Term now generally used instead of “leptomonad” or “leptomonad stage,” to avoid confusion with the flagellate genus Leptomonas. It denotes the flagellate stage of a trypanosomatid protozoan in which the flagellum arises from a kinetoplast in front of the nucleus and emerges from the anterior end of the organism; usually an extracellular phase, as in the insect intermediate host (or in culture) of Leishmania parasites.
[pro- + G. mastix, whip]
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