Genus Trenomyces Chatton & F.Picard MB#5531 Comptes Rendus Hebdomadaires des Séances de l’Académie des Sciences 146: 201 (Chatton & Picard 1908). – Type species: T. histophthorus Chatton & F.Picard. Brief description Dioecious. Female and male thalli consist of a two-celled receptacle terminated by a two-celled apiculate appendage where the upper gives rise to several fertile branches which grow and corticate producing perithecia or antheridia. Cell I subspherical, forming a conspicuous haustorium. Blackened foot absent. Perithecia and antheridia as in Dimeromyces and Dimorphomyces. Remarks The genus consists of 11 species described on Mallophaga (biting lice of birds and mammals) (Phthiraptera) and Hippoboscidae (louse flies of birds and mammals) (Diptera). Six in Europe, one in Denmark. No new species have been described since T. aquaticus, T. helveticus and T. thaxteri by Eichler (1951). This genus seems understudied probably because of the difficulty to collect suitable hosts. Thaxter (1926) and more recently Tavares (1985) studied this genus in some depth, and the latter added a critical list with insect hosts, vertebrate hosts, and fungi. Eichler (1936, 1939, 1943a, 1943b, 1951, 1952) added abundant information but his descriptions were too brief and drawings too schematic. The genus requires a deep and detailed further study.

Published as part of Santamaria, Sergi & Pedersen, Jan, 2021, Laboulbeniomycetes (Fungi, Ascomycota) of Denmark, pp. 1-425 in European Journal of Taxonomy 781 on page 307, DOI: 10.5852/ejt.2021.781.1583, http://zenodo.org/record/5828924