Stylostome

A diagram of the stylostome, or the hardened tube of dead cells formed by the larval form of the trombiculidae when feeding on them.

The stylostome is a funnel- or channel-like structure formed in response to trombiculid mites. The formation is not caused by the mouthparts of the mites, because these mites do not have needle-like mouthparts as hematophagous animals have been known to have, but have chelicerae, which only pierce the skin. The tube is formed by the digestive enzymes in the saliva, which are the same salivary secretions that break down cells and cause the surrounding tissue to harden.[1] As the mite feeds longer, the saliva seeps further down, digesting more tissue and causing the stylosome to penetrate to lower layers of skin.[2]

Trombicula mite larva with stylostome
  1. ^ Tally, Steve (2001-07-16). "As chiggers get thicker it's no time to snicker, entomologist says". Purdue University. Retrieved 2019-07-02.
  2. ^ Ambrose, Kevin (2014-09-14). "Gross: The insanely itchy chigger feasts as summer retreats". The Washington Post. Retrieved 2019-07-02.