Asterina brigadeirensis A.L. Firmino & O.L. Pereira, sp. nov.
Index Fungorum number: IF 900066; MycoBank number: MB 900066; Facesoffungi number: FoF 13383; Fig. 1
Etymology – Name refers to the mountain range, where the fungus was collected, Serra do Brigadeiro.
Holotype – VIC 44217
Sexual morph: Colonies amphigenous, circular to irregular, single to confluent, dark brown, black, 0.1–5 mm diam. Hyphae straight to slightly flexuous, branching irregularly, brown, septate, hyphal cells cylindrical, 4.5–7.5 μm diam., smooth. Appressoria numerous, entire to lobate, sessile, lateral, alternate to unilateral, never opposed, globose to pyriform, unicellular, straight to angular, 7.5–10×6–9.5 μm, brown, penetration peg central on the appressorial cell. Ascomata superficial, thyriothecia, scutiform, on top of mycelial mat, circular to ellipsoid, single to confluent, fringed at margins, randomly distributed in the colony, 135–262.5 μm diam., opening by a central star-shaped fissure to an irregular fissure, dark brown to black; wall of textura radiata to irregulate on cells isodiametric to cylindrical. Pseudoparaphyses cylindrical, filiform, septate, unbranched, hyaline, up to 2.5 μm wide. Asci bitunicate in structure, fissitunicate, disposed as an upright palisade layer, ovoid to cylindrical, 8-spored, hyaline, 65–95 × 35–45 μm. Ascospores cylindrical to oblong, ends rounded, straight or slightly arched, 1-septate, constricted at the median septum, hyaline, becoming brown at maturity, verruculose, 30–35×12.5–16 μm. Asexual morph: Not observed.
Material examined – Brazil, Minas Gerais, Araponga, on living leaves of Miconia cinnamomifolia Naudin (Melastomataceae), 10 September 2014, A.L. Firmino (VIC 44217, holotype).
GenBank numbers – MZ475298 (LSU)
Notes – Asterina brigadeirensis differs from the species previously reported on Melastomataceae (Léveillé 1845; Hennings 1904, 1909; Theissen 1912, 1913; Sydow and Sydow 1916; Yates 1917; Maublanc 1920; Ryan 1924, 1928; Sydow 1927, 1930; Sydow and Petrak 1929; Chardón and Toro 1930; Orejuela 1944; Petrak 1950; Hansford 1954; Yamamoto 1957; Hosagoudar and Abraham 2000). It is closest to A. venezuelana, which has smaller and ovoid to conoid appressoria, smaller and ovoid to clavate asci, and smaller and dark brown ascospores. Asterina brigadeirensis is easily separated from A. amadelpha, A. belluciae, A. centroniae, A. chrysophylli, A. confertissima, A. hypophyla, A. maublancii, A. melanotes, A. melastomatis, A. melastomatis-candidi, A. memecylonicae, A. pulla, A. schlechteriana, A. sinsuieiensis, A. uribei in having verruculose ascospores. Asterina antioquensis is distinct from the new species in having ovoid to ellipsoid appressoria, smaller asci, and smaller ascospores with an upper third septum. Asterina astroniae has narrow hyphae, smaller and ovoid appressoria, smaller and subglobose to ovoid asci, and finally smaller ascospores. Asterina denigrata differs from Asterina brigadeirensis in the hypophyllous colonies, smaller ascomata and asci with 2–6 spores, and smaller and dark brown ascospores. Asterina hughesii differs in the narrow appressoria, smaller and spatulate asci, lacking pseudoparaphyses, and smaller ascospores. Asterina melastomatacearum differs from Asterina brigadeirensis in the smaller asci, and smaller and ellipsoid-ovoidal ascospores. Asterina madikeriensis differs in the colonies epiphyllous, entire appressoria and smaller ascospores with tuberculate wall. Asterina melastomaticola differs in the narrow hyphae, lacking pseudoparaphyses, and much smaller ascospores with echinulate ornamentations. Asterina miconiae differs from Asterina brigadeirensis in the smaller and cylindrical to subglobose appressoria, smaller and ellipticalclavate asci, and smaller ascospores. Asterina miconiicola differs in the much smaller ascospores with an upper third septum. Asterina theissenii differs in having narrow and dark brown hyphae, cylindrical to hemispherical appressoria, lacking pseudoparaphyses, and much smaller asci and ascospores. Asterina transiens differs from new species in the cylindrical appressoria, smaller and elliptical asci, and much smaller ascospores. Asterina venezuelana differs in the narrow and dark brown hyphae, smaller and ovoid to clavate asci, and smaller and dark brown ascospores. Finally, Asterina lopi, described below differs from the new species in having smaller and cylindrical to globose appressoria, smaller and ovoid to subclavate asci, and much smaller ascospores. (Léveillé 1845; Hennings 1904, 1909a; Theissen 1912, 1913; Sydow and Sydow 1916; Yates 1917; Maublanc 1920; Ryan 1924, 1928; Sydow 1927, 1930; Sydow and Petrak 1929; Chardón and Toro 1930; Orejuela 1944; Petrak 1950; Hansford 1954; Yamamoto 1957; Hosagoudar and Abraham 2000; Hosagoudar 2006). Based on our phylogenetic analyses (Fig. 2) and morphological analyses, herein we introduce a new species, A. brigadeirensis. Asterina brigadeirensis is the tenth species of Asterina reported on hosts belonging to Melastomataceae in Brazil, and the twelfth on Miconia.
Figure 1 – Asterina brigadeirensis (VIC 44217, holotype) a Colony with open thyriothecia and surface mycelium. b Ascomata opened by a central starshaped fissure. c Cross section of the ascomata. d Globose to pyriform unicelular appressoria. e Immature ascus with pseudoparaphyses. f Mature ascus. g Immature ascospores. h Brown and verruculose ascospore. Scale bars: a=200 µm, b–c=50 µm, d–e–f=20 µm, d=10 µm, g–h=10 µm
Figure 2 – The phylogenetic tree was obtained by Bayesian inference methods using the sequences of the LSU region. The posterior probability values are indicated at the nodes. Strain numbers are indicated after species names. New sequence data is in bold and blue. The analyses included 33 strains including representative genera of Asterinalesstricto sensu and Asterinales lato sensu. The tree is rooted with Venturia populina (CBS 256.38) and V. inaequalis (CBS 815.69) (Pleosporales) as outgroup