Lithophyllospora australis Selbmann & Coleine, sp. nov.
Index Fungorum number: IF 902389; Mycobank number: MB 902389; Facesoffungi number: FoF 07391; Fig. 1
Etymology: with reference to the South Pole where the fungus was isolated from.
Holotype: MUT 6702; MNA-CCFEE6417
Fungus inhabiting cryptoendolithic communities in Antarctica. Sexual morph: Not observed. Asexual morph: Mycelium composed of brown melanized smooth hyphae, formed by small roundish or cylindrical catenate cells, 4.2–6 μm, diam. Apical growth by enteroblastic elongation. 1–2 celled arthroconidia liberated by rhexolithic or schyzolithic secession or produced by enteroblastic gemination (4.3 × 13 μm, 4.3 × 15 μm, diam). Rare conidiogenous cells (13 to 15 μm, diam) produced by micronematous conidiophores liberating endoconidia brown smooth broadly spherical, 6 to 7 μm diam.
Culture characteristics: Psychrophilic fungus, no growth at 25 °C. Cauliflower-like colonies black obverse and reverse, compact, slightly glittering, with irregular margin, eventually penetrating into the agar. Very slow growing, reaching 12–13 mm diam. in 12 weeks at 15 °C (optimal T).
Material examined: Antarctica, Mt. New Zealand, Northern Victoria Land, collected by Laura Selbmann, January 2016, MUT 6702, holotype=MNA-CCFEE 6417, Culture preserved at − 150 °C and in dried condition.
GenBank numbers: ITS: OQ102327, LSU: OP912972
Notes: Lithophyllospora is now an additional genus in Trichomeriaceae. Similarly, to others, it is very slow growing comparably to Bradymyces and differently from Knufia generally grows more rapidly. Similarly, to the genus Bradymyces, Lithophyllospora australis (type) produces endoconidia, despite not frequently, but differently to any other genus in the same family displays arthroconodiogenesis both through schyzolithic and rexolithic secession. Cladophialophora proteae CPC 14902 isolated from dead leaf tissue of Encephalartos altensteinii (Crous et al. 2008), here groups together with L. australis and similarly displays conidial chains with arthric secession. Based on phylogenetic placement and morphological peculiarities here we introduce a new genus in the Trichomeriaceae and the type species Lithophyllospora australis. Cladophialophora proteae CPC 14902 is here proposed as Lithophyllospora proteae, a different species in the new genus accordingly to its phylogenetic position ecology and geography
Figure 1 – Lithophyllospora australis (MNA-CCFEE 6417, holotype). a Frontal view of the culture. b Reverse view of the culture. c, d Smooth hyphae formed by small sub-globose or cylindrical catenate cells. e Melanized septate conidium enteroblastically germinating; 2 celled conidium and hypha undergone to rhexolithic secession. f, l 1 celled arthroconidia liberated by schizolithic secession. g, i 1- and 2-celled arthroconidia liberated via rhexolitic secession. h, m endoconidia development within a conidiogenous cell. Scale bars: a, b=2 cm, c–m=10 µm