Mosquito bites are small bumps that can sometimes be found on human skin.
History in Description
In March 1992, while investigating deaths of victims from the Class of '89, FBI Special Agent Dana Scully worried that some small bumps on her lower back were actually raised red welts that were characteristic of the doomed classmates but Scully's FBI partner, Special Agent Fox Mulder, identified the marks as being mosquito bites. After Scully asked whether he was sure of his prognosis, Mulder replied positively, adding that he himself had also gotten eaten up a lot outside. The prognosis of the marks being merely mosquito bites relieved Scully. (TXF: "Pilot")
During an hallucination in 1999, Angela Schiff made several complaints - including that she had mosquito bites - to her husband, Wallace Schiff, moments after they had apparently returned to a mountain cabin after seemingly having been walking outside together. (TXF: "Field Trip")