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Page number:62 
Remarks (internal):Von Arx (1970) mentioned "pustular, white or reddish" sporodochia when describing the type of Gloeosporium lunatum. These differently pigmented sporodochia may belong to different species, only one of which can be G. lunatum, according to our observations. Reddish sporodochia have a subhymenium of isodiametric cells (fig. 8l) while the subhymenium of the white sporodochia appears to consist of hyphae (not shown). While reddish sporodochia produced 1-septate (fig. 8r, s, u) and less frequently 2-septate conidia (fig. 8t) only aseptate conidia were produced by the white sporodochia. Ellis and Everhart (1891) mentioned "flesh-coloured" fruiting bodies and described the conidia of G. lunatum as 1-septate, 12-20 x 2-3 µm. These characteristics are identical to those of the reddish sporodochia. Accordingly we herewith designate elements of these "flesh-coloured" (Ellis and Everhart 1891) or "reddish" (von Arx 1970) sporodochia (fig. 8l, r-u) as the lectotype of Gloeosporium lunatum. Conidia with one median septum similar to those observed on the reddish sporodochia of the type also are formed by the ex-neotype strain of F. dimerum var. violaceum (CBS 632.76, fig. 8a, b) and Fusarium sp. 5 (CBS 110312; figs. 8c, d). The stromata formed by these strains on carnation leaves are also more reddish than the partly stromatic subhymenia of sporodochia formed by all other species of the FDSG (fig. 3). Accordingly we consider F. dimerum var. violaceum a synonymy of Fusarium (Gloeosporium) lunatum, which agrees with concepts published earlier (von Arx 1970, Sinclair et al 1987). Wolf (1912) however considered G. lunatum to be the anamorph of Sphaerella opuntiae Ellis & Everh. [?Mycosphaerella opuntiae (Ellis & Everh.) Dearness, ?Monographella opuntiae (Ellis & Everh.) von Arx]. Von Arx (1970), Corlett (1991) and Aptroot (2006) accepted this connection, but apparently it was never proven. Aa and Vanev (2002) suggested that Mycosphaerella opuntiae is the teleomorph of Phyllosticta concava Seaver.
The strongly supported reciprocally monophyly of the ex-neotype strain of F. dimerum var. violaceum (F. lunatum) obtained from cultivated plants of the South American "chin cactus" Gymnocalycium damsii and the North American strain from human sinus in Washington state (Fusarium sp. 5) (fig. 2 ) indicate that the morphological species F. lunatum comprises two phylogenetically distinct species. In culture F. lunatum and Fusarium sp. 5 are characterized by predominately 1-septate macroconidia, which on average are longer than those of F. dimerum. They are characterized further by dark violet chlamydospores and sclerotia that are formed abundantly on OA and PDA but are poorly developed on SNA. Fusarium lunatum and Fusarium sp. 5 are the only species of the FDSG that grow poorly on SNA, TA1 and CzA, a finding indicating vitamin or growth factor dependency that in nature is supplied for example by a plant host.
Description type:Non-original description 
Description:Fusarium lunatum (Ellis & Everh.) von Arx, Verh Konink Akad Vetensch Amsterdam 51:101. 1957. FIG. 8a-u.
?Gloeosporium lunatum Ellis & Everh., Proc Acad Nat. Sci Philad: 82. 1891.
?Microdochium lunatum (Ellis & Everh.) von Arx, Trans Br Mycol Soc 83:374. 1984.
= Fusarium dimerum var. violaceum Wollenw., Fus. autogr. delin. 3:854. 1930.
Colonies at 24 C, 7 d on CzA 50-55 mm diam, PDA 40-45, SNA 10-25. Optimum temperature for growth on MEA 27-30 C, colonies 75-85 mm diam after 7 d; maximum temperature 37 C, colonies 5-10 mm (CBS 632.76) or 20 mm (CBS 110312) diam after 7 d. Aerial mycelium on SNA absent, on PDA absent or sparse, rarely moderately developed, white. Colony reverse on PDA brownish yellow, brownish orange (4B5-4B7, 5B8-5C8), on OA typically vinaceous, dark violet or dark carmine (9F8-10F8) either after 14 d or only in older colonies and sometimes only in sectors. Colony surface similar to the reverse.
Sporulation on SNA sparse; on OA, lateral phialidic pegs common, 1.5-4 µm long, 1-1.5 µm wide near aperture. Monophialides formed terminally or laterally on hyphae, 8-38 µm long, 2-3 µm wide at base, 2-4.5 µm at widest point and 1-1.5 µm near aperture; when formed in pionnotal layers or on CL in well developed sporodochia, forming few-membered whorls on short supporting cells, 6-12 µm long, 2.5-3.5 µm wide at base, 3-3.5 µm at widest point and 1-1.5 µm near aperture; polyphialides not seen. Sporodochia formed on carnation leaves consisting of a hymenium of phialides formed on a core of angular to broadly cylindrical, uniformly thin-walled, hyaline cells that emerge from plant material or hemisphaerical to globose sclerotial bodies. Microconidia mostly curved, allantoid to lunate, or less frequently almost straight and ellipsoidal; curved microconidia either almost uniformly rounded at both ends or with a minutely beaked and a slightly pointed distal and proximal end, mostly 0-, rarely 1- or 2-septate, (6.5-) 9-11.5(-17.5) x (1.5-)3-3.5(-4) µm. Macroconidia on young sporodochia frequently 0-septate, (9.5-) 10.5-13(-19) x (2.5-)3-3(-4) µm, on mature sporodochia typically with one median septum, (11.5-) 18-22.5(-26.5) x (2.5-)3-3.5(-4) µm; few 2- and 3-septate conidia seen on specimen NY 00883039 and several week old sporodochia on CL, 21-23.5 x 3 µm. Conidial masses in young pionnotal sporodochia pale to light orange, with age appearing reddish brown due to pigment formed in chlamydospore clusters or stromata; on well developed sporodochia light orange (5A3-5A4) or reddish brown, slimy, accumulated in dome-shaped masses up to 150-300 diam µm (or more). Chlamydospores globose to subglobose, 6-12.5 x 5-9 µm, in long, partly branched chains or aggregated in irregular clusters that can form sclerotial bodies; on SNA mostly in unpigmented chains, on OA and PDA in deep purple or vinaceous clusters, on SNL/CL often accumulating to globose to subglobose, orange to reddish sclerotial bodies 50-100(-200) µm diam.
Type of Gloeosporium lunatum. USA TEXAS: San Antonio. On living leaves of Opuntia sp., Jan 1889, B.F.G. Egeling (NY 00883039!).
Neotype of Fusarium dimerum var. violaceum designated by Gerlach and Nirenberg (1982): Germany. Hessen: Near Frankfurt. From Gymnocalycium damsii (K. Schum.) Britton & Rose in nursery (B, dried culture; ex-type culture CBS 632.76 = NRRL 20690).
Strains studied. - See Table I.
Known distribution. - Clinical strains from USA, Mediterranean countries, nurseries in Germany.
Habitat. - From cacti of genera Opuntia or Gymnocalycium; clinical isolates from human sinus.
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