Paraphoma betonicicola Mlčoch, 2024

Mlčoch, Patrik & Matušinsky, Pavel, 2024, Phylogenetic and morphological revision sexual stages of the genus Paraphoma (Phaeosphaeriaceae) and next related species from clade of Ophiobolus-like (Phaeosphaeriaceae), Phytotaxa 663 (4), pp. 184-204 : 189-191

Paraphoma betonicicola Mlčoch , sp. nov. — Fig. 3

Holotype. BRNM 829885

MycoBank no. 854606

Etymology. Species name “ betonicicola ” refers to substrate specialization on dead stems of the genus Betonica .

Sexual morph. Ascomata pseudothecial, subglobose to globose, in small or numerous groups, subepidermal, (170–)240–280(–370) μm in diam., later semi-immersed to erumpent. Ostioles minute papillate, up to 55 μm high, up to 72 μm in diam. Substrate in surroundings of ascoma with characteristic purpure to light or deeply red coloured. Ascomal wall is composed of several layers of pseudoparenchymatous cells, composed of brown to dark brown, trito polygonate cells of textura angularis, (6–)7–10(–11) × (4–)5–7.5(–9) μm, N = 20. Hamathecium is composed of numerous, indistinct, hyaline, septate pseudoparaphyses, anastomosed above the asci, later absent. Asci bitunicate, 8-spored, cylindrical to cylindric-clavate, short pedicellate, (59–)60.5–70(–75) × 9–10 μm, N =15. Ascospores fusoid, biseriate in ascus, initially hyaline, 3-septate with the second cell enlarged, later brown, 4- to 6-septate with the second to third cell enlarged, without gelatinous sheath, appendages and ornamentation, with several globose lipid drops, (20–)23.5–31(–39.5) × (4.5–)5–6(7.5) μm, Q = 4.2–5.8, Q AV =5, N = 40. Asexual morph. Sporulation in vivo. Conidiomata pycnidial, globose, subepidermal, up to 500 μm in diam. with short ostiole. Conidiomatal wall is composed of several layers of brown to dark brown pseudoparenchymatous cells. Conidiogenous cells were not observed. Conidia ellipsoid to oblong, with rounded ends, hyaline, aseptate, smooth-walled, 4.4–5 × (0.8) 1–1.5 (1.6) μm, N =30.

Culture characteristics. Colony on PDA slow growing, reaching 16 mm in diam. after 2 weeks at 25 ° C, circular to irregular, white at the edge, light grey, grey to greyish black at the centre, concentric coloured, filiform at the edge, elevation raised to convex, no pigment product. Conidiomata in vitro pycnidial, globose, up to 270 μm in diam. and 130 μm high, with conical ostiole, 66 × 50 μm. Conidiomatal wall composed of several layers of brown, pseudoparenchymatous cells, 2.5–2.6 × 2–3 μm, N = 10. Conidia in culture was ellipsoid to fusoid, with rounded ends, hyaline, aseptate, smooth-walled, (4.5–)5–6.5(–7) × 1.5–2.3 μm, Q = 2.5–3.6, Q AV = 3.1, N = 30.

Habitat. On dead stems of Betonica officinalis L. ( Lamiaceae ). All fresh collection was situated in the wet meadows of Molinion caeruleae Koch (Molinio-Arrhenatheretea).

Distribution. Known from the Czech Republic and Austria.

Material examined. THE CZECH REPUBLIC: 1. col. P. Mlčoch, Vítkovská vrchovina Highland, Pustá Polom village, Kaluže, 430 m a. s. l., 10. 7. 2019, on Betonica officinalis, GPS : 49.8613922N, 18.0118833E ( BRNM 829155, GenBank no. OQ359105, strain MLC 04, holotype). 2. col. Dr. Hrubý, as Leptosphaeria haematites , Moravia, 5. 1924, on Betonica officinalis (4814/39); 3. Col. P. Mlčoch, Nízký Jeseník Mts., Hradec nad Moravicí-Kajlovec, Kalvárie hill, meadow, 375 m a. s. l., 25. 8. 2020, on Betonica officinalis, GPS : 49.8565217N, 17.8973406E ( BRNM 840271, paratype). AUSTRIA: 4. col. Dr. Hrubý, det. F. Petrak as Leptosphaeria haematites, Freistadt, Kaltenberg, Weidenau, 1919 , on Betonica officinalis (4815/39); 5. col. Dr. Hrubý det. F. Petrak as Leptosphaeria haematites, Freistadt, Kaltenberg, Weidenau, 1919 , on Betonica officinalis (17611).

Notes. Dr. Hrubý and F. Petrak determined their collections as Leptosphaeria haematites , where it is also purpure to red coloured of the substrate, but this species has always only 3-septate, hyaline ascospores (never with pseudoseptate) and grown only on dead stems of Clematis vitalba ( Ranunculaceae ) (Mlčoch P. 2021). Other similar species belong to Leptosphaeria fiumana , L. purpurea , and Paraphoma rubicunda . Paraphoma rubicunda , which grows on dead stems of Lamiaceae and Apiaceae , has narrower ascospores (22–25 × 3–3.5 μm) and shorter asci (45–60 × 7–8 μm) ( Shoemaker 1984). Leptosphaeria fiumana does not colour substrate; asci are clavate and spore cells to the septum constricted ( Hazslinzski 1893). Leptosphaeria purpurea has shorter ascospores (see table 2). All species have 3-septate ascospores without pseudosepta. Sequences exhibit of 92.72% the similarity with Paraphoma salicis Crous & Akulov in ITS region and 99.5 % similarity in LSU region. P. salicis was isolated from the leaves of Salix alba ( Crous et al. 2021) . In the base on the BLAST results and morphological differences it is a new species.

Figures

FIGURE 3. Paraphoma betonicicola (BRNM 829885).A: pycnides; B: ascoma; C: ascomal wall; D: cultivate on PDA; E, F: asci; G–J, M–R: ascospores; K—conidia in PDA culture; L—pycnides in PDA culture. Scales:A–B: 500 μm; C, E, F: 10 μm; D: 2 mm; G–K, M–R: 5 μm; L: 50 μm.