iNaturalist is the world’s most popular citizen science platform for biodiversity. Keen naturalists have now photographed almost half a million mites, but this number is even higher, as many insects are also photographed bearing their acarine guests. Careful, and even quick, perusal of these photographs can provide surprising and satisfying insights into the distribution, hosts and life histories of insect-associated mites. Here, I focus two studies that used iNaturalist records to support specimen-based taxonomy on two poorly-known families of trigynaspid mites found in Australia, but I also give other examples of how iNaturalist can provide evidence and make new discoveries. The first example is Micromegistus, known previously from the USA, South America, New Zealand and undescribed specimens in Australia. Using iNaturalist, I showed that this genus is widespread in New Zealand where it uses various carabids, and occasionally tenebrionids, as hosts. In Australia, however, these mites have a strong preference for the carabid tribe Pterostichini that live in rainforests along the eastern coastline. The second example is Promegistus, which iNaturalist photographs also show are restricted to the eastern rainforests of Australia, but show a strong preference for the genus Pamborus. Photographic records also show microhabitat preferences, provide evidence of kleptoparasitic feeding, and support the notion that the type locality and host were wrong for the previous sole species of the family, Promegistus armstrongi. As minor examples, I show how photographs helped emphasise that larval Neotrombidium are subelytral parasites by the absence of these mites in thousands of photos, yet were common under the elytra of pinned museum specimens. iNaturalist can also find extraordinary mites in surprising localities, such as the bizarre Reginacharlottia on an amblypygid in New Caledonia, a genus with a curious global distribution that encompasses South and Central America and Lord Howe Island. In all cases, these citizen science data have provided exemplary supporting evidence and new knowledge to these specimen-based taxonomic studies.