Podapolipidae

Podapolipidae is a family of mites.^[1] All members of the family Podapolipidae are specialized obligate external (and rarely internal) parasites of various insects,^[2] among which at least 20 genera are subelytral ectoparasites of different beetle families, mainly Carabidae, Chrysomelidae, Coccinellidae, and Scarabaeidae.^{[3][4][5][6][7]}

Podapolipidae
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Superorder:	Acariformes
Order:	Trombidiformes
Family:	Podapolipidae

These mites are sexually transmitted, i.e. the motile stages of the mite (larvae or adult females) move from one host individual to another during copulation.^[8] Parasitisation with these mites can negatively affect host fitness. For example, in some ladybirds, individuals parasitised with Coccipolipus suffer lower fecundity and egg viability^[8] and sometimes reduced longevity.^[9] Beyond this, these mites can modify host sexual and behavioural traits to boost their transmission success among individual hosts.^[10] For example, in the milk weed leaf beetle, males parasitized by Chrysomelobia tend to more frequently contact other males, and are more successful in mating competition compared to unparasitised males; and this facilitates the mite’s higher transmission rate.^[10][5]

Four genera of Podapolipidae are exclusively associated with carabid beetles: Dorsipes (22 species), Eutarsopolipus (99 species), Ovacarus (3 species) and Regenpolipus (5 species).^{[11][12][13][14][15][16]} Apart from Ovacarus, which is an endoparasite of the reproductive tracts of some carabids, the rest are subelytral ectoparasites.^[12] Species of Eutarsopolipus are versatile in morphology and are currently grouped into ten species groups.^[17] Most of the species are specific to a single host species. However, a few parasitize more than one host species^[18] or more rarely more than one genus,^[13] yet the possibility of them being cryptic species remains untested. More interestingly, in some cases more than one species can parasitize one host species^[17] and sometimes they are specialized to different microhabitats such as the elytral cavity, on hindwings or on the dorsal abdomen of their host.^[19][5]