<i>Camarosporidiella</i>, a challenge

The genus <i>Camarosporidiella</i> is here assessed with respect to its phylogenetic structure and species composition. More than 160 pure cultures from ascospores and conidia of more than 150 fresh collections, mostly from <i>Fabaceae</i>, were prepared as DNA sources. Molecular phylogenetic analyses of a multigene matrix of partial nuSSU-, complete ITS, partial LSU rDNA, and <i>tef1</i> exon sequences of our isolates and those of previous workers revealed that these markers are insufficient to provide a complete species resolution. From this reduced data matrix, however, we propose synonyms and accept taxa for previously described species, which could not be included in the final phylogenetic tree due to lack of <i>rpb2, tef1</i> intron and <i>tub2</i> sequences. The final phylogenetic tree, which was inferred from a combined nuSSU-ITS-LSU-<i>rpb2</i>-<i>tef1</i>-<i>tub2</i> sequence matrix resolved our isolates into 27 statistically supported phylogenetic species, of which 15 are new. Altogether 34 species are here accepted in <i>Camarosporidiella</i>. Using type studies we stabilise old names, lectotypify <i>Cucurbitaria asparagi, Cucurbitaria caraganae, Cucurbitaria coluteae, Cucurbitaria euonymi, Dichomera elaeagni Hendersonia mori, Sphaeria elongata, Sphaeria laburni</i> <i>Sphaeria spartii</i> and epitypify them as well as <i>Cucurbitaria cytisi, Cucurbitaria retamae</i> and <i>Cucurbitaria steineri</i> to place them in their correct phylogenetic positions and fix their taxonomic concepts. Morphology alone is not suitable to identify these species, and therefore no determinative key to species can be given. However, if hosts are reliably identified, many species can be determined without molecular data. Host images are included with the figures of each fungal species. <b>Taxonomic novelties:</b> <b>New species:</b> <i>Camarosporidiella aceris</i> Jaklitsch & Voglmayr, <i>Camarosporidiella aetnensis</i> Jaklitsch & Voglmayr, <i>Camarosporidiella aragonensis</i> Jaklitsch & Voglmayr, <i>Camarosporidiella asparagicola</i> Jaklitsch & Voglmayr, <i>Camarosporidiella astragalicola</i> Jaklitsch & Voglmayr, <i>Camarosporidiella cretica</i> Jaklitsch & Voglmayr, <i>Camarosporidiella echinosparti</i> Jaklitsch & Voglmayr, <i>Camarosporidiella hesperolaburni</i> Jaklitsch & Voglmayr, <i>Camarosporidiella longipedis</i> Jaklitsch & Voglmayr, <i>Camarosporidiella maroccana</i> Jaklitsch & Voglmayr, <i>Camarosporidiella ononidis</i> Jaklitsch & Voglmayr, <i>Camarosporidiella radiatae</i> Jaklitsch & Voglmayr, <i>Camarosporidiella spartioidis</i> Jaklitsch & Voglmayr, <i>Camarosporidiella sphaerocarpae</i> Jaklitsch & Voglmayr, <i>Camarosporidiella tridentatae</i> Jaklitsch & Voglmayr. <b>New combinations:</b> <i>Camarosporidiella asparagi</i> (Maire) Jaklitsch & Voglmayr, <i>Camarosporidiella caraganae</i> (P. Karst.) Jaklitsch & Voglmayr, <i>Camarosporidiella coluteae</i> (Rabenh.) Jaklitsch & Voglmayr, <i>Camarosporidiella cytisi</i> (Mirza) Jaklitsch & Voglmayr, <i>Camarosporidiella elaeagni</i> (P. Karst.) Jaklitsch & Voglmayr, <i>Camarosporidiella euonymi</i> (Cooke) Jaklitsch & Voglmayr, <i>Camarosporidiella retamae</i> (Pat.) Jaklitsch & Voglmayr, <i>Camarosporidiella steineri</i> (Petr.) Jaklitsch & Voglmayr. <b>New names:</b> <i>Camarosporidiella neomori</i> Jaklitsch & Voglmayr, <i>Camarosporidiella neospartii</i> Jaklitsch & Voglmayr. <b>Citation:</b> Jaklitsch WM, Blanco MN, Rejos FJ, Tello S, Voglmayr H (2025). <i>Camarosporidiella</i>, a challenge. <i>Studies in Mycology</i> <b>111</b>: 19-100. doi: 10.3114/sim.2025.111.02.