa (Paap et al. 2018). (FSSC; O’Donnell 2000) and before that, to sect. Martiella Given their importance as plant pathogens, species of Neocos­ (Wollenweber 1913), this genus encompasses one of the most mospora have been used as model organisms in molecular important groups of plant pathogenic fungi. The included spe- plant pathology (VanEtten et al. 1989, Crowhurst et al. 1992, cies and varieties have been recorded from nearly 500 different O’Donnell 2000 and additional references therein) and for the plant hosts, spanning more than 100 families (Farr & Rossman study of fungal cell biology (Wu et al. 1998, Aist 2002, Coleman cont. updated). Common plant diseases attributed to these taxa 2016). They are also known as producers of bioactive natural include: dry and jelly-end potato rot (Carpenter 1915); head products including antibacterial agents (Bacon et al. 1996, blight of wheat (Triticum aestivum) (Balmas et al. 2015); root rot Merlin et al 2013); cytotoxic compounds like the immunosup- of Citrus spp. (Menge 1988, Polizzi et al. 1992, Sandoval-Denis pressive agents cyclosporine A and C, and naphthoquinones et al. 2018), common bean (Phaseolus vulgaris; Roy 1997), pea (Nakajima et al. 1989, Sugiura et al. 1999, Lee et al. 2014, (Pisum sativum; Porter et al. 2015), peanut (Arachis hypogaea; Takemoto et al. 2014, Rathna et al. 2016, Chowdhury et al. Rojo et al. 2007), sweet potato (Ipomoea batatas; McClure 2017). They are sources of diverse enzymes with industrial 1951) and wheat (Nirenberg 1981); root and fruit rot of cucurbits applications including chitosanases (Liu & Bao 2009), cutinases (Hawthorne et al. 1992), and tomato (Solanum lycopersicum); (Mannesse 1997, Longhi et al. 2005), hydrolases (Jallouli et stem and fruit rot of sweet peppers (Capsicum annuum; Fletcher al. 2015), laccases (Wu & Nian 2014), and lyases (Longhi et 1994, Jarvis et al. 1994), and mango (Mangifera indica); fruit al. 2005); and for the biosynthesis of nanoparticles (Fathima malformation (Liew et al. 2016); stem canker of cottonwood & Balakrishnan 2014). (Populus spp.; Toole 1963), avocado (Persea americana; Guar- naccia et al. 2018), red oak (Quercus rubra; Vujanovic et al. Neocosmospora species have also sporadically been associ- 1999), and walnut (Juglans spp.; Tisserat 1987, Chen & Swart ated with human and animal mycotoxicoses (Ishii et al. 1971, 2000); and sudden death syndrome (SDS) of soybean (Glycine Pitt & Hocking 2009, Antonissen et al. 2014), being producers max; Achenbach et al. 1996, Aoki et al. 2005). Neocosmospora of a wide range of toxins displaying activities against plants and also includes economically important tree-pathogenic mutual- animals, cell cultures and diverse microorganisms. The list of ists of the shot-hole borer beetle (Euwallaceae spp.) originally known toxic metabolites includes furanoterpenoids, ipomeanols associated with dieback of avocado and tea (Camelia sinensis; and ipomeanine (Nelson et al. 1983, 1994, Mawhinney et al. Freeman et al. 2013). This mutualistic association, however, is 2008, Pitt & Hocking 2009), naphthazarins (Achor et al. 1993, now known from various other woody hosts that include castor Van Rensburg et al. 2001), while the alleged production of the trichothecenes scirpentriol, NT-2, T-1, T-2 toxins and neosola- niol are most likely based on misidentified isolates (Ishii et al. 1 Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, 1971, Ueno et al. 1975, Chełkowski 1989). The Netherlands; corresponding author e-mail: [email protected]. Despite their relative rarity compared to infections caused by 2 Faculty of Natural and Agricultural Sciences, Department of Plant Sciences, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa. other fungal pathogens such as Aspergillus and Candida spp., 3 Wageningen University and Research Centre (WUR), Laboratory of Phyto- human and animal infections caused by Neocosmospora spp. pathology, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands. are on the rise (Anaissie et al. 1986, Sutton & Brandt 2011). © 2019 Naturalis Biodiversity Center & Westerdijk Fungal Biodiversity Institute You are free to share - to copy, distribute and transmit the work, under the following conditions: Attribution: You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). Non-commercial: You may not use this work for commercial purposes. No derivative works: You may not alter, transform, or build upon this work. For any reuse or distribution, you must make clear to others the license terms of this work, which can be found at http://creativecommons.org/licenses/by-nc-nd/3.0/legalcode. Any of the above conditions can be waived if you get permission from the copyright holder. Nothing in this license impairs or restricts the author’s moral rights. M. Sandoval-Denis et al.: A reappraisal of Neocosmospora 91 This increase is driven by a multitude of causes, mostly related (Nelson et al. 1983, Leslie & Summerell 2006). Nevertheless, to the increased incidence of specific host predisposing factors several authors rejected Snyder & Hansen’s system in favour of and immunocompromising conditions that include corticosteroid narrower species circumscriptions. Raillo (1950) acknowledged therapy, grafts, haematological malignancies, HIV infection, four species, F. caeruleum, F. javanicum, F. martii and F. solani, prolonged neutropenia, prosthetic devices and transplantations. plus numerous morphological varieties and formae, and also Additionally, the development of new diagnostic tools and the added new combinations including eight new formae and two currently improved awareness of medical personnel on the subspecies. Bilai (1955) emended sect. Martiella to include taxa importance of fungal infections have greatly increased accurate from sections Eupionnotes and Ventricosum, though she recog- identification of the causal agent (Guarro 2013, Slavin et al. nised only three species: F. javanicum, F. merismoides and 2015). Although nearly 50 % of fusarial infections have been F. solani. Fusarium caeruleum was reduced to being a variety attributed to the traditional concept of N. solani, recent phyloge- of F. solani. Booth (1971) partially followed both Wollen weber netic studies have shown that infections due to Neocosmospora & Reinking and Snyder & Hansen’s systems, and combined spp. are not limited to N. solani s.str. (O’Donnell et al. 2008, sections Martiella and Ventricosum. He accepted four species, Guarro 2013, Sandoval-Denis & Crous 2018). Other Neocosmo­ including F. illudens, F. solani with 18 ff. spp., F. tumidum and spora spp. that include N. petroliphila, N. falciformis, and in par- F. ventricosum. He agreed with Bilai on the varietal status of ticular N. keratoplastica are now also known to be more fre- F. caeruleum. Similarly, Joffe & Palti (1972) and Joffe (1974) quently associated with cutaneous, subcutaneous or deep accepted only two species: F. solani with its varieties caeruleum seated, commonly devastating infections of highly immuno- and ventricosum, and F. javanicum. More recently, Gerlach & compromised patients (Guarro 2013, Short et al. 2013). Nirenberg (1982) accepted six species, F. caeruleum, F. cauca­ sicum, F. eumartii, F. illudens, F. javanicum with two varieties Species concepts in Neocosmospora, and F. solani with four varieties.