Identification and taphonomy of spores of coprophilous fungi in Reiherbachtal (Naturpark Solling-Vogler, Germany)

Spores of coprophilous fungi (SCF) preserved in sediments are increasingly used as indicators of past herbivore activity and grazing intensity. However, uncertainties remain regarding both the identification of SCF and the influence of taphonomic processes. This pilot study aimed to (1) improve the taxonomic resolution of SCF records using a morphotype-based approach and (2) evaluate the effects of taphonomic processes by comparing SCF assemblages among primary substrates and secondary depositional environments. Modern samples were collected in the pastoral forest of Reiherbachtal (Naturpark Solling-Vogler, Germany). A total of 30 SCF morphs were described, 11 of which could be linked to fungal taxa using a previously established reference collection. This enabled a refinement of several non-pollen palynomorph (NPP) types and demonstrated that a morph-based approach can improve the ecological interpretation of SCF records. Comparison among substrates revealed that fresh and incubated dung contained the highest diversity and abundance of SCF, whereas mosses and lake sediments contained more diverse fungal assemblages. Several hyaline spore types abundant in dung were absent from moss and sediment samples, indicating selective loss during taphonomic processes and/or laboratory preparation. Nevertheless, the dominant SCF morphotypes occurred in all investigated substrates, and the composition of SCF assemblages in mosses and lake sediments broadly reflected the assemblages observed in dung, despite substantially lower spore concentrations. The results support the use of SCF assemblages as indicators of local grazing activity and highlight the importance of further investigations of SCF taphonomy when reconstructing past herbivore presence from sedimentary spore records.