Codinaea paniculata Reblova & J. Fourn., 2020

Reblova, Martina, Nekvindova, Jana, Fournier, Jacques & Miller, Andrew N., 2020, Delimitation, new species and teleomorph-anamorph relationships in Codinaea, Dendrophoma, Paragaeumannomyces and Striatosphaeria (Chaetosphaeriaceae), MycoKeys 74, pp. 17-74 : 17

Codinaea paniculata Reblova & J. Fourn. sp. nov. Figure 3

Typification.

France - Ariège • Pyrénées Mts., Rimont, La Maille brook; alt. 550 m; 28 May 2018 (incubated in moist chamber for 1 wk); on submerged decaying wood; J. Fournier leg.; M.R. 3950 (holotype: PRA-16319!, ex-type culture CBS 145098).

Etymology.

Panicula (Latin) tuft, referring to the dense groups of setae and conidiophores on the natural substrate.

Description on the natural substrate.

Colonies on the nature substrate effuse, hairy, greyish-brown. Setae erect, straight or slightly flexuous, smooth-walled, dark brown and thick-walled, becoming pale brown to subhyaline and thin-walled towards the apex, 230-290 μm long, 6-7.5 μm wide above the base, tapering gradually towards the apex which almost always develops into a monophialide. Conidiophores macronematous, mononematous, 62-127 × 3.5-4.5 µm, septate, erect, straight or flexuous, arising singly or in groups of 4-6 from hyphal cells associated with the bases of setae, septate, mid-brown to pale brown becoming gradually paler towards the apex. Conidiogenous cells 16.5-30(-38) × 3.5-5 μm, tapering to 1.5-2 μm just below the collarette, integrated, terminal, monophialidic, cylindrical to cylindrical-lageniform, subhyaline or pale brown at the base becoming hyaline to subhyaline towards the apex, smooth-walled; collarettes funnel-shaped, 3.5-4.5 μm wide, 1.5-2.5 μm deep. Conidia in slimy droplets, hyaline in mass, (11.5-)12-17 × (2-)2.5-3(-3.5) µm (mean ± SD = 14.7 ± 1.5 × 2.5 ± 0.3 µm), of two types, narrower and longer, 13.5-17(-17.5) × 2.5-3.5 μm (mean ± SD = 15.2 ± 1.0 × 2.8 ± 0.3 µm), and shorter and usually wider, 11.5-13.5(-14) × 3-3.5(-4) μm, falcate, asymmetrical, rounded at the apical end, with an inconspicuous scar at the basal end, hyaline, aseptate, smooth-walled, with simple, straight or gently curved setulae at both ends, 5-8 μm long; setulae inserted on the concave sides of the conidia.

Description on MLA.

Vegetative hyphae hyaline to pale brown. Setae absent. Conidiophores 95-150(-195) μm long, 3.5-4.5 μm wide, conidiogenous cells 25-35 × 3.5-4(-4.5) μm, tapering to 1.5 µm just below the collarette, integrated, terminal, polyphialidic, usually cylindrical, pale brown to subhyaline, smooth-walled; collarette funnel-shaped, 3.5-4(-4.5) μm wide, 1.5-2 μm deep. Conidia in slimy droplets, of two types, narrower and longer (13-)13.5-15.5(-17) × 2.5-3 µm (mean ± SD = 14.4 ± 0.9 × 2.7 ± 0.2 µm), usually slightly wider and shorter 11-13 × 2.5-3.5 µm (mean ± SD = 12.0 ± 0.7 × 3.1 ± 0.3 µm), falcate, asymmetrical, hyaline, with simple setulae 3.5-5.5(-7.5) μm long at both ends.

Culture characteristics.

On CMD colonies 80-85 mm diam, circular, flat, margin fimbriate, aerial mycelium restricted mainly to the centre and margin of the colony, sparsely lanose, floccose centrally becoming mucoid towards the margin, cobwebby at the margin, colony centre whitish, pale brown to creamy towards the margin, pale brown pigment diffusing from the centre of the colony to the agar; reverse creamy. On MLA colonies 65-70 mm diam, circular, slightly raised, margin filiform, lanose, floccose, colony centre whitish becoming brown-grey towards the margin with a brown outer zone of submerged growth, pale brown pigment diffusing to the agar; reverse dark brown. On OA colonies 89-95 mm diam, circular, raised, margin filiform, aerial mycelium occasionally reduced or absent, colonies similar to those on MLA, lanose, floccose, locally mucoid and smooth or cobwebby, whitish becoming dark grey at the margin, a dark brown to burgundy brown pigment diffusing to the agar; reverse dark grey. On PCA colonies 78-89 mm diam, circular, flat to slightly raised, margin entire to weakly filiform, lanose, floccose, occasionally locally mucoid and smooth or with sparse decumbent aerial hyphae, cobwebby at the margin, whitish becoming brown towards the margin; reverse olivaceous brown. Sporulation on MLA, OA, CMD after 8 wk.

Other specimen examined.

France - Ariège • Pyrénées Mts., Rimont, Le Baup stream, ca. 1.5 km from the village along D18 road; alt. 550 m; 12 Jun. 2009; on submerged wood of Fraxinus excelsior ; J. Fournier leg.; J.F. 09153 (PRA-16320, culture CBS 127692) • Ibid.; 23 May 2008; on submerged wood of Alnus glutinosa ; J. Fournier & M. Delpont leg.; J.F. 08124 (PRA-16321, culture CBS 126573). United Kingdom • Liverpool, University Campus Liverpool; 1992; on submerged dead leaf in a pool; G.L. Hennebert leg.; (culture MUCL 34876).

Habitat and distribution.

All four isolates analysed in this study originated from the freshwater environment and occurred on decaying wood or leaves of Alnus glutinosa , Fraxinus excelsior and other unidentified hosts. Based on the BLASTn search of the ITS sequence of C. paniculata in GenBank, two isolates from roots of Elymus mollis (ITS: KU838460, KU839605, David et al. 2016), a native beach grass on the USA Pacific Northwest coast, and one environmental soil sample from ancient woodland enclosing a conifer plantation in the United Kingdom (ITS: KM374380, Johnson et al. 2014) showed 100 % sequence similarity. Based on these records, C. paniculata is known from the north temperate region in Europe in France and United Kingdom and North America in USA, Oregon.

Notes.

Among known Codinaea species, C. assamica is similar to C. paniculata , but differs by slightly longer (14.6-16.8 × 2.6-2.8 µm) conidia with longer (9.6-12.8 µm) setulae ( Hughes and Kendrick 1968) and formation of polyphialides in vivo. Dictyochaeta terminalis ( Lin et al. 2019) matches C. paniculata in monophialidic conidiogenous cells formed in vivo and aseptate conidia, which are slightly longer and wider (14.7-20.7 × 2.9-4.2 µm). The ITS sequences of examined strains of C. paniculata exhibit 99.94-100 % similarity; their comparison with ITS sequences of the closely related C. assamica CBS 242.66 (MH858788) and D. terminalis GZCC 18-0085 (MN104613) showed 89.7 % and 89.85 % similarity, respectively.

Figures

Figure 3. Codinaea paniculata. A-C setae and conidiophores on nature substrate D-G conidia on nature substrate H-L conidiophores in MLA culture (6 wk) M-O conidia in MLA culture (6 wk) P colonies on CMD, MLA, OA and PCA after 4 wk (from left to right). Images: CBS 145098 (A, B, G-O); CBS 126573 (C); CBS 127692 (D-F). Scale bars: 20 μm (A-C); 10 μm (D-O); 1 cm (P).