Notes: Fusarium agreste, previously recognized as lineage Fusarium sp. nov. 8 in Laraba et al. (2021), resolved as the closest phylogenetic sibling of F. sambucinum, clustering in an intermediate position between F. sambucinum and F. symmetricum, the three species producing relatively fast growing, red colonies on PDA and up to 5-septate sporodochial conidia of similar width. Nevertheless, phylogenetic analyses, coupled with multilocus and most singlelocus coalescent-based analyses support the recognition of this clade as a genetically exclusive novel taxon, which is reinforced by morphological features. Fusarium agreste can be distinguished from F. sambucinum and F. symmetricum by its longer and robust conidia with well-developed foot-cells and by the production of 0–1-septate microconidia on aerial conidiophores. Both F. agreste and F. symmetricum are so far known to occur in the Southern Hemisphere; F. agreste in South Africa and New Zealand, while the latter species is known from Cactaceae in South America. In contrast, F. sambucinum has a worldwide distribution and has been recorded from more than 150 different substrates, including soil, animals (among them insects, and mammals, including human), and more than 130 plant host; mostly from Fabaceae, Poaceae, Pinaceae and Solanaceae (Farr et al. 2023).

Notes: Previously assigned to lineage Fusarium sp. nov. 12 (Laraba et al. 2021), F. amblysporum is here described from a set of strains previously stored in culture collections as either F. compactum, F. sambucinum or F. venenatum. Fusarium compactum, a member of the Fusarium incarnatum-equiseti SC produces similar PDA colonies to F. amblysporum, and all three species mentioned above produce wide (averaging > 5.4 µm wide) sporodochial conidia. Conidia of F. amblysporum, F. sambucinum and F. venenatum, however, all differ from those of F. compactum by being more uniform in shape, robust, with a less evident tapering. Fusarium amblysporum can be distinguished from its FSAMSC counterparts above, by its slightly faster growth rate and pigmentation on PDA, which can vary substantially from white to rosy buff, but not reaching the intense red colour observed in F. sambucinum and F. venenatum

Notes: For comments about the F. graminearum s. lat. clade see notes under F. acaciae-mearnsii and F. graminearum. Although resolved by phylogenetic and STACEY analyses, F. cortaderiae is morphologically indistinguishable from its closest phylogenetic sibling F. brasilicum, both species forming asymmetric, straight to curved, 4.5–5 µm wide, 5-septate conidia, with narrow apical beaks, and wider below the median (Aoki et al. 2012). Moreover, both species overlap in their host preferences and partially in their biogeographic patterns; however, F. cortaderiae has a wider geographical distribution, with additional records in Europe (Italy), Oceania (Australia and New Zealand) and South America (Argentina, Brazil, and Uruguay), apart from Africa (South Africa) (Farr et al. 2023). In addition, unlike F. brasilicum, known only from a restricted number of Poaceae hosts (Avena sativa, Hordeum vulgare, and Triticum sp.), F. cortaderiae is known from Asteraceae (Gerbera sp.), Caryophyllaceae (Dianthus sp.), Fabaceae (Glycine max), Poaceae (Cortaderia selloana, Hordeum vulgare, Lolium multiflorum, Oryza sativa, Triticum aestivum, Triticum durum, and Zea mays), and soil (Farr et al. 2023)

Notes: For comments about the F. graminearum s. lat. clade see notes under F. acaciae-mearnsii and F. graminearum. In comparison to other F. graminearum s. lat. segregates, F. gerlachii has a reduced host and geographical range, being known from Poaceae (Arundo donax, Dactylis glomerata, and Triticum aestivum) in the USA and New Zealand (Aoki et al. 2012, Farr et al. 2023). It is morphologically distinguished by producing 4.5–5 µm wide, gradually curved, asymmetric 5-septate macroconidia, with beaked apical cells (Aoki et al. 2012)

Notes: Fusarium mastigosporum is one of nine segregates of F. longipes recognized here (see additional notes under F. cygneum and F. longipes). Previously assigned to Fusarium longipes 1 in Laraba et al. (2021), it produces large whip-like macroconidia, common, but not exclusive to the Longipes clade of FSAMSC, and observed also in F. cygneum, F. dolichosporum, F. longicolle, F. magnum, and F. procumbens. Fusarium mastigosporum is distinguished by a combination of characters i.e., very long (av. 127.7 × 4.3 µm), robust, whip-like sporodochial conidia, and the presence of a secondary, falcate macroconidial morphotype on aerial conidiophores.
This species has been recorded on soil, other fungi (Daldinia sp.), and plant hosts in Poaceae (Sporobolus africanus and Triticim sp.), Rosaceae (Rubus sp.), and Solanaceae (Solanum tuberosum), in North America (US), Europe (Germany), and Oceania (Australia and New Zealand) (Farr et al. 2023)

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Notes: A rare species known from New Zealand, F. praegraminearum was shown to induce moderate head blight symptoms on wheat under in vitro conditions (Gräfenhan et al. 2016). Morphologically, F. praegraminearum has been compared to F. dactylidis, F. graminearum, F. pseudograminearum (all three in the Graminearum clade) and F. acuminatum (FTSC), being distinguished by a combination of colony characteristics and its conidial shape. For a detailed morphological comparison see Gräfenhan et al. (2016)

