https://pmc.ncbi.nlm.nih.gov/articles/PMC9840391/
Taxonomic review of Saguinus mystax (Spix, 1823) (Primates, Callitrichidae), and description of a...
Although the Amazon has the greatest diversity of primates, there are still taxonomic uncertainties for many taxa, such as the species of the Saguinus mystax...
https://www.merriam-webster.com/dictionary/mystax
MYSTAX Definition & Meaning - Merriam-Webster
The meaning of MYSTAX is a cluster or row of hairs above the mouth of insects (as various two-winged flies).
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