Saturday, September 29, 2018

Mosquito and Other Bites


Did you ever wonder what a mosquito bite looks like close up?  So did I, so here it is.  I felt it land on my arm, probably the movement of the hairs.  I had been photographing other little insects gnawing on me this weekend so it only took about 30 seconds to get my camera out and change the settings.  She wasn't bothered in the least with having a big camera two inches away.

While I was working one handed with the camera, she (only female mosquitoes bite) was searching under my epidermis for a blood vessel.  Once found, she injected saliva with anticoagulant to insure that the blood would keep flowing into her proboscis.  So far, this can be painless but my body's immune system had been alerted and it released histamine at the site.  This caused the sting and the subsequent  swelling.  When you slap, you probably have her saliva on board so just hope she hasn't been promiscuous with a disease carrier!

"I can't believe I drank that much"  (After 2 minutes)
National Geographic has more detailed information on how the proboscis works.  Frequently compared to a hypodermic needle, it is much more complex than that.  For one thing it is very flexible, bending and twisting in the tissue under the epidermis.  Rather than a hollow tube, it is a sheath that introduces 6 mouth parts under the skin.  A pair of mandibles and another pair of maxillae (same name as your jaw) grip the skin so it can push deeper in the search for blood.  Their video even shows the blood vessel compressing as the red cells are drawn in.

Last week we were in Bob Ranney's back yard when I grabbed at a slow flying insect.  We argued about what it was as it was bigger than the mosquitoes we see at Bull Creek, but as usual he was right.  This turned out to be an Asian Tiger Mosquito, Aedes albopictusIt arrived in Texas in 1985 and spread rapidly, now extending from Oklahoma and Missouri to Pennsylvania. (CDC)  They can range from 3-10mm depending on food size, so Bob's was well fed.
"This mosquito has become a significant pest in many communities because it closely associates with humans (rather than living in wetlands), and typically flies and feeds in the daytime in addition to at dusk and dawn. The insect is called a tiger mosquito for its striped appearance, which resembles that of the tiger."  Wikipedia.
Lacewing larva
Most of the species I photograph giving me little bites are never identified.  I am excluding wasps, predaceous diving beetles and hellgrammites. These are bites that require an immediate response, coupled with an announcement such as "*&^%$, you **&#@."  My favorite minor bite was from the lacewing larva on the right which let go just before the picture.  It seemed to have nothing to gain from subduing me and I suspect it was just curious.  Aside from the tick below that was slurping up my juices the others are unidentified.  Any suggestions are welcomed.

Unknown digging in.
Unknown biting hand that fed it

Tick at lunch