Cytospora tatrensis and two more new fungi described from Poland

Fifty-three new species, three of them Polish

Fungal Planet is a collective format: each description sheet runs to between two and four pages, is prepared by a different team, and carries its own colour plate and its own tree. The instalment numbered 1868 to 1920 appeared online on 21 January 2026 and sits in the June 2026 issue of Persoonia, volume 56, pages 1 to 173, under the names of 107 authors from Pedro W. Crous to Johannes Z. Groenewald. Each of its fifty-three sheets names one new species, and three of them — 1870, 1903 and 1910 — erect a new genus as well, so the instalment carries fifty-six new names in all. Three sheets rest on type material collected in Poland. The abstract lists them together under the heading Poland: Cytospora tatrensis from dead stems of Pinus mugo, Myxotrichum flavum on resin of Picea abies, and Symphoricola tarnoviensis, which brought a new genus with it. The paper is open in PubMed Central.

Two institutions in Kraków produced the Polish sheets: the Department of Forest Ecosystems Protection at the University of Agriculture, and the W. Szafer Institute of Botany of the Polish Academy of Sciences. All three holotypes went into the KRAM herbarium at the latter, and all three ex-type cultures into the CBS collection.

Sheet 1874: a dead stem of dwarf mountain pine

Cytospora tatrensis Jankowiak & Stępniewska occupies sheet 1874, pages 24 to 26, registered in MycoBank as MB 860581 and placed in the Cytosporaceae, order Diaporthales. The author citation carries two names even though three people signed the sheet — Robert Jankowiak, Hanna Stępniewska and Piotr Bilański — because only the first two are part of the name. The type is recorded in a single line: Poland, South Poland, Tatry Mts, isolated from a dead Pinus mugo stem, July 2023, collected by Cz. Bartnik. The holotype is KRAM F 60043 and the ex-type culture CBS 152107; one further culture, CBS 152108, is listed as additional material.

Everything in the description comes from culture. No sexual morph was observed. On potato dextrose agar the fungus builds globose, mostly clustered pycnidia (549–)682–1285(–1653) μm across, divided into numerous irregular locules (122–)168–326(–452) μm in diameter. The conidia are hyaline, allantoid, smooth and aseptate, measuring (4.1–)4.4–6.0(–8.1) × (0.8–)1.1–1.4(–1.7) μm. Colonies average 42.2 (± 0.4) mm after seven days at 25 °C on that medium, and the sheet records no growth at all at 5 °C. The etymology is one sentence long: the name refers to the fungus occurring in the Tatra Mountains, within the Western Carpathians.

Six loci were sequenced — ITS, LSU, ACT1, RPB2 (which the type statement misprints as RBP2), TEF1 and TUB2. Two details deserve to be stated rather than tidied away. ITS and LSU share the accession PX260479 because a single 1,973 base-pair read spans part of the small subunit, the whole ITS region and part of the large subunit. And the sheet disagrees with itself about the tree: the Notes describe a five-marker data set while the figure legend names six genes. The honest thing to report is how many loci were sequenced, not how many entered the analysis. The tree placed the ex-type isolate close to Cytospora bugeanae and Cytospora pinea, both described from diseased branches of Pinus bungeana in China.

What the sheet does not settle

The Notes say only that the fungus was isolated from shoots showing dieback symptoms in the Polish Tatras, citing the team’s own earlier study from 2024. No pathogenicity test appears anywhere in the sheet. Isolating a fungus from a sick shoot establishes that it was there; it does not establish that it did the damage, and C. tatrensis has not been shown to kill dwarf mountain pine. The distinction is easily lost in retelling: the Polish edition of National Geographic, reporting the description on 17 March 2026, wrote that a species unknown to science was parasitising the infected shoots, and added that the fungus had been given a name alluding to the surnames of its discoverers. The protologue says neither thing: its etymology points at the Tatras, and the surnames after the binomial are the authority, the tag every described taxon carries.

