Bioacoustics of Laboulbenia

Remarks Of all the genera included in the Laboulbeniales , this is the richest in number of taxa, with more than 650 species, in addition to countless infraspecific taxa of highly variable value. We have gathered 653 species in our database catalogue. Song et al. (2019) mentioned 633 species where 40 have been described after 2010, Haelewaters et al. (2019b) reported 650 accepted species and many varieties, and according to the same authors, Index Fungorum (2019) includes 897 names of taxa. More than one hundred species are known in Europe (we count 109 species), 47 have been found in Denmark . The most recently described species are L. chionophila , L. halophila ( Santamaria et al. 2020a ) , L. quarantenae ( Haelewaters & De Kesel 2020 ) , L. angkorensis , L. fusca , L. polyandra , L. scabra , and L. trilobata ( Kong et al. 2020 ) , and L. amblystomi ( Haelewaters et al. 2021 ) . Although species of Laboulbenia mostly occurs on ground beetles ( Carabidae ), some may also be found on other families like Staphylinidae , Gyrinidae , Chrysomelidae , Elateridae , and Corylophidae , even on other orders of Insecta like Diptera , Blattodea , Hemiptera , Hymenoptera, Orthoptera , and unrelated arthropods like mites (Acarina). A subdivision of the genus into subgenera would be desirable, although the difficulty of managing so many taxa, data and intraspecific variability makes it a titanic task. Some attempts were carried out by Spegazzini (1917) , who described several unnatural sections, which were not widely followed by subsequent authors. Unfortunately, his contemporary Roland Thaxter passed away before his sixth monograph dealing with this genus could see the light. This fact led to many new species left out but also a probable reorganization of the genus. Many years after, Tavares (1985) distinguished 20 structural groups of species based on morphology but subgenera were not formally described. Some characteristics are key to distinguish and group species: (1) if the septum IV–V is connected with the septum III–IV, as in L. pedicellata , or not as in L. flagellata ; (2) if the insertion cell is flattened and dark, clearly distinguished from surrounding cells, as in L. ophoni , or pale, colourless, not distinctly contrasting from the surrounding cells, as in L. fasciculata ; (3) whether basal cells of the outer appendage show some septa distinctly darkened and/or constricted, as in L. clivinalis ; (4) if the outer appendage is unbranched, as in L. notiophili , or ± ramified, as in L. elaphri ; (5) if cell V is totally or partially free from the perithecium, as in L. pseudomasei , or connected along its whole length to the perithecium, as in L. vulgaris . Other important features, such as the cells III, IV and V totally or partially undivided, are not found in the Danish species of Laboulbenia .