Short Communication Ephebe brasiliensis (Ascomycota, Lichinaceae): an overlooked freshwater lichenized fungus

Ephebe brasiliensis is a semi-aquatic fruticose cyanolichen that occurs in freshwater environments from Brazil (Minas Gerais and São Paulo states) and Uruguay. Although this species may be locally abundant and has “wide” distribution, it has been poorly studied and is still misunderstood with respect to their distribution and ecological characteristics. Herein, E. brasiliensis is reported for the first time in Southern Brazil. artigo, primeira

Lichens with cyanobacteria as the main photobiont are commonly known as cyanolichens and correspond to a small group gathering approximately 12% of lichen-forming fungal species (Rikkinen 2003).
Other cyanolichens recorded in Brazil are also still poorly known in relation to their taxonomy, ecology, and mainly their actual distribution within of the country. These include Peltula Nyl., Jenmania W. Wächt., Leprocollema Vain., Pyrenopsis (Nyl.) Nyl. and Ephebe Fr., whose species are recorded for few localities, most often only in very succinct species list (e.g., Vainio 1890;Osorio & Homrich 1978;Fleig 1995;Spielmann et al. 2007). Overall, the actual distribution and ecological features of these taxa are poorly understood.
The knowledge about semi-aquatic lichens (which remain submerged for a substantial amount of time) is even more incipient in Brazil. Even though many crustose lichens from freshwater and marine habitats were reported in Europe and USA (e.g., Verrucaria Schrad.; Orange et al. 2009;Peltigera hydrothyria Miadl. & Lutzoni;Brodo et al. 2001), only informal observations indicated that this fascinating group of lichens also occurs in freshwater and marine habitats in Brazil (author's personal field experience, unpublished data). This is the first attempt at the semi-aquatic lichens from Brazil. Many questions about these lichens still remain unclear, and we suggest the following references for more information (e.g., Hawkswoth 2000;Shearer et al. 2007;Nash 2008).
Ephebe brasiliensis was currently only known for two localities in Brazil, the type locality in the state of Minas Gerais (Vainio 1890;Henssen 1963;Aptroot 2002) and in the state of São Paulo (Henssen 1963), as well as one single locality in Uruguay (Osorio 1975) (Fig. 1). These localities are over 1000 km apart in a North-South line, and the wide range of environments between them demonstrates the lack of information about the species distribution. This report records now Ephebe brasiliensis in Southern Brazil and aim to contribute with information about its distribution, taxonomy, and ecological features.
Specimens were collected using a knife, stored in paper bags, and dried at room temperature. They were examined using standard stereoscope (20-40×) and light microscope (100-1000×) techniques. Freehand sections of the thalli were mounted in water. The spot tests (K, C, KC and P), observations under UV light, and thin layer chromatography (TLC) using solvent system C were conducted according to Huneck & Yoshimura (1996) and Orange et al. (2001). The distribution map ( Fig. 1) was produced in QGIS Software 2.0.1, according to a tutorial developed by Calegari et al. (2016).   Henssen (1963). Fig. 2 Description. Thallus fruticose, caespitose, black to bluish black, shiny when wet and somewhat olive opaque when dry, up to 3 cm tall in the field, up to 1.5 cm tall when dry, something gelatinous when wet and brittle when dry, homoiomerous, ecorticate; branches terete, (90-)105-180 µm thick, solid, surface smooth to somewhat rough, branching mainly anisotomicdicotomic, sometimes trichotomic and rarely tetracotomic, apices usually curved, frequently with up to 6 tiny branches. Photobiont with true branching. Ascomata and pycnidia not found.
Substrate and ecology. Most specimens were found on rocks in montane water streams, with at least a thin layer of freshwater (Fig. 3). Specimens from the state of Santa Catarina were found in semi-aquatic conditions (Fig. 2a), while some specimens, including those from the state of Rio Grande do Sul, were found submersed up to 0.4 m. Nevertheless, they can survive out of the water during dry periods (Fig. 2b). Locally, this species is abundant, forming a large population that can occupy several square meters. In Brazil, Ephebe brasiliensis is a freshwater lichen that can be recognized even when it is sterile. It is characterized by the black to bluish black fruticose thallus, containing Stigonema species as photobiont, with (90-)105-180 µm thick branches. According to Vainio (1890) and Henssen (1963), the species have lecanorine apothecia, lateral to terminal, up to 0.5 mm diam., with 16-spored asci, ascospores simple, colorless, ellipsoid, 9-16 × 4-7 µm (immature in asci). The conidia are cylindrical, 2.5-3 × 1 µm. This species can be found on rocks, submerged or not, in semi-aquatic or aquatic environments.
As previously known, lichens are excellent environmental bio monitors (e.g., Cislaghi & Nimis 1997;Nash 2008). Therefore, we recommend that Ephebe brasiliensis would be included as a key species for future biomonitoring and water quality investigations due to its occurrence in conserved areas (i.e. National Parks). Future studies are important for conservation strategies of the species, and we postulate that E. brasiliensis probably presents an even wider distribution in South America.
The first author thanks Dr. Matthias Schultz (University of Hamburg, Germany) for taxonomic confirmation of specimens from Santa Catarina.