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 Chitonomyces aculeifer Speg. MB#150989 Fig. 20A–B Anales del Museo Nacional de Historia Natural de Buenos Aires 27: 44 ( Spegazzini 1915b ; as aculeiferus ). Type : “ Sobre las patas del Laccophilus virescens , pescado en el lago de Tarzo, Veneto , Ag. 1914”; LPS . [ Italy ] Chitonomyces bruchii Speg. ( Spegazzini 1917: 479 ) [MB#166509] Chitonomyces ceratomycetalis Thaxt. ( Thaxter 1926: 517 ) [MB#260283] Diagnostic features Dimorphic. In the typical form the perithecium bears a conspicuous straight to strongly arcuate or sigmoidal darkened horn-like outgrowth arising from the preapical wall cell in the posterior margin ( Fig. 20A , arrow). [Detailed descriptions: Scheloske 1969 ; Majewski 1994b ; Santamaria 2003 ; De Kesel & Haelewaters 2012 ] Distribution and hosts On Haliplus , Peltodytes Régimbart, 1878 (Col. Haliplidae ), Laccophilus ? ( type of Ch. aculeiferus ) and Graptodytes (Col. Dytiscidae ) from Europe : Czech Republic , Germany , Italy , Poland , Spain , Bulgaria ( Rossi et al. 2019a ), Belgium ( De Kesel & Haelewaters 2012 ), as well as in South America ( Argentina , type of Ch. bruchi ) and Asia ( China , type of Ch. ceratomycetalis ). Collections examined from Denmark On Graptodytes bilineatus (Sturm, 1835) (Col. Dytiscidae ) DENMARK Nordøstsjaelland (NEZ) Amager Faelled ; 55°38.631′ N , 12°34.729′ E ; UB47; 22 Apr. 2018 ; JP 1037 ; JP det.; ZMUC C-F-123553 . On Haliplus ruficollis (Degeer, 1774) (Col. Haliplidae ) DENMARK Lolland, Falster, Møn (LFM) Busemarke Mose ; 54°57.688′ N , 12°26.619′ E ; UA39; 19 Aug. 2019 ; JP 1495 ; JP det.; ZMUC C-F-124082 , C-F-124083 . Remarks First record from Denmark . It is broadly accepted that this species exists in two “growth forms” or “morphotypes” related to the sex of the host and growth position on the body. The typical horned form grows under the margins of the pronotum or neighbouring areas in females, and the not horned form grows between the anterior or medium claws in males.