Claviradulomyces tabebuiae L.L.Duarte, D.M.Macedo & R.W.Barreto, 2021

Duarte, Lidiane Leal, M, Davi, Macedo, esquita de & Barreto, Robert Weingart, 2021, Cryptic but ubiquitous: Claviradulomyceae fam. nov. with five novel species of the lenticel fungus Claviradulomyces from Brazil, Cryptogamie, Mycologie 20 (7), pp. 121-135 : 130-131

Claviradulomyces tabebuiae L.L.Duarte, D.M.Macedo & R.W.Barreto , sp. nov.

( Fig. 5 )

MYCOBANK NUMBER. — MB 811920.

HOLOTYPE. — Brazil. Minas Gerais, Viçosa, Fazenda Antuérpia Mineira, on branches of Tabebuia roseo-alba (Ridl.) Sandwith ( Bignoniaceae ), 18. XII..2013, R. W.Barreto ( VIC 42848; ex-type culture COAD 1935; GenBank LSU sequence KP975454, rpb 2 sequence MW 191754).

ETYMOLOGY. — Referring to its host-genus Tabebuia .

DIAGNOSIS. — Differs from other known species of Claviradulomyces by forming larger pycnidia (70-230 Μm diam) and very long (up to 540 Μm) rostra.

HABITAT AND DISTRIBUTION. — Inside lenticels on branches of ornamental tree Tabebuia roseo-alba at a commercial nursery.

DESCRIPTION

Asexual morph mostly in abnormal hypertrophied spongy lenticels of defoliated living branches. Conidiomata pycnidial, semi-immersed, subglobose to globose, isolated, 70-230 Μm diam, walls subhyaline to olivaceous, textura intrincata at base, changing into pale brown textura angularis in upper half, smooth, ostiolate, rostrate; neck long sinuous, vermiform, 160-540 × 37 Μm, medium to dark brown becoming light brown at the tip, textura porrecta. Conidiophores reduced to conidiogenous cells, holoblastic, suboblate to somewhat lageniform, straight to slightly curved, 3.5-5 × 1.5-2 Μm, hyaline, smooth. Conidia fusoid-filiform to narrowly acerose, 32-40 × 2-2.5 Μm, straight to slightly curved, attenuated toward the acute tip, subtly heeled at the base ending in very short narrow stalk, aseptate, guttulate, subhyaline to hyaline, smooth. Sexual morph not observed.

Culture characteristics

Very slow growing (1.5-2 cm diam after 40 days), colonies dry, flat to slightly depressed, with lobed or entire margins, aerial mycelium scarce and immersed at periphery; either buff centrally, followed by an isabelline band or evenly buff or honey, darkening the culture medium around the colony; not sporulating.

NOTES

Claviradulomyces tabebuiae sp. nov., produces large pycnidia which bear long vermiform rostra, 160-540 Μm, (the longest amongst the known members of the genus). Additionally, it produces the smallest conidiophores, 3.5-5 × 1.5-2 Μm known for the genus.

Figures

FIG. 5. — Claviradulomyces tabebuiae sp. nov. (VIC 42848,holotype): A, Tabebuia roseo-alba (Ridl.) Sandwith stem with abnormal lenticels colonized by C. tabebuiae sp. nov.; B, pycnidium with rostrate-vermiform ostiole neck; C, group of conidia. Scale bars: B, 30 µm; C, 10 µm.