Jana Kocourková

The lichenicolous Phoma species (coelomycetes) on Cladonia

The lichenicolous Phoma species on Cladonia are revised. A statistical analysis of the conidial size suggests that three species are involved: P. cladoniicola sp. nov. a common and wide- spread species in the Northern Hemisphere occurring on a wide range of Cladonia species; P. foliaceiphila sp. nov. known from C. foliacea and C. fimbriata in Europe; and P. grumantiana sp. nov. known from C. symphycarpia and C. mateocyatha in Svalbard and the USA.

Disentangling the complex of Lichenothelia species from rock communities in the desert

Rock-inhabiting fungi (RIF) are melanized, meristematic fungi which dwell on and within rocks and have adapted to withstand harsh conditions in extreme habitats worldwide. Their morphological and genetic diversity remained unknown for a long time, but in the past few years culture-dependent and molecular phylogenetic approaches have contributed to uncovering the species richness of these otherwise very inconspicuous fungi. Only a few taxa of RIF develop both sexual reproductive structure (fertile stromata and/or pycnidia) and show multiple life styles, interacting with algae and lichen thalli in different ways. The genus Lichenothelia is one of these: It is characterized by fertile stromata and pycnidia and by species which can grow on and within exposed rocks, optionally associating with algae, with some species also being lichenicolous. The genus Lichenothelia includes up to now 25 species and form a monotypic family (Lichenotheliaceae) and order (Lichenotheliales) in Dothideomycetes. Here we focused on a group of Lichenothelia taxa distributed in the hot arid region of the Sonoran and Mojave Deserts in the Joshua Tree National Park in California. We performed molecular and morphological analyses and culture isolation and considered the ecology of the environmental samples to disentangle five species. We present the revision of two species already described, Lichenothelia calcarea and L. convexa, and introduce three new taxa to science, L. arida, L. umbrophila and L. umbrophila var. pullata.

A new Lichenostigma species (Genus incertae sedis) from southern California

Abstract Lichenostigma saxicola, growing on silicate rocks and lichens, is described from southern California from both the Sonoran and Mojave deserts as well as from the Santa Monica Mountains on the coast. The species belongs to the subgenus Lichenostigma, has a non-amyloid centrum, and dark one-septate ascospores, 10–12 × 5–6 µm, cells equal or not, constricted at the septum, the walls of over-mature ascospores becoming granular-verrucose. The species is considered facultatively lichenicolous, not host specific, and is pathogenic.

Acaroconium punctiforme gen. sp. nov., a new lichenicolous coelomycete on Acarospora species and Sarcogyne regularis

The coelomycete Acaroconium punctiforme gen. sp. nov. is described from four members of the lichen-forming family Acarosporaceae, three species of Acarospora and Sarcogyne regularis. The new fungus is characterized by pycnidial conidiomata with a distinct ostiolar collar, enteroblastic conidiogenesis, and the production of simple brown conidia. The separation of the fungus from other somewhat similar pycnidial fungi growing on lichens and plant material is discussed.

Two Superficially Similar Lichen Crusts, Gregorella humida and Moelleropsis nebulosa, and a Description of the New Lichenicolous Fungus Llimoniella gregorellae

Abstract: Vondrák, J., Palice, Z., Mareš, J. & Kocourková, J. 2013. Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa, and a description of the new lichenicolous fungus Llimoniella gregorellae. — Herzogia 26: 31–48. Although some characters distinguishing Gregorella humida and Moelleropsis nebulosa were previously known, sterile specimens and specimens with poorly-developed apothecia are often difficult to separate. We provide morphological and anatomical characters that will allow reliable determination of such difficult collections. The most important character for determination of sterile thalli is the shape of the mycobiont cells in the thallus granules. A key summarizes the diagnostic characters of G. humida and M. nebulosa (and some similar species). The Nostoc photobiont in G. humida is morphologically similar to Nostoc from M. nebulosa but the two are not closely related within the genus. The ecology of both lichen species is similar, but there are differences in the preference for differently acidic substrates and in co-occurring bryophytes and lichens. In Central Europe, M. nebulosa was frequently collected in the first half of the 20th century, but there are few recent records, whereas G. humida was only occasionally collected before the last two decades, but is now regularly collected. Moelleropsis nebulosa rarely hosts lichenicolous fungi, though we have seen Lichenochora mediterranae (previously known only on Fuscopannaria) and Sarcopyrenia sp. on it. Gregorella humida rarely hosts a single lichenicolous fungus, described here as Llimoniella gregorellae, spec. nova, which causes obvious harm to host thalli; ITS sequences indicate that it belongs in Leotiomycetes.

A new species of Placocarpus (Verrucariaceae) from southern California

A new species, Placocarpus americanus, is described from the Santa Monica Mountains in Southern California. It is a juvenile parasite on Protoparmeliopsis muralis and differs from Placocarpus schaereri in having smaller non-halonate ascospores, a negative iodine reaction of the medulla, lack of inspersion of the medulla with small crystals, and having a thallus of dispersed areoles.

Four new Lichenicolous Fungi from North America

Abstract. Stigmidium xanthoparmeliarum and Weddellomyces xanthoparmeliae are reported new to California and North America. Lichenostigma amplum and L. bolacinae are reported new for California and North America north of Mexico.

Conspicuous similarity hides diversity in the Acarospora badiofusca group (Acarosporaceae)

Abstract Acarospora badiofusca has an irregularly areolate thallus with an uninterrupted algal layer; it is a montane species and occurs in Asia, North America and Europe. Acarospora boulderensis differs from A. badiofusca in having a squamulose thallus, an interrupted algal layer and a higher hymenium. Acarospora boulderensis was considered a synonym of A. badiofusca by North American taxonomists, but is here recognized as a distinct species occurring in North America. Acarospora asperata H. Magn. is revised as a synonym of A. boulderensis. Acarospora irregularis from central Europe (Czech Republic, Hungary and Slovakia), as well as Greece and Italy (Sardinia), was considered a synonym of either A. badiofusca by Weber or of A. nitrophila by Clauzade and Roux. It differs, like A. boulderensis, from A. badiofusca in having a squamulose thallus, an interrupted algal layer and usually a higher hymenium. However, A. irregularis differs from A. boulderensis in having wider hyphal bundles interrupting the algal layer and distinct algal palisades. Acarospora badiofusca var. lepidioides is synonymized with A. irregularis.

Lichenological notes 2: Lichenothelia convexa, a poorly known rock-inhabiting and lichenicolous fungus

Lichenothelia convexa, a saxicolous and lichenicolous microfungus, is reported new for the Czech Republic. The poorly known species is provided with a description and is illustrated.

A new lichenicolous lichen from Europe and western North America in the genus Dimelaena (Physciaceae)

Abstract Dimelaena lichenicola is a juvenile parasite on D. oreina and D. thysanota, developing an independent brown areolate lichenized thallus on gneiss and acid rock. It differs from D. californica primarily in producing longer conidia (6.0–10.0 × 1.0 vs. 5.0–6.0 × 1.0 µm), having a reduced thallus and minute lobes, lacking a well-developed plicate margin and a prothallus, having a different host species (D. oreina and D. thrysanota vs. D. radiata), and a different habitat (montane vs. coastal). It is reported from North America (California) and Europe (Italy).