Larsons

In the Ariducene, many warm blooded animals developed thicker coats. Thicker hair protects them from the four main problems for anything living in areas other than the tropics. These issues are wind, cold, dust, and the sun. The only problem is the parasites. 

Larsons (sarcoptes larsoni) are a species of mite descended from modern scabies mites. They first evolved in the rocky mountains but have spread to all over North America as well as Asia. Females measure in at .55 mm in length while males come in at .3 mm in length. What differentiates them from their ancestors is that they are far more intense. Their mouthparts are larger in order to burrow through the thicker skin of many desert animals. 

Whenever a new host comes in contact with the original, it doesn't take long for the mites to spread. Once they make contact with the host, they feed off of its blood and dead skin. The females mature faster than their ancestors and take just as long to mature as the males. They lay their eggs inside of their burrows and take about a week to hatch. They also use burrows to dispose of waste.

The symptoms are extreme and the most common areas of infection are the face and legs. First, the burrowing trails and eggs cause itchiness, bumps, and rashes. Then the itchiness turns to large callouses around infected areas. During this process, the hair isn't lost because it protects the mites. The only ways to get rid of the mites is to have other symbiotic bugs eat them or to drown them.