Morphological species of Gloeandromyces (Ascomycota, Laboulbeniales) evaluated using single-locus species delimitation methods

In this paper, new species and formae of the genus Gloeandromyces (Ascomycota, Laboulbeniales) are described and illustrated. These are: Gloeandromyces dickii sp. nov. on Trichobius joblingi from Nicaragua and Panama; G. pageanus f. alarum f. nov. on Tri. joblingi from Panama; G. pageanus f. polymorphus f. nov. on Tri. dugesioides and Tri. joblingi from Panama and Trinidad; and G. streblae f. sigmomorphus f. nov. on Tri. joblingi from Panama. Gloeandromyces pageanus on Tri. dugesioides from Panama as described in Nova Hedwigia 105 (2017) is referred to as G. pageanus f. pageanus. Support for these descriptions of species and formae comes from phylogenetic reconstruction of the large subunit ribosomal DNA and from the application of species delimitation methods (ABGD, bPTP, GMYC). Host specialization results in phylogenetic segregation by host species in both G. pageanus and G. streblae and this may represent a case of incipient speciation. A second mechanism driving diversity involves position-induced morphological adaptations, leading to the peculiar morphotypes that are associated to growing on a particular position of the integument (G. pageanus f. alarum, G. streblae f. sigmomorphus).