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Page number:594 
Remarks (internal):F. temperatum and F. subglutinans morphologically were similar in that they both produced conidia on monophialides and polyphialides in false heads on the aerial mycelium. On the other hand F. temperatum can be differentiated from F. subglutinans on the basis of macroconidial characteristics. The macroconidia of F. temperatum are mostly four-septate with a basal cell that is distinctly foot-shaped, whereas those of F. subglutinans were usually three-septate with a relatively poorly developed basal cell (Leslie and Summerell 2006). Nevertheless these differences are not sufficiently robust to consider them key characteristics for routine identification. We chose not to describe formally the teleomorph of F. temperatum, in anticipation of changes in the International Code of Botanical Nomenclature that would remove the requirement for describing both stages. We see no purpose in adding another name for this fungus to the scientific literature (Hawksworth 2009), particularly since the sexual characters associated with F. temperatum do not distinguish it from other species in the GFSC, and perithecia are likely to be observed only when induced in the laboratory.
The interspecies and intraspecies mating compatibility assays of our study also confirmed that F. temperatum represents a new biological species within the American clade of the GFSC. Indeed all F. temperatum were infertile when crossed with the F. circinatum and the F. konzum tester strains. In one replicate MUCL 52463 produced one fertile perithecium with a F. subglutinans tester strain among 150 sterile perithecia. Although one single fertile perithecium cannot be considered a significant indication of interfertility, similar examples between different biological species of the GFSC already have been described (Leslie et al. 2004). Sexual compatibility between the previously described groups 1 and 2 within F. subglutinans was not clear-cut (Steenkamp et al. 2002). The relatively high percentage of female fertile strains and the mating-type ratio observed (MAT1-: MAT1-2 = 17: 13) suggested that sexual reproduction might be common in F. temperatum (Leslie and Klein, 1996), and this inference is supported by the genetic diversity observed in the Belgian F. temperatum strains.
 
Description type:Original description 
Description:Fusarium temperatum J. Scauflaire et F. Munaut, sp. nov. Fig. 3A-K
MycoBank MB518089
Colonies on PDA growing 4-6 (mean = 4.7) mm d-1 at 25 C in the dark, attaining 53-74 (mean = 66) mm diam after 7 d. Aerial mycelium cottony, initially white, becoming pinkish white, rarely tinged violet in the center by the substrate. Pigmentation in reverse slightly pinkish orange. Odor not perceptible. No sclerotia observed. No chlamydospores observed.
Anamorph. - Sporodochia pale orange on PDA, colorless and rare on SNA. Typically macroconidia hyaline, 3-6 septa, mostly 4-septate, falcate, with a beaked curved apical cell and a footlike basal cell, 22-50 (mean = 38) µm long, 2-4 (mean = 3.3) µm wide. Conidiophores of the aerial mycelium erect, branched, terminating in 1-3 phialides. Microconidia produced either singly or in false heads on cylindrical monophialides, intercalary phialides and polyphialides, phialides up to 26 µm long and 4 µm wide. Microconidia abundant, hyaline, 0-2 septa; ellipsoidal to oval, obovoid when unseptate, 3-13 (mean = 8.2) µm long, 2-4 (mean = 2.7) wide; fusiform when 1-2 septa, 11-23 (mean = 17) µm long, 3-5 (mean = 3.9) µm wide. Microconidia not produced in chains.
Teleomorph. - Perithecia ovoid to obpyriform, superficial, mostly aggregated in a small group, seated on a stroma base, and slightly warty; 215-405 (mean = 327) µm high, 170-310 (mean = 238) µm wide; dark purple in 3% KOH, turning red in lactic acid solution. Asci cylindrical, eight-spored, 80-100 (mean = 92) µm long, 6-7 (mean = 6.7) µm wide, apex with a shallow, refractive ring. Ascospores exuded in a cirrhus, smooth, hyaline, ellipsoidal to oval, 1-2 septa, mostly 1-septate (85%), slightly constricted at the septum, 13-22 (mean = 17.5) µm long, 4.5-6 (mean = 5.2) µm wide. Heterothallic species.
Distribution. - South Africa and Belgium. Previously studies indicated that several strains of Fusarium isolated worldwide were conspecific to NRRL 25622, described herein as F. temperatum, that suggests by extension that they also belong to F. temperatum. These strains also were isolated from maize in USA (Mule et al. 2004, Munkvold 2009), in Europe (Moretti et al. 2008), in cool temperate highlands of Guatemala (Torres et al. 2007) and in wet temperate regions of Mexico (Steenkamp et al. 2002).
Isolates examined. - Belgium. Brabant Wallon: Chastre. Isolated from Zea mays, MUCL 52463, MAT1-1 (ex holotype).
 
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