Notes: Fusarium pseudograminearum, formerly known as F. graminearum Group 1 was the first segregate population of F. graminearum s. lat. to be formally described as a different taxon (see additional comments under F. graminearum) (Aoki & O’Donnell 1999a, b). Phylogenetically, it resolves as the nearest relative to F. dactylidis, from which it differs by producing chlamydospores and larger multiseptate conidia.Fusarium pseudograminearum is a soil-borne fungus and causes Fusarium crown rot and occasionally Fusarium head blight on small grain cereals, and has been recently evaluated as a potential quarantine pest in the EU (EFSA Panel on Plant Health et al. 2022). Although the outcome of the pest categorization indicated that it is a potential Union quarantine pest, it has not been included in the EU Commission Implementing Regulation 2019/2072 yet. It is known to affect several hosts in Fabaceae (Glycine max, and Medicago spp.), Poaceae (Aegilops tauschii, Ammophila sp., Austrostipa aristiglumis, Avena sp., Dactylis glomerata, Hordeum spp., Lolium sp., Panicum virgatum, Triticum spp., and Zea mays), and Rosaceae (Malus domestica); and experimentally proven to also infect Brassicaceae (Brassica napus), Fabaceae (Cicer arietinum), Poaceae (Oryza sativa, Secale cereale, Sorghum sp., and Triticosecale rimpaui) (Akinsanmi et al. 2007, EFSA Panel on Plant Health et al. 2022, Farr et al. 2023). This is a globally distributed species reported from Asia (Azerbaijan, China, Iran, Malaysia, Syria, Iraq, and Türkiye), Africa (Algeria, Morocco, South Africa, and Tunisia), Europe (Italy, Netherlands, and Spain), North and South America (Argentina, Canada and USA), and Oceania (Australia, New Zealand) (EFSA Panel on Plant Health et al. 2022, Farr et al. 2023).

Notes: The original description of Fusarium by Link (1809), with a single species, F. roseum, was based on elements of different fungi i.e., F. avenaceum, F. sambucinum and F. sporotrichioides, in their current concepts (Wollenweber 1916, Gams et al. 1997). The generic name was later sanctioned by Fries (1832), citing only a malvaceous host, hence determining the application of the name (Domsch et al. 2006). The posterior inaccurate use of the name F. roseum by Snyder & Hansen (1945) for an assemblage of over 20 different taxa which excluded the original concept of F. roseum, rendered the latter name ambiguous and unapplicable (Gams et al. 1997). Thus, a proposal to conserve the name F. sambucinum over F. roseum and earlier synonyms was adopted (Gams et al. 1997, Gams 1999). The lectotype of F. sambucinum is shown in Fig. 64. An earlier, often neglected homonym, F. sambucinum Brondeau (Brondeau 1855) is unavailable because of the conserved status of F. sambucinum Fuckel. The latter name is conserved against all names listed as rejected, and against all combinations of the rejected names (Art. 14.4), as well as against all earlier homonyms (Art 14.10). The current taxonomic position of F. sambucinum Brondeau is unknown; however, with “short, obtuse sporidia” it probably corresponds to a species different than the present concept of F. sambucinum.
Several specimens of F. sambucinum were recently collected from its original host (Sambucus nigra) in Germany, from which seven monosporic cultures, isolated from either ascospores or sporodochial conidia were included here. Their identity was confirmed by morphological and phylogenetic analyses, and sexual crosses with a known F. sambucinum (G. pulicaris) tester strain. To fix the application of the name F. sambucinum to a defined phylogenetic clade, an epitype was selected here (CBS H-25241), and an ex-epitype culture (CBS 151942) was made available to facilitate further research (Fig. 65). The phylogenetic analysis presented in He et al. (2024) indicates CBS 146.95 as “ex-holotype” of F. sambucinum, which is incorrect in every aspect (wrong collection year, collector, country, and substrate).
Fusarium sambucinum resides in the Sambucinum clade of FSAMSC, being morphologically and phylogenetically close to F. agreste, F. seculiforme and F. symmetricum. Shorter macroconidia (av. 28 µm long) differentiate F. sambucinum from F. agreste (av. 34.6 µm long) and differs from F. seculiforme and F. symmetricum by having distinctly apically curved (asymmetrical) conidia, often with a pointy apex, and wider above the median. Additional species commonly compared with F. sambucinum are F. torulosum and F. venenatum (Nirenberg 1995, Leslie & Summerell 2006, Domsch et al. 2007). Fusarium torulosum is genetically unrelated, allocated in the FTSC, and differs by its slow growing colonies, narrower macroconidia, and long chains of chlamydospores (Nirenberg 1995, Leslie & Summerell 2006), while F. venenatum commonly presents slightly larger conidia (av. 44.5 µm long vs 30 µm in F. sambucinum) with up to 9 septa (up to 5 septa in F. sambucinum), and characteristic chlamydospores arranged in curved, terminal chains (Nirenberg 1995, Leslie & Summerell 2006).
Reports of F. sambucinum exist from all over the world, from more than 60 countries in all continents, except Antarctica. This species has been isolated from soil, insects, mammals and human specimens; and it is associated with over 130 plant hosts, either as an endophyte, saprophyte, or inducing canker, die-back or rot symptoms (fruit and root rot, potato dry rot, and storage rot) in more than 100 genera in 45 different families (Farr et al. 2023). However, reports and diseases attributed to F. sambucinum before 1995 should be verified since they could include isolates now identifiable as F. torulosum or F. venenatum (Leslie & Summerell 2006)

