The soil microbiome is teeming with diverse microorganisms and fauna. These interact with each other, forming complex and dynamic interrelationships. The soil microbiome includes all soil type-dependent microorganisms, including microfaunal grazers, nematodes and protists (Costa et al., 2018). However, microbial metazoa are rarely considered as a key component in the soil microbiome, and most research focuses on prokaryotic taxa (Bik, 2019). This is mainly due to the complex taxonomy of this microfauna as well as the lack of published molecular data for barcoding (di Montanara et al., 2022). For example, in nematodes, most of the available genome data sets are on parasitic taxa and the model species Caenorhabditis elegans (Zhang et al., 2017; Qing et al., 2020; Powers et al., 2021). Free-living nematodes, which predominate in the soil microbiome, are understudied: they are in a ‘Goldilocks zone of neglect’ (Bik, 2019).