Identifying and naming non-pollen palynomorphs

Palynological slides usually contain numerous remains of fungi, algae, plants, and animals, collectively referred to as non-pollen palynomorphs (NPPs). Even experienced palynologists often struggle to identify all of these palynomorphs or decide how they should be labelled in a way that ensures clarity and comparability across studies. We synthesise existing approaches to studying NPPs with particular emphasis on their definition, identification, and nomenclature. We demonstrate a conceptual broadening of the term non-pollen palynomorphs, which has direct consequences for both identification and naming practices. NPPs in pollen slides are considered as morphological entities (morphs), defined here as the specific morphological characteristics of a microfossil that has undergone fossilisation and/or laboratory treatment. Combining existing morph-based frameworks (dinocysts, pollen, chironomids, fungi, and the NPP type-number approach), we propose a hybrid system for treating NPPs. It relies on the morphology of NPPs and can be taxon- and/or life stage-independent, but incorporates relationships between NPPs and biological taxa whenever possible. The proposed conceptual framework and practical recommendations should reduce ambiguity in taxonomy and nomenclature and facilitate the harmonisation of NPP data across studies and palaeoecological databases. Overall, it is intended as a starting point for broader discussion within the community and should encourage palynologists to pay attention to these common but largely ignored constituents.