Notes: Fusarium sporotrichioides was recently lectotypified by Crous et al. (2021), the lectotype, an original drawing by C.D. Sherbakoff is reproduced here (Fig. 68). Epitypification, however, is still pending the selection of a suitable specimen from the correct host and country.Fusarium sporotrichioides produces pyriform microconidia, which can be confused with the napiform to globose microconidia of its closest molecular and morphological sibling species F. langsethiae and F. sibiricum; and, with the globose to pyriform microconidia of the distantly related F. poae (Sambucinum clade). The presence of polyphialides distinguishes F. sporotrichioides from F. poae. This same feature and its red PDA colonies distinguishes F. sporotrichioides from F. sibiricum. Lastly, the presence of either aerial or sporodochial macroconidia and mesoconidia separates F. sporotrichioides from F. langsethiae. Unlike morphologically similar species (F. langsethiae, F. poae, and F. sibiricum), F. sporotrichioides is common in soil, in temperate and tropical climates (Leslie & Summerell 2006, Domsch et al. 2007). It has also been reported from animal feed, insects, as a human pathogen, and from mushrooms, and it is a potent mycotoxin (trichothecenes) producer (O’Donnell et al. 2012, Al-Hatmi 2016, Farr et al. 2023). Known plant hosts include over 70 genera, mostly in Poaceae, but also Sapindaceae, Apiaceae, Aquifoliaceae, Araliaceae, Arecaceae, Asteraceae, Betulaceae, Cactaceae, Cannabaceae, Caryophyllaceae, Cucurbitaceae, Ericaceae, Fabaceae, Iridaceae, Juncaceae, Lamiaceae, Linaceae, Lythraceae, Malvaceae, Musaceae, Nymphalidae, Pinaceae, Rosaceae, Rutaceae, Salicaceae, Sclerotiniaceae, Solanaceae, Tortricidae, Typhaceae, and Verbenaceae (Farr et al. 2023); described from Africa (Nigeria, South Africa, and Tanzania), Asia (Bahrain, China, Iran, Japan, Malaysia, Oman, and Türkiye), Europe (Austria, Belgium, Bulgaria, Croatia, Denmark, England, Finland, France, Germany, Hungary, Italy, Norway, Poland, Russia, UK, and the former Yugoslavia), North and South America (Barbados, Brazil, Canada, Chile, Colombia, Mexico, Puerto Rico, and the USA); and Oceania (Australia, and New Zealand). However, due to inaccurate morphological determinations in published literature, host and geographic records need to be reassessed (Domsch et al. 2007)

Notes: Fusarium venenatum was described as a segregate species from F. sambucinum, together with F. torulosum, the three species originally distinguished by their macroconidial size, presence of microconidia and chlamydospores, and growth rates on PDA (Nirenberg 1995). Fusarium torulosum, differing by slower growth rates, red/purple PDA pigmentation, and narrower macroconidia (Nirenberg 1995, Leslie & Summerell 2006, Domsch et al. 2007) was later reaccommodated in the FTSC, hence it is genetically distant to F. sambucinum and F. venenatum (O’Donnell et al. 2013, Crous et al. 2021, Laraba et al. 2022). Both Fusarium sambucinum and F. venenatum are nested within the Sambucinum clade of FSAMSC but are well-resolved phylogenetically. With up to 9-septate macroconidia averaging 44.5 µm long, its typical terminal chains of chlamydospores, and lacking microconidia, F. venenatum differs from F. sambucinum (macroconidia av. 30 µm long, up to 5-septate) and the closest phylogenetic siblings F. amblysporum (macroconidia av. 47.4 µm long, up to 7-septate) and F. cultriforme (macroconidia av. 30.2 µm long, up to 5-septate). Additionally, the growth rates and pigmentation of F. venenatum on PDA (intense red colonies, av. 7.6 mm/d) differ from those of F. amblysporum (white to rosy buff, av. 8.2 mm/d), and F. cultriforme (yellow, av. 4.3 mm/d).
Fusarium venenatum is known from soil, soil debris, and several plant hosts in Amaranthaceae (Beta vulgaris), Asteraceae (Tanacetum cinerariifolium), Cannabaceae (Humulus spp.), and Poaceae (Hordeum vulgare, Triticum spp., and Zea mays), mostly from Europe (Austria, England, Finland, France, Germany, Norway, Poland, Russia, and Spain), but also in Oceania (Australia, New Zealand, Tasmania) and the USA (Farr et al. 2023). The strains involved in the production of the commercial mycoprotein Quorn, originally assigned to F. graminearum, were later identified as F. venenatum by O’Donnell et al. (1998a).