Tephromela vinacea L.A.Santos, Aptroot, Lücking & M.Cáceres, 2023

Santos, Lidiane Alves dos, Aptroot, André, Souza, Maria Fernanda de, Lücking, Robert, Guzmán-Guillermo, Jorge & Cáceres, Marcela Eugenia da Silva, 2023, Four new species of Tephromela M. Choisy (Ascomycota, Tephromelataceae), three containing lichexanthone, from Brazil and Mexico, Cryptogamie, Mycologie 20 (2), pp. 11-25 : 18-20

Tephromela vinacea L.A.Santos, Aptroot, Lücking & M.Cáceres , sp. nov.

( Figs 3E, F ; 4C, D )

Similar to Tephromela atra but corticolous and differing in the presence of a fatty acid, and in the wine-red pigment in the upper hymenium and epihymenium.

HOLOTYPE. — Brazil. Pernambuco, Buíque, Parque Nacional Vale do Catimbau , alt. 745 m, 8°30’41”S, 37°16’37”W, on bark of tree, 13-15.VIII.2017, L.A. Santos s.n. (holo-, ISE [ ISE46534 ]).

ADDITIONAL SPECIMENS EXAMINED. — Brazil. Pernambuco, Buíque, Parque Nacional Vale do Catimbau , alt. 745 m, 8°29’49”S, 37°18’02”W, on bark of tree, 13-15.VIII.2017, L.A. Santos s.n. ( ISE [ ISE54172 ]); Mato Grosso do Sul, Fazenda Marambaia, Bonito , alt. 650 m, 20°58’S, 56°42’W, on wood, 30.X.2018, A. Aptroot 77088 ( ABL, CGMS); Fazenda Santa Fé, Jardim , alt. 650 m, 21°32’S, 56°45’W, on bark of tree, 02.XI.2018, A. Aptroot 77478 ( ABL, CGMS); Bonito, outskirts, near tower, alt. 475 m, 21°07’44”S, 56°30’41”W, on bark of tree, 09.XI.2018, A. Aptroot 78049 ( CGMS).

ETYMOLOGY. — The species is named after the wine-red pigmented gel that surrounds the paraphyses.

CHEMISTRY. — Apothecia and medulla UV+ greenish white, C-, P-, K-. Alectoronic acid, atranorin and an unknown hydrophobic substance detected by TLC. This unidentified fatty acid has an RF value of 18 in solvent C.

ECOLOGY AND DISTRIBUTION. — On exposed tree branch in Caatinga vegetation in NE Brazil and on trees and especially wooden poles in Cerrado in S Brazil; known only from Brazil, but probably occurring in adjacent countries.

MYCOBANK. — MB 846316.

GENBANK. — OP881896.

DESCRIPTION

Thallus crustose, whitish to pale ochraceous-grey, rimose to areolate, minutely verrucose, somewhat glossy, c. 0.1 mm thick. Prothallus black to greyish-white or absent. Photobiont an unicellular green alga, arranged in one layer below the cortex, algal layer 37-70 µm high. Apothecia always present, sessile, roundish, homogeneously distributed on the thallus, with somewhat unevenly crenate, sometimes lobate margin. Disk black, 0.5-2 mm in diam., flat to slightly convex, epruinose. Thalline margin concolorous with the thallus, c. 0.3 mm wide, raised above the level of the disk (100-125 µm). Proper exciple thickest at the base, becoming thinner at the edges, pale to intense yellow-brown, intensifying yellow in K. Exciple with crystals that after treatment with K partly or completely dissolve. Hymenium c. 63-100 µm thick, pale wine red. Epihymenium dark wine red, K+ intensifying wine red. Paraphyses simple, septate, 2-3 µm wide, with 4-6 µm wide hyaline apical cells, surrounded by wine red pigmented gel. Subhymenium 37.5-50 µm thick, brown. Hypothecium 62-87.5 µm thick, golden brown. Asci slightly clavate, 40-55 µm tall, 8-spored. Ascospores simple, hyaline, ellipsoid, 10-13 ×5-8 µm. Pycnidia black. Conidia rod-shape, 12.5-15 × 1 µm.

DISCUSSION

The new species superficially resembles Tephromela atra , but differs in secondary chemistry and is not closely related to the latter phylogenetically ( Fig. 2 ). Fatty acids were first reported for the genus in Muggia et al. (2014). At the time, the authors did not describe the material as a new taxon and questioned the application of chemical characters in the delimitation of species within the genus. Subsequently, based on the presence of fatty acid, Cestaro et al. (2016) described T. pacifica . Kantvilas (2015) and Kantvilas & Elix (2017) also recently used chemical patterns to describe new species with unique chemistry. The metabolite found in our species is a fatty acid, as reported by Cestaro et al. 2016, but has a chemical standard, with a RF value of 18 in solvent C, different from that found by Cestaro et al. (2016) with a RF value of 50.

Most similar to the new species are T. alectoronica , described from Australia but in the protologue also reported from Brazil, and T. rhizophorae Kalb , described from Brazil. Both lack fatty acids but contain traces of physodalic acid instead. The ascospores of T.rhizophorae are distinctly smaller (8-10×5-6 µm) whereas those of T. alectoronica are only slightly larger (12- 17 ×6-9 µm). Thus, without co-chromatography, T. vinacea L.A.Santos, Aptroot, Lücking & M.Cáceres , sp. nov. and T. alectoronica are difficult to distinguish. The specimen clustering as sister to T. vinacea L.A.Santos, Aptroot, Lücking & M.Cáceres , sp. nov., and here named T. aff. vinacea ( Fig. 2 ) is of interest in this respect. It presents a UV+ greenish white fluorescence, although alectoronic acid was not clearly detectable with TLC. It was collected at one of the localities where Kalb (2008) originally reported material identified as T. alectoronica (Chapada dos Guimarães, Mato Grosso). Thus, Kalb’s material might be conspecific with this sequenced specimen, which would imply that the Brazilian material of T. alectoronica is not that species but is represented by the clade here named T. aff. vinacea , quite distant from the Australian T. alectoronica ( Fig. 2 ). However, given that the underlying specimen is rather small and the chemistry could not be determined with certainty, we refrain from any formal conclusions in this case.

Figures

FIG. 3. — Habitus and UV reaction: A, B, Tephromela multireflexa Aptroot & M.F.Souza, sp. nov. (holotype), apothecial margins UV+ yellow and UV+ bluish green; C, D, Tephromela obesimarginata L.A.Santos, Aptroot & M.Cáceres, sp. nov. (holotype), thallus and apothecium margin UV+ yellow; E, F, Tephromela vinacea L.A.Santos, Aptroot, Lücking & M.Cáceres, sp. nov.(holotype), medulla UV+ greenish white; G, H, Tephromela xanthonica Guzmán-Guillermo,sp.nov. (holotype), thallus and apothecium margin UV+ yellow. Scale bars: 2 mm.

FIG. 4. — Section ascomata: A, B, Tephromela obesimarginata L.A.Santos, Aptroot & M.Cáceres, sp. nov. (holotype), before and after KOH treatment; C, D, Tephromela vinacea L.A.Santos, Aptroot, Lücking & M.Cáceres, sp. nov. (holotype), before and after KOH treatment; E, F, Tephromela xanthonica Guzmán- Guillermo, sp. nov. (holotype), before and after KOH treatment. Scale bars: 100 μm.

FIG. 2. — Phylogenetic relationship of Tephromela M.Choisy based on maximum likelihood analysis of ITS rDNA sequences.Bootstrap support values are reported below branches. The new Tephromela species are indicated in boldface. GenBank accession numbers are given in Table 1.