Catenularia novae-zelandiae (S. Hughes & Shoemaker) Reblova & A.N. Mill., 2021

Reblova, Martina, Nekvindova, Jana & Miller, Andrew N., 2021, Phylogeny and taxonomy of Catenularia and similar fungi with catenate conidia, MycoKeys 81, pp. 1-44 : 1

Catenularia novae-zelandiae (S. Hughes & Shoemaker) Reblova & A.N. Mill. comb. nov. Fig. 7

Chaetosphaeria novae-zelandiae Basionym. Chaetosphaeria novae-zelandiae S. Hughes & Shoemaker, N. Z. J. Bot. 3: 138. 1965.

Description.

Colonies on natural substrate effuse, tufted or velutinous, dark brown, mycelium partly immersed, partly superficial, brown; colonies composed of conidiophores, capitate hyphae and sometimes ascomata. Anamorph. Conidiophores 90-354 × 7.5-9.5 μm, 7-10.5 μm wide near the swollen base, macronematous, solitary or arise in tufts, with dark stromatic hyphal cells around the base, erect, straight or flexuous, unbranched, brown to dark brown, thick-walled. Capitate hyphae 95-215 × 5-7 μm, 6.5-9 μm wide above the base, 4.5-5.5 μm wide at the apex, solitary or in tufts, arise among the conidiophores, erect, straight to slightly flexuous, dark brown, paler towards the apex, apical cell pale brown to subhyaline, slightly swollen, broadly rounded, thin-walled, with a hyaline, mucilaginous cap that disintegrates with age. Conidiogenous cells 22.5-41(-65) × 7-11 μm, 7.5-9.5 μm wide below the collarette, terminal, integrated, monophialidic, extending percurrently, cylindrical, subcylindrical or slightly lageniform, brown, producing conidia successively; collarettes 19-27 μm wide and 12.2-19 μm deep, funnel-shaped or cup-shaped, brown to dark brown, roughened, with a frayed margin, the margin deteriorates, and the collarette becomes reduced in size 11.5-15.8 μm wide and 4.5-6 μm deep. Conidia 11.5-17.5 μm long, 14.5-18.5 μm wide at the apical end, 4-5.5 μm wide at the basal hilum, (mean ± SD = 15.8 ± 1.8 × 15.9 ± 1.3 × 5.5 ± 0.9 μm), cuneiform to rounded-obconic in side view, with 4-5 blunt corners when viewed from above, flattened to broadly rounded at the apex, truncate at the base, aseptate, brown to dark brown, thick-walled, smooth; formed singly, adhered in basipetal chains. Teleomorph. Ascomata 160-210 μm diam, 180-220 μm high, superficial, solitary or in small groups, subglobose to globose, papillate, dark brown, sometimes covered with capitate hyphae and conidiophores; capitate hyphae 80-130 × 5-5.5 μm, erect, simple, apical cell 6-6.5 μm wide, slightly inflated, broadly rounded apically, subhyaline, with a mucilaginous cap that disappears with age. Ostiole periphysate. Ascomatal wall fragile, carbonaceous, 17-22 μm thick, two-layered. Outer layer consisting of dark brown, polyhedral to angular cells with opaque walls. Inner layer consisting of rows of thin-walled, hyaline cells. Paraphyses 4-5 μm wide tapering to 1.5-2 μm, septate, hyaline, longer than the asci. Asci 102-130 × 11-13 μm (mean ± SD = 117.6 ± 9.8 × 12.3 ± 0.8 µm), 74-100(-110) μm in the sporiferous part (mean ± SD = 83.7 ± 12 µm), cylindrical-clavate, narrowly truncate apically, ascal apex with a non-amyloid apical annulus 3.5-4 μm wide, ca. 2 μm high. Ascospores 22-28(-30) × 4-5 μm (mean ± SD = 25.6 ± 1.6 × 4.7 ± 0.4 µm), fusiform, straight or slightly curved, hyaline, 3-septate, smooth, 2-seriate in the ascus.

