Species differentiation in the genus Leishmania by morphometric studies with the electron microscope.

Morphometric comparison of some ultrastructural features of leishmanial amastigotes demonstrated species-characteristic differences. These occurred in parameters relating to size, such as diameter and microtubule number; statistical analysis resolved four groups from the seven isolates studied. The results were not inconsistent with previous measurements, mostly with the light microscope, by other workers. The unqualified assertion that Leishmania species are morphologically identical is therefore no longer valid.