Dendrophoma cytisporoides Sacc., Michelia 2: 4. 1880.

Dendrophoma cytisporoides Sacc., Michelia 2: 4. 1880. Figure 12 View Figure 12

≡ Phoma cytisporoides Sacc., Michelia 1: 522. 1879.

≡ Phoma cytisporoides subsp. punicina Sacc., Michelia 2: 273. 1881.

≡ Dendrophoma cytisporoides var. punicina (Sacc.) Sacc., Syll. fung. 3: 180. 1884.

≡ Dendrophoma cytisporoides var. pruni-virginianae Sacc., Riv. Accad. di Padova 33: 169. 1917.

= Dendrophoma punicina (Sacc.) Sacc., Rabenh. Krypt.-Fl., Edn. 2, 1(6): 409. 1901.

Description on the natural substrate.

Teleomorph: Ascomata perithecial, non-stromatic, immersed becoming erumpent, in small groups or dense caespitose clusters on the bark of the host, 120-150 μm diam, 180-200 μm high, subglobose to broadly conical, dark brown, glabrous, papillate. Ostiole periphysate. Ascomatal wall fragile, carbonaceous, 22-28 μm thick, two-layered. Outer layer of textura prismatica, consisting of brown, polyhedral cells with opaque walls. Inner layer of textura prismatica, consisting of several rows of thin-walled, hyaline, flattened cells. Paraphyses sparse, persistent, septate, anastomosing, 2-2.5 μm wide, tapering to ca. 1-1.5 μm, longer than the asci. Asci (66-)69-88.5(-92) × 6.5-8 μm (mean ± SD = 77.5 ± 5.9 × 7.3 ± 0.5 µm), (35.5-)43.5-63(-69) μm (mean ± SD = 53.9 ± 5.7 µm) long in the sporiferous part, unitunicate, arising from densely branched, short ascogenous hyphae, 8-spored, cylindrical to cylindrical-clavate, stipitate, apically broadly rounded, ascal apex with an indistinct, non-amyloid apical annulus visible only with the PC illumination, ca. 1.5 μm wide, 1.5-2 μm high. Ascospores 8-10.5(-11) × 2.5-3.5 μm (mean ± SD = 9.5 ± 0.6 × 3.0 ± 0.3 µm), fusiform, hyaline, 1-septate, not constricted at the median septum, uniseriate, obliquely uniseriate or partially biseriate in the ascus. Anamorph: Not observed.

Description on OA.

Colonies effuse, vegetative hyphae hyaline, 2-3 μm wide. Conidiomata stromatic, globose becoming cupulate, up to 350 μm diam. Setae absent. Conidiophores macronematous, septate, branched or unbranched, up to 60 μm long, hyaline. Conidiogenous cells 7-13 × 1.5 μm, monophialidic, integrated and terminal or discrete and lateral, subcylindrical, single or in terminal whorls, hyaline, tapering to ca. 1 μm; collarettes indistinct. Conidia 2.5-3.5 × 1-1.5 (mean ± SD = 3.1 ± 0.3 × 1.2 ± 0.1 µm), naviculate to botuliform, with 0.5-1 μm long setulae at each end, aseptate, smooth-walled, in slimy droplets, hyaline in mass.

Culture characteristics.

On CMD colonies 18-20 mm diam, circular, flat, margin entire, velvety-lanose, mucoid at the margin, white, isabelline towards the periphery, reverse white. On MLA colonies 18-21 mm diam, slightly convex, circular, margin entire to fimbriate, lanose, floccose, cobwebby at the margin, white, with an isabelline outer zone of submerged growth, reverse isabelline. On OA colonies 19-21 mm diam, circular, flat, raised margin, margin entire, velvety becoming lanose towards the margin, mucoid at the margin, zonate, colony centre grey to whitish-grey with intermediate white zone becoming brown, beige at the margin, reverse grey. On PCA colonies 13-15 mm diam, circular, flat, slightly convex centrally, margin entire, velvety-lanose, floccose becoming mucoid towards the periphery, white, pale brown centrally, with an isabelline outer zone of submerged growth, reverse isabelline. Sporulation absent on all media after 4 wk; abundant on OA and PCA after 10 wk or 4 mo, respectively, on MLA sterile primordia of conidiomata were formed.

Specimen examined. Germany • 16 Jan. 2012; on bark and wood of a dead twig of Buxus sempervivens ; R. Schumacher leg.; ( PRA-16322, culture CBS 144107 = IMI 506817).

Habitat and distribution.

Saprobic on decaying wood and bark of Buxus sempervivens , Deutzia scabra , Rhododendron sp., and Ulmus sp. The species is known from Europe in France, Germany and the Netherlands ( Saccardo 1879; Sutton 1965; Crous et al. 2012; this study).

Notes.

Our strain sporulated in vitro only after prolonged incubation. On OA it formed globose to pulvinate fertile conidiomata, while on PCA the conidiomata often became confluent. The comparison of ITS and 28S sequences of our strain with those of the epitype strain of D. cytisporoides CBS 223.95 ( Crous et al. 2012) confirmed they are conspecific; the two strains share 100 % sequence similarity.