Characteristics in culture.

On PCA: colonies 8-12 mm in 14d, circular, flat, margin entire, subsurface, aerial mycelium scarce, cobwebby to mucoid, beige-brown, reverse of the same colour. Sporulation was abundant, sporulating conidiophores developed from aerial mycelium and occasionally from immersed vegetative hyphae.

Colonies on PCA effuse, hairy, vegetative mycelium subhyaline to hyaline, 2-3 μm wide. Conidiophores, conidiogenous cells and conidia similar to those from nature. Conidiophores 31-120 × 6-7 μm, solitary or arise in tufts of 2-7, erect, straight, pale brown, 1-several-septate. Capitate hyphae absent. Conidiogenous cells 22-37 × 8-10 μm, tapering to ca. 7 μm below the collarette; collarettes 12.5-15 μm wide, 4-6(-8) μm deep, funnel-shaped, pale brown to dark brown, slightly roughened with a frayed to entire margin. Conidia (13-)14-18 μm long, 13-18 μm wide at the apical end, 4.5-6 μm wide basal hilum (mean ± SD = 15.2 ± 1.2 × 14.7 ± 1.4 µm × 5.5 ± 0.9 µm), broadly rounded-obconic in side view, aseptate, brown to grey-brown, thick-walled, smooth, formed singly, adhered in short basipetal chains.

Specimens examined.

New Zealand - Auckland region • Auckland district, Upper Piha Valley, Waitākere Ranges, Home track; on decaying wood of Metrosideros robusta ; 9 Oct. 1963; J.M. Dingley (holotype PDD 21603 , isotype DAOM 93575) . New Zealand - West Coast region • Westland district, Otira, Kelly Shelter , Cockayane Nature Walk ; on decaying wood; 16 Mar. 2003; M. Réblová MR 2846 / NZ 362 ( PDD 81883 ) . New Zealand - West Coast region • Buller district, Victoria Forest Park, Reefton , Big River Inanganua track ca. 14 km; on decaying wood of Nothofagus sp.; 6 Mar. 2003; M. Réblová MR 2723 / NZ 224A (PDD 119362).

Habitat and geographical distribution.

Saprobe on decaying wood of Coprosma lucida , Coprosma spp., Freycinetia banksii , Griselinia lucida , Leptospermum ericoides , Metrosideros robusta , Neopanax arboreum , Nothofagus sp., Olearia rani , Weinmannia racemosa and other unknown hosts, known only in New Zealand ( Hughes 1965; this study).

Notes.

The specimen PDD 81883 of C. novae-zelandiae was isolated in axenic culture (Fig. 7O-Q ). In vitro, conidia were paler than those from nature and broadly rounded-obconic. Unfortunately, the isolate is no longer viable. The other collection PDD 119362 has conidia slightly larger 17.5-21 × 18-19 μm, 5-6 μm wide at the truncate base. In both specimens, we observed several conidia with minute hyaline appendages arising from the pale, circular, thin-walled areas in the cell wall (Fig. 7K ).

Catenularia malabarica ( Subramanian and Bhat 1989) is similar to C. novae-zelandiae in characters of conidia, but differs in the absence of capitate hyphae, longer conidiophores up to 620 μm long and conidiogenous cells with a shallow, funnel-shaped collarette without a frayed margin.

Figures

Figure 7. Catenularia novae-zelandiae A ascomata B colony composed of conidiophores and capitate hyphae C, D, O, P conidiophores E capitate hypha arising among conidiophores F-I upper parts of conidiophores with conidia (arrow indicates central pore at the basal scar) J, K conidia in chain (arrow indicates appendages) L, M asci with ascospores and paraphyses N capitate hypha arising from the ascomal wall Q conidia. Images: PDD 81883 (A-C, F-I, L-Q); PDD 119362 (D, E, J, K); on natural substrate (A-N); in PCA culture after 2 wk (O-Q). Scale bars: 250 μm (A, B); 50 μm (C-E); 20 μm (F-Q).