New records of Polymeridium (Müll. Arg.) R. C. Harris from Brazil with description of a new species from the Caatinga, and a checklist of the Brazilian species Author C, Bruno Micael Author Barbosa, ardoso Author A, Lidiane Author Santos, lves dos Author Oliveira, Isaías de Author Junior Author Oliveira, Dayane de Programa de Pós-Graduação em Biologia de Fungos, Universidade Federal de Pernambuco Departamento de Micologia, Recife, Pernambuco brunomicael _ @ hotmail ldn. stalves @ gmail isaiiasjr @ gmail dayanelimaday @ hotmail brunomicael_@hotmail Author Lima Pernambuco, (Brazil). com. com gmail. com. com Author Aptroot, André Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Avenida Costa e Silva, s / n Bairro Universitário, CEP 79070 - 900, Campo Grande, Mato Grosso do Sul (Brazil) andreaptroot @ gmail. com andreaptroot@gmail.com Author E, Marcela Author S, ugenia da Author Cáceres, ilva text Cryptogamie, Mycologie 2024 2024-03-15 20 4 39 46 https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/mycologie2024v45a4.pdf journal article 10.5252/cryptogamie-mycologie2024v45a4 1776-100X 10824656 Polymeridium stromatocorticatum B.Barbosa, Aptroot, L.A.Santos & M.Cáceres , sp. nov. ( Fig. 1 ) Polymeridium differing from all known species in the genus by a corticate thallus and aggregated ascomata; ascospores 3-septate, 23-26 × 5.5-6.5 µm. TYPE MATERIAL . — Brazil • Bahia , Raso de Catarina ; on tree bark; 10.X.2021 ; leg. L.A. Santos ; holotype : ISE [ ISE 54094 ]; isotype : ABL . ETYMOLOGY . — Named after the stromatic ascomata and the corticate thallus, both unique characters within the genus. MYCOBANK . — MB852549. DESCRIPTION Thallus crustose, up to 3 cm diam., corticate, ochraceous, surrounded by a 0.2 mm wide brown prothallus line. Ascomata closed, 0.3-0.4 mm diam., aggregated in groups of 2-10, black, fused with walls sideways, without crystals; walls c . 30 µm thick. Ostioles apical, with a whitish grey pruina. Hamathecium not inspersed. Ascospores 8/ascus, 3-septate, hyaline, 23-26×5.5-6.5 µm, lumina rectangular; surrounded by a c . 1 µm thick gelatinous sheath. This species is characterized by the combination of a corticate thallus and aggregated ascomata, while the ascospores display the typical features of a Polymeridium . Chemistry: thallus KOH-negative, UV-negative; no substances found. CHECKLIST OF POlYMeRidiUM SPECIES FROM BRAZIL