Find the word definition

Wikipedia
Trimastix

Trimastix is an Excavate genus, the sole occupant of the order Trimastigida. There are few known species, and the genus's role in the ecosystem is largely unknown. However, much interest in this group is related to its close association with other members of Anaeromonadea. Like other members of this order, these organisms do not have classical mitochondria. As such, much of the research involving these microbes is aimed at investigating the evolution of mitochondria.

One species is Trimastix pyriformis.