What do you call animals that only eat blood?

Animals that only eat blood are called hematophagous.

This term comes from the Greek words "haima" (blood) and "phagein" (to eat).

Some examples of hematophagous animals include:

* Mosquitoes: Both male and female mosquitoes feed on nectar, but only females bite and drink blood.

* Ticks: These parasites latch onto their host and feed on their blood for extended periods.

* Vampire bats: These bats are known for feeding on the blood of mammals, including livestock and even humans.

* Leeches: These segmented worms are often used in medical procedures for bloodletting.

It's important to note that while these animals primarily feed on blood, they may also consume other things depending on the species. For example, some vampire bats may supplement their diet with fruits.