May 2 - Trypanosoma evansi

Trypanosoma evansi was the first pathogenic trypanosome that was discovered and infects a very wide range of other mammals, including horses, camels, sheep, goats, buffalo, deer, dogs, and cats. It causes a disease known as "surra", named from an Indian word for "heavy breathing" because infected animals are often weak and lethargic. The taxonomy of this species is in a bit of flux. A sexually transmitted parasite of horses, Trypanosoma equiperdum, was synonymized with T. evansi, but T. evansi, may actually be part of Trypanosoma brucei. This is undoubtedly yet another example of parasite species originally being given distinct names depending on what kind of host animal they were found in and where they were found, but later, via molecular data, being found to have different relationships and thus names.