Here's why:

* Two long flagella: Euglenoids are known for having one or two long, whip-like flagella that help them move.

* Nuclei: Euglenoids have a single nucleus (though some species may have more than one). However, the presence of multiple nuclei in a blood smear suggests a parasitic infection.

* Blood smear: While Euglenoids are typically found in freshwater environments, some parasitic species can infect animals, including humans.

Important Note: It's crucial to understand that identifying a protozoan based solely on a brief description can be difficult. A proper diagnosis requires further investigation and laboratory analysis. It's always best to consult with a qualified medical professional for any suspected parasitic infections.