Laboulbeniomycetes (Fungi, Ascomycota) of Denmark Author Santamaria, Sergi Unitat de Botànica, Departament de Biologia Animal, de Biologia Vegetal i d’Ecologia, Facultat de Biociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès (Barcelona), Spain. sergi.santamaria@uab.cat Author Pedersen, Jan Natural History Museum of Denmark (Zoological Museum), University of Copenhagen, Universitetsparken 15, 2100 København Ø, Denmark. japedersen@snm.ku.dk text European Journal of Taxonomy 2021 2021-11-26 781 1 425 http://dx.doi.org/10.5852/ejt.2021.781.1583 journal article 10.5852/ejt.2021.781.1583 2118-9773 5828924 Tanmaurkiella pselaphi Santam. gen. et sp. nov. MB#840613 Fig. 64 Diagnosis Axis with almost parallel margins, apparently rigid, cells not inflated. Perithecium narrowly fusiform. Trichogyne stump forming a horn-like protuberance ( Fig. 64D–F , ts). Etymology The species epithet is derived from the name of the host insect ( Pselaphus ). Type material Holotype DENMARK – Nordøstsjaelland (NEZ) • On Pselaphus heisei Herbst, 1792 (Col. Staphylinidae Pselaphinae ); Lejre ; 55°36.245′ N , 11°58.315′ E ; PG86; 10 May 1895 ; Chr. Engelhart Dry0099 ; Chr. Engelhart det.; ZMUC C-F-124165 . Description Thallus hyaline, except for the slightly darkened perithecium. Basal cell of receptacle (I) obconical, with a blunt pale brown, rather undefined foot at base ( Fig. 64F , fo), about 1.5 times as long as broad. Suprabasal cell of receptacle (II) sometimes subdivided, where the second, rarely the third cell ( Fig. 64G , black line), gives rise to perithecium. Appendage unbranched, very elongate, apparently rigid, with parallel margins, far exceeding the perithecial apex, starting from the cell bearing the perithecium consisting of up to 15 superposed cells. Lower cells of appendage cylindrical, not inflated, slightly variable in length/width ratio; upper cells of appendage gradually longer and narrowing towards the distal area. Antheridia unknown. Perithecial stalk cell (VI) trapezoidal, slightly longer than broad, separated from cell II that gave rise to it by a strongly oblique to vertical septum. Perithecium narrowly fusiform, with a not very inflated venter and a short, nearly undistinguished neck. Perithecial tip rounded to flat, dome-shaped, showing four preapical protuberances which form a crown-like structure around the preostiolar area ( Fig. 64A–E, H ). Between tiers w 3 and w 4 a horn-like outgrowth represents a conspicuous trichogyne stump ( Fig. 64D, F , ts). Length from foot to apex of perithecium 79–88 µm. Perithecium (including basal cells) 48–57 × 13– 19 µm. Maximum length from foot to appendage apex 163 µm. Thalli were found on the elytra and tergites of the host. Nothing is known about the collecting circumstances of the host. Remarks The host is the same that of Tanmaurkiella huggertii gen. et sp. nov. although the two collections come from localities in different parts of Denmark and were obtained more than 100 years apart. The perithecial apex shows a distal dome-shaped area above the crown-like arranged protuberances that seem to be acellular, i.e., without cytoplasmatic contents, similar to what occurs in the conical tip in species of Acompsomyces ( Santamaria 1993c ) .