Likely mosquito bite

Mosquitoes breed in stagnant or slow-moving water and occur in humid outdoor and indoor environments worldwide.

Females usually take blood meals from vertebrates; males feed on nectar and other plant sugars. The blood meal supports egg development.

Most are active at dawn, dusk, or night, though some bite during the day. Females locate hosts through carbon dioxide, body heat, and odor, then lay eggs in water.

Bites commonly cause short-lived itchy, raised redness; scratching can cause secondary infection. Some species transmit diseases such as West Nile, dengue, malaria, or Zika; adults and larvae also serve as food for wildlife and help pollinate plants.