Abstract
Aim This paper is a response to Li and Xue (2024) regarding the global species richness and distribution of the eriophyoid mites, which are highly host‐specific phytophages. Discussion The number of described plant species is approaching 400,000. This enormous level of plant diversity has played a fundamental role in the diversification of the eriophyoids. Ozman‐Sullivan and Sullivan (2023) estimated there are at least 250,000 eriophyoid species, with most species highly likely to be in the largely neglected subtropical and tropical regions. Li and Xue (2024) argued that there could be far less than 250,000 eriophyoid species. We assert that this high number is realistic and possibly conservative. As an example, Ozman‐Sullivan and Sullivan (2023) reported that just 11 well‐studied plant species collectively host ~200 eriophyoid species. Habitat destruction and climate change represent increasingly dire threats to the existence of thousands of plant species and their dependent eriophyoid species across the world. Location Global. Taxon Eriophyoid mites (Acari: Eriophyoidea). Conclusions We present more evidence to support our estimate of at least 250,000 eriophyoid species, including a substantial tropical majority. We also elaborate on potential research on this subject. The conservation of the invertebrates, including the likely enormous number of undescribed species, is critical to the maintenance of global ecological functioning.