A new study indicates that the smallest living primate, Madame Berthe's mouse lemur (Microcebus berthae) might be extinct in the wild. Named after the late Malagasy primatologist Berthe Rakotosamimanana, no members of this species have been seen in the Menabe Antimena Protected Area (APMA) since 2018. The APMA was the forest with the largest population of these mouse lemurs, but despite its protected status, about 30% of the forest has been cut down for agriculture. It is possible that some members of the species still survive in the forest and in other areas of Madagascar outside of the APMA. But if the species has actually gone extinct, it would mark the first primate extinction in the 21st century. Of the 107 lemur species, 33 are considered "critically endangered" by the IUCN, meaning they are dangerously close to being extinct in the wild.
https://www.rfi.fr/en/africa/20220917-fears-world-s-smallest-primate-may-have-quietly-gone-extinct-berthe-lemur-madagascar
Original study:
https://conbio.onlinelibrary.wiley.com/doi/10.1111/csp2.12776