Dermanyssoidea is a superfamily of mites, including most of the mites which parasitise vertebrates.

Families

Dermanyssoidea contains 21 families: The familial composition is debated. For example, a 2010 analysis found Spelaeorhynchidae and Spinturnicidae to be more closely related to Eviphidoidea than to Dermanyssoidea.

Description

Dermanyssoidea are morphologically variable. For example, within Dermanyssus (Dermanyssidae) alone, there are some species that are compact and sclerotised with short and stout legs, while others are soft-bodied (to allow engorgement with blood) with reduced shields and slender legs. Like mites in general, Dermanyssoidea have a pair of chelicerae, but the size and shape of cheliceral segments and digits is highly variable across the superfamily. Spelaeorhynchidae and Spinturnicidae are highly modified morphologically for living on bats, with Spelaeorhynchus praecursor (the first known species of Spelaeorhynchidae) initially being mistaken for a tick due to its appearance. Similarly, the laelapid Sphaeroseius ecitophilus looks like a spider, not a mite, and was misidentified as a spider initially (Brucharachne ecitophila).

Parasitism

This superfamily engages in various forms of parasitism on a wide range of hosts. Some mainly inhabit animal nests and move onto hosts only to feed, while others live on hosts permanently. In the former group, there are facultative parasites that may feed on a host but are normally predacious, and obligate parasites that must feed on a host.

Disease transmission

Due to their parasitism, some Dermanyssoidea are vectors of disease-causing pathogens. They are known or suspected to transmit viruses, bacteria, protozoans and nematodes. Most of these vectors are in families Dermanyssidae, Macronyssidae and Laelapidae.

Phylogeny

A 2010 analysis suggests that parasitism evolved independently at least eight times within Dermanyssoidea.