Addendum Clarifies Taxonomy in MPXV Transmission Study from Squirrels to Mangabeys
A recent addendum to a Nature paper addresses a taxonomic revision concerning the fire-footed rope squirrel, crucial for understanding MPXV transmission dynamics.
Published on June 24, 2026, an addendum to a significant Nature paper, originally released on February 11, 2026, brings to light an important taxonomic clarification regarding the species involved in the transmission of the Monkeypox virus (MPXV). The initial research, conducted by Carme Riutord-Fe, Jasmin Schlotterbeck, Fabian H. Leendertz, and their extensive team, definitively identified the transmission of MPXV from fire-footed rope squirrels to sooty mangabeys. This groundbreaking study offered critical insights into the zoonotic origins and potential pathways of viral spread, focusing on the *Funisciurus pyrropus* species as the primary squirrel reservoir.
The necessity for this addendum arose from a subsequent study, published in One Health in 2025 by Curaudeau, M. et al., which proposed a significant taxonomic reclassification. This latter research suggested that West African populations of the fire-footed rope squirrel, previously considered part of a single species, should be elevated to a separate species under the new name *Funisciurus leucostigma*. Such revisions are not uncommon in zoological research, as advanced genetic analysis often reveals cryptic species or distinct populations warranting specific classification, especially when geographical barriers like the Sanaga River in Cameroon are identified as dividers.
In response to this new evidence, the authors of the original Nature paper, including Riutord-Fe, Schlotterbeck, and Leendertz, have formally agreed with the proposed taxonomic update. They confirm that their own mitogenomic phylogeny—a powerful tool for evolutionary analysis based on mitochondrial DNA—conclusively places the specific fire-footed rope squirrels investigated in their study within this newly designated taxon, *F. leucostigma*. This agreement underscores a commitment to scientific accuracy and the dynamic nature of biological classification, which evolves with new data.
It is important to note the timing of these scientific publications. The original Nature article, published in February 2026, adhered to the then-predominant nomenclature, using *F. pyrropus* to refer to all populations of the fire-footed rope squirrel. The authors explicitly stated in their addendum that this decision was made because the taxonomic revision proposed by Curaudeau et al. (2025) had not yet been broadly adopted by major reference databases at the time of their original paper's publication. This practice highlights the cautious approach of scientific journals and researchers in adopting new classifications until they gain wider acceptance within the scientific community.
The addendum, therefore, serves as a crucial update, ensuring that future research building upon their findings will operate with the most precise taxonomic understanding available. While the core finding of MPXV transmission from these squirrels to mangabeys remains robust, the identification of the squirrel host as *Funisciurus leucostigma* provides a more refined and accurate detail. This meticulous approach to species identification is paramount in ecological epidemiology, as subtle genetic or geographical distinctions between host populations can have profound implications for understanding disease dynamics, reservoir competence, and the development of targeted public health interventions. This addendum, published in Nature, exemplifies the rigorous self-correction and continuous refinement inherent in the scientific method.