In accord with AOS-NACC (Chesser et al. 2020b), change the scientific name of Cozumel Emerald from Chlorostilbon forficatus to Cynanthus forficatus (Stiles et al. 2017a, b), based on genetic evidence that the traditional genus Chlorostilbon is not monophyletic, and this species is embedded within Cynanthus (McGuire et al. 2014, Hernández-Baños et al. 2020).
Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, J. A. Gerbracht, D. Lepage, B. L. Sullivan, and C. L. Wood. 2021. The eBird/Clements checklist of Birds of the World: v2021. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ (Link)
Unintended disagreements occur when a parent (B) is
thinned by swapping a child (E) to another part of the
taxonomic tree, resulting in existing IDs of the parent being interpreted
as disagreements with existing IDs of the swapped child.
Identification
ID 2 of taxon E will be an unintended disagreement with ID 1 of taxon B after the taxon swap
If thinning a parent results in more than 10 unintended disagreements, you
should split the parent after swapping the child to replace existing IDs
of the parent (B) with IDs that don't disagree.
