What is the Color of Mosquito Blood?

Mosquitoes don't have blood like humans and other mammals. Instead, they possess hemolymph, a fluid analogous to blood found in arthropods such as insects. This hemolymph is clear to yellowish in color. The red color sometimes observed after a mosquito bite comes from the human blood the mosquito ingested, not from the mosquito's own internal fluid.

Hemolymph is primarily composed of water and contains a mixture of substances including ions, pigments, carbohydrates, lipids, glycerol, amino acids, and hormones. The absence of hemoglobin, the iron-containing protein that gives human blood its red color, accounts for hemolymph's light color.

Key Differences from Mammalian Blood

• Hemoglobin Absence: Hemolymph lacks hemoglobin, which is crucial for oxygen transport in mammalian blood. Insects utilize a different system for oxygen transport.
• Color: The color difference stems from the lack of hemoglobin. Mammalian blood is red due to the presence of oxygenated hemoglobin.
• Function: While both transport nutrients and waste products, the specific functions and components differ significantly.

The Red Color Misconception

The misconception that mosquito blood is red arises from observing red fluid after a mosquito bite. This is actually the mosquito's ingested human blood, not its own hemolymph. Jumping spiders, for example, preferentially target mosquitoes that have recently fed on blood, attracted by the red color of the ingested blood. (Blood-red colour as a prey choice cue for mosquito specialist).