Catenularia angulospora (Linder) E.W. Mason, Mycol. Pap. 5: 121. 1941.

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 angulospora (Linder) E.W. Mason, Mycol. Pap. 5: 121. 1941. Fig. 3

Haplochalara angulospora Basionym. Haplochalara angulospora Linder, Mycologia 25: 347. 1933.

Catenularia hughesii Synonym.? Catenularia hughesii N.D. Sharma, J. Indian bot. Soc. 59: 73. 1980.

Description.

Colonies on natural substrate effuse, hairy to velutinous, dark brown to almost black. Anamorph. Conidiophores 77-220 × 4.5-6(-7) μm wide, 7-8 μm above the base, macronematous, solitary or arise in tufts, erect, straight or slightly flexuous, unbranched, dark brown, paler towards the apex, septate. Capitate hyphae absent. Conidiogenous cells 18-25 × 3.5-4.5 μm tapering to ca. 2.5 μm, integrated, terminal, monophialidic, extending percurrently, obclavate to subcylindrical or slightly lageniform, pale brown, paler towards the apex; collarettes 3-4 μm wide, 1.5(-2) μm deep, funnel-shaped, subhyaline, smooth, margin entire. Conidia 6-8(-9) μm long, 4.5-6(-7) μm wide at the apical end, ca. 2 μm wide at the basal hilum (mean ± SD = 7.4 ± 1.1 × 6.0 ± 1.2 μm × 2.0 ± 0.0 μm), rounded-obconic in side view, with three blunt corners when viewed from above, broadly rounded to flattened at the apex, truncate at the basal scar, pale brown to pale fuscous, thick-walled, smooth; formed singly, adhered in basipetal chains. Teleomorph. Unknown.

Specimen examined.

USA - Kentucky • near Louisville; on decaying beech log; 23 Mar. 1928; D.H. Linder (holotype of C. angulospora FH herbarium 00965375, as microscopic slides).

Habitat and geographical distribution.

Saprobe on dead culms of Bambusa sp., decaying wood of Fagus sp. and other unknown hosts in freshwater and terrestrial habitats. It is known in China, India and the USA ( Linder 1933; Sharma 1980; Luo et al. 2019 as C. cubensis ).

Notes.

For additional description and illustration, see Luo et al. (2019, as C. cubensis ). Hughes (1965) revised the type material of H. angulospora , and despite the striking similarities to other Catenularia , he kept the species in Haplochalara due to the absence of capitate hyphae. Sharma (1980) described C. hughesii on dead bamboo culms in India with pale brown to brown conidia 6-8 × 4.5-5.8 μm and conidiophores up to 270 × 5-7 μm. Although the holotype of this species was not available for study, a detailed morphological comparison of its original description and illustration with C. angulospora suggests that they are conspecific. Luo et al. (2019) reported this species as C. cubensis (strain MFLUCC 18-1331) from China, characterised by the absence of capitate hyphae and cuneiform, greyish-brown to brown conidia 6-8 × 4-6 μm.

In the phylogenetic analysis, the strain of C. angulospora MFLUCC 18-1331 clustered as a sister to C. cubensis S.M.H. 3258, but their relationship is not statistically supported. Both species are, however, very similar. Catenularia cubensis ( Holubová-Jechová 1982) differs from C. angulospora in brown to dark brown conidia, slightly narrower at the apical end (5.5-8.5 × 3.5-5.5 μm), and presence of capitate hyphae scattered among the conidiophores. The ITS sequence identity between C. cubensis and C. angulospora is 96.5% and supports our conclusion to treat them as separate species.

Figures

Figure 3. Catenularia angulospora (holotype FH 00965375) A vertical section of the wood with colony B-D conidiophores with conidia. Scale bars: 500 μm (A); 50 μm (B-D).