Corethromyces Thaxt.

Santamaria, Sergi & Pedersen, Jan, 2021, Laboulbeniomycetes (Fungi, Ascomycota) of Denmark, European Journal of Taxonomy 781, pp. 1-425 : 218-219

Genus Corethromyces Thaxt.

MB#1245

Proceedings of the American Academy of Arts and Sciences 27: 36 ( Thaxter 1892). –

Type species: C. cryptobii Thaxt.

Eucorethromyces Thaxt., Proceedings of the American Academy of Arts and Sciences 35: 433 ( Thaxter 1900) [MB#1919]

Brief description

Monoecious. Receptacle three-celled. Primary appendage free, consisting of several superposed cells bearing lateral branches, some of them giving rise to intercalary but also terminal antheridia. Cells II and VI superposed, separated by a ± horizontal or oblique septum. Perithecium with four cells in each vertical row of outer wall cells.

Remarks

This is a large genus consisting of 92 species, of which 13 in Europe, three in Denmark. The most recently described species are C. gibbosus and C. marshallii (Rossi et al. 2020) . Hughes (2008) reported two undescribed species from Ptiliidae and Byrrhidae . Although Tavares (1985) redefined the too broad generic characteristics of the original description ( Thaxter 1892), it is still a genus with poorly defined limits. Corethromyces subsigmoideus Speg. ( Spegazzini 1917) is included here among the 92 species, although Tavares (1985) suggests that it could be a Cryptandromyces . Most species are associated with Col. Staphylinidae , but also with Carabidae , Leiodidae, Heteroptera Lygaeidae ( De Kesel & Haelewaters 2019) , and Diptera Sphaeroceridae (Rossi et al. 2020) . The number of perithecial wall cells may be questioned according to Weir & Hughes (2002) who mentioned five tiers instead of four at least in C. diochi Thaxt. ( Thaxter 1931) ; moreover, these authors suggested that the genus might be separated into two subgroups.

Key to the Danish species (partially following Santamaria 2003)

1. Basal cell of the receptacle (I) blackish brown, extending laterally into a black outgrowth. On Rugilus (Col. Staphylinidae ).................................................................................................... C. stilici Thaxt.

– Basal cell of the receptacle (I) not fully darkened, without a lateral expansion............................... 2

2. Basal cell of the appendage dark, supporting a few-celled axis bearing lateral slender phialides. Perithecial apex without a dark preapical spot. On Tachyporus Gravenhorst, 1802 (Col. Staphylinidae )..................................................................................... C. bialowiezensis T.Majewski

– Basal cell of the appendage mostly entirely pale (rarely partially darkened), carrying several crowded sterile and fertile branches, the latter bearing intercalary phialides. Perithecium with a dark preapical spot. On Choleva (Col. Leiodidae ) .................................................... C. henrotii Balazuc ex Balazuc