The locality is likewise thinner than it looks. The published type statement gives nothing beyond South Poland, Tatry Mts — no valley, no altitude, no slope. Coordinates do exist, but outside the paper: the GenBank record for the ex-type strain carries 49.21603 N, 19.76886 E and an altitude of 1,584 m. Anyone who uses those figures should credit the database rather than the description. The range of roughly 1,550 to 1,800 m that circulated in the Polish press is a statement about the altitudinal belt in which dwarf mountain pine grows, not about where this collection was made. The same GenBank record differs from the sheet twice over, giving August 2023 rather than July and the core parenchyma of a symptomatic shoot rather than a dead stem. Where the two disagree, the protologue governs.

It is also worth saying what this fungus is not. It is not something a walker could find: it is known from pycnidia grown on agar and from hyphae, and no fruit body visible to the naked eye has been recorded. The epithet says where the type came from, not where the species lives, and its nearest known relatives were described from China. Finally, the announcement by Tatra National Park on 12 March 2026 is bylined by Robert Jankowiak himself and states that the work was part-financed from forest-fund money transferred to the park. It is an author’s text hosted by the institution the funding passed through, not independent confirmation.

Spruce resin, and a snowberry in Tarnów

Myxotrichum flavum Czachura & Piątek, sheet 1894 on pages 84 to 86, MB 861008, was described from resin of Norway spruce collected on 16 October 2020 in the Psarski Dół strict protection area of Świętokrzyski National Park. The holotype is KRAM F-60051 and the ex-type culture CBS 154543. Its colonies are vividly yellow, reaching 16 mm across after two weeks at 15 °C on malt extract agar and 18 mm after two weeks at 25 °C. The sheet states plainly that this is the first member of the genus isolated from conifer resin, and immediately guards the claim: Myxotrichum resinae, described by Elias Fries from spruce resin in Sweden in 1832, is a different fungus, now placed in Phaeoblastophora, with black colonies and a pigmented asexual morph.

The third sheet introduces a genus and a species at once. Symphoricola Piątek, Czachura & Stryjak-Bogacka (MB 861009) belongs in the Teratosphaeriaceae, class Dothideomycetes, and its type species is Symphoricola tarnoviensis (MB 861010, holotype KRAM F-59997, ex-type culture G209 = CBS 152427). The type material was gathered on 1 October 2018 in Tarnów-Piaskówka, in municipal greenery, from a sooty mould community on the leaves of snowberry. The fungus was isolated from that mixed surface film; nothing in the sheet claims it dominates the film or harms the shrub. It makes only hyphae and chlamydospores, (6–)7–16(–20) × 6–13.5(–17) μm, some of them holding endoconidia of 3.5–6.5 × 3–5.5(–6) μm. It grows very slowly: after four weeks the colonies measure 9 mm at 15 °C and 10 mm at 25 °C on malt extract agar, 12 mm at 15 °C and 9 mm at 25 °C on potato dextrose agar.

Following the record yourself

Each of these names can be traced without a subscription. The MycoBank numbers identify the registration of the name, the KRAM accessions point at physical specimens in the Kraków herbarium, the CBS numbers at living cultures, and the GenBank accessions at sequences anyone can compare. The Cytospora tatrensis sheet adds supplementary files on figshare and an alignment and tree deposited in TreeBASE.

One thing cannot be shown here. Persoonia volume 56 is released under CC BY-NC-ND 4.0, which forbids commercial use and derivative works, so the sheets’ colour plates — including the photographs of dying dwarf-pine shoots and the micrographs of conidia — cannot be reproduced on this page. The photograph above therefore shows the host plant and its habitat, and not the fungus.

There is a cheaper observation to end on. Two of the three Polish types came from protected ground, but the third — the one that yielded a new genus — came off a shrub planted in municipal greenery in Tarnów. New genera of fungi do not live only in nature reserves. They also live on a shrub beside a pavement, where nobody had yet arrived with a sample tube.