Rhynchophoromyces hydrobii T.Majewski, Acta Mycologica Laboulbeniomycetes (Fungi, Ascomycota) of Denmark Santamaria, Sergi Pedersen, Jan European Journal of Taxonomy 2021 2021-11-26 781 1 425 3DBPY (T. Majewski) I. I. Tav. [510,1077,1711,1739] Laboulbeniomycetes Ceratomycetaceae Eusynaptomyces Fungi Laboulbeniales 29 30 Ascomycota species hydrobii  MB#105312  Fig. 3B–D    Mycologia Memoirs9: 220 ( Tavares 1985). – Basionym:  Rhynchophoromyces hydrobiiT.Majewski, Acta Mycologica7(2): 274 ( Majewski 1972a) [MB#322804]. –    Type: “ On metasternum of  Hydrobius fuscipesL.(Col., Hydrophilidae): Lomianki Dolne, Nowy Dwor Maz.county, small water body south of village,  24.4.1970, leg. T. Majewski”; KRAM. (fig. 7a – holotype,…) ( TM 245, Majewski, 2008: 69). [ Poland]    Diagnostic features Receptacle very variable in length and number of cells, consisting of 11–80 superposed cells. Perithecium nearly straight to ± arcuate, with an almost undistinguished venter, tapering distally to an undifferentiated, rounded apex. [Detailed descriptions: Sarna & Milewska 1978; Majewski 1994b]    Distribution and hosts Only known from Polandon  Hydrobiusand  HydrophilusGeoffroy, 1762(Col. Hydrophilidae).    Collections examined from Denmark  On  Hydrobius rottenbergiiGerhardt, 1874(Col. Hydrophilidae)   DENMARK–  Nordøstsjaelland(NEZ)• Amager Faelled; 55°38.631′ N, 12°34.729′ E; UB47;  15 Apr. 2018;  JP1036; JPdet.; ZMUC C-F-123552.    Remarks First record from Denmark. Second world record, the first outside the typecountry. The separation of this species from reduced forms of  Eusynaptomyces benjaminiiScheloskeis difficult because such thalli lack the horn on the perithecial apex, which is not the case for the Danish thalli. The host was previously considered as a subspecies of  Hydrobius fuscipes. A photo of this species is given here for the first time. 4988640540 On metasternum of Hydrobius fuscipes L. 1970-04-24 KRAM T. Majewski Poland Nowy Dwor Maz. Lomianki Dolne 29 30 TM 245 1 holotype 4988641630 2018-04-15 JP Denmark JP 55.64385 Amager Faelled 1 12.578816 31 32 ZMUC C-F-123552 1 Nordostsjaelland