Ditiola haasii Oberw., Zeitschrift

Zamora, Juan Carlos & Holec, Jan, 2021, Ditiola haasii (Basidiomycota, Dacrymycetaceae) - taxonomy and ecology of a rare species from Central Europe, Phytotaxa 522 (2), pp. 121-130 : 123

Ditiola haasii Oberw., Zeitschrift für Mykologie 55(2): 205, 1989 Figs. 1–4

Holotype. Germany, Bavaria, Allgäu, Oberjoch , elev. 1200 m, leg. L. Kisimova-Horovitz & F. Oberwinkler, collection FO 31799, 20 Sep 1981 (herbarium M; not studied by us).

Basidiomata turbinate to ± discoid or cushion-shaped when hydrated, sessile to stalked, centrally attached to the substrate by a rooting cord that may not be very conspicuous, ca. 1–4.5 mm in diameter and 1–3 mm high (estimates derived from re-hydrated material), whitish to pale yellow when fresh, strongly gelatinous, with a shiny, slightly roughened, well-delimited cortex, and a pruinose hymenium, collapsing onto the substrate when dried as a thin, brittle, pale yellowish to orangish layer. Cortical and marginal hyphae thin-walled, clamped, with ± cylindrical terminal cells, 2.5–4 µm in diameter, simple to sparsely branched. Internal hyphae mostly thin-walled, with smooth walls and clamped, but some hyphae becoming thick-walled towards the base. True hyphidia probably absent, only some thin-walled, unbranched hyphidia-like cells observed among the basidia, probably representing young basidial growths. Basidia cylindric to slightly attenuated towards the base, thin-walled and clamped, becoming bifurcate by the development of two sterigmata. Mature basidial body 31–45 × 4–5(5.5) µm, sterigmata 18–55 × 2.5–3.5 µm. Basidium apex frequently U-shaped, without or with a barely developed apical protuberance. Basidiospores narrowly ellipsoid-allantoid to cylindric-allantoid, (10.5)11–16 × 5–6.2 µm, thin-walled, inamyloid, becoming 0–3 septate at maturity. Microconidia ovoid, ca. 2–2.5 × 1.5–2 µm. Cell cytoplasm frequently showing very conspicuous and strongly refractive lipid drops, especially in basidia and basidiospores, which are hyaline or have a yellowish hue.

Figures

FIGURE 1. Ditiola haasii, Boubínský prales, PRM 944647. For details see Collections studied. Photo J. Holec.

FIGURE 2. Ditiola haasii, detail, Boubínský prales, PRM 944647. Photo J. Holec.

FIGURE 3. Ditiola haasii, slightly aberrant basidiomata, Boubínský prales, PRM 922888. For details see Collections studied. Photo J. Holec.

FIGURE 4. Ditiola haasii, micromorphological characters.A: Terminal cells of cortical hyphae. B: Three-septate mature basidiospores. C: Basidiospores with different degrees of septation and microconidia. D–F: Basidia in different degrees of development. A–B and D: PRM 944647; C, E–F: PRM 922888. Scale bars: 10 µm. Photos J.C. Zamora.