Parahypoxylon papillatum (Ellis & Everh) M. Cedeno-Sanchez , E. Charria-Giron & M. Stadler, 2023

Cedeno-Sanchez, Marjorie, Charria-Giron, Esteban, Lambert, Christopher, Luangsa-ard, J. Jennifer, Decock, Cony, Franke, Raimo, Broenstrup, Mark & Stadler, Marc, 2023, Segregation of the genus Parahypoxylon (Hypoxylaceae, Xylariales) from Hypoxylon by a polyphasic taxonomic approach, MycoKeys 95, pp. 131-162 : 131

Parahypoxylon papillatum (Ellis & Everh) M. Cedeno-Sanchez, E. Charria-Giron & M. Stadler comb. nov.

Figs 3 , 4

Hypoxylon papillatum Ellis & Everh. in Smith, Bull. Lab. Nat. Hist. Iowa State Univ. 2: 408 (1893). Syn.

Lectotype.

USA. Ohio, Delaware, 21 Jul 1893, A. Commons 2160, rotten wood of Carya (NY [2 pks.], selected by Ju and Rogers (1996).

Epitype.

USA. West Virginia, Mason Co., Bruce’s Chapel, 18 Aug 1983, wood of Acer , J.D. Rogers (WSP 7557; ex-epitype culture ATCC 58729).

MBT no: 10011515.

Teleomorph.

Stromata superficial, effused-pulvinate to plane, with inconspicuous to conspicuous perithecial mounds, up to 12.5 cm long × up to 4 cm broad × 1.8-4.0 mm thick; surface Honey (64) to Isabelline (65), Isabelline (65) to Gray Olivaceous (107), or Isabelline (65) to Olivaceous (48); blackish granules immediately beneath surface and between perithecia, with KOH-extractable pigments Isabelline (65); the tissue below the perithecial layer conspicuous, black, 1.0-2.5 mm thick. Perithecia long-tubular, 0.3-0.4 mm diam × 0.8-1.5 mm high. Ostioles umbilicate. Asci with amyloid, discoid apical apparatus, 1-2 µm high × 3.5 µm wide, stipe up 137-180 µm long × 8-10 µm broad, the spore-bearing parts 93-110 µm long, the stipes 30-80 µm long. Ascospores brown to dark brown, unicellular, ellipsoid, nearly equilateral, with broadly to narrowly rounded ends, 12.0-18.5 × 6.5-9.0 µm, with straight germ slit spore-length; perispore indehiscent in 10% KOH; epispore smooth.

Cultures and anamorph.

Colonies on MEA, OA, and YM covering a 9 cm Petri plate in 2 weeks, with white, flat, mycelium, margins filamentous. Reverse at first white, becoming yellowish at the center. The anamorph has been described by Rogers (1985), but we were unable to confirm the presence of conidial structures when we studied the strain more than 30 years later.

Secondary metabolites.

Stromata contain BNT and cohaerin type azaphilones according to the MS/MS analysis.

Notes.

We were not only able to confirm the morphometric results of Ju and Rogers (1996) but even established that this species is characterized by a rather specific metabolite profile. This species has to our knowledge still not been reported from outside America and seems to be most frequently encountered in the Eastern USA.

Further specimens examined.

USA. Kansas, on decorticated wood, Feb 1884, F.W. Cragin 257 (NY00830462, syntype of H. papillatum ); Pennsylvania, Allegheny Co., on dead wood, 14 Aug 1941, Henry, L.K. 4885 (BPI 591033); Pennsylvania, Meadville, old log, 17 Oct 1922, E.C. Smith 353 (BPI 591030) ; CANADA., on wood, J. Dearness (BPI 591035A, syntype of H. papillatum ) .

Figures

Figure 3. Parahypoxylon papillatum comb. nov. A stroma B ostioles C KOH extractable stromatal pigments D perithecia (cross section) E ascospores with straight germ slits F amyloid apical apparatus in a mature ascus treated with Melzer's reagent G amyloid apical apparatus in an immature ascus treated with Melzer's reagent. Scale bars: 1 cm (A); 10 μm (E-F); 10 μm (G).

Figure 4. Parahypoxylon papillatum comb. nov. (ATCC 58729) Colonies after 2 weeks (A, B) on 2 % MEA (C, D) on OA (E, F) on YM.