We've decided that it's no longer necessary to keep the cylindricus group as all of the species that were not part of it have been moved to other genera. Even originally created it back when Ocyptamus was polyphyletic as a way to accommodate the species of Ocyptamus sensu stricto, but now Ocyptamus, as defined on iNaturalist, is equivalent. When Even split Ocyptamus on BugGuide he neglected to merge the cylindricus group back into the genus. (BugGuide has been fully updated.)
Mengual, X., Miranda, G.F.G. & Thompson, F.C. (2018) Unraveling Ocyptamus and the Baccha legacy (Diptera: Syrphidae): redefinition of groups and new species descriptions. Zootaxa, 4461 (1), 1–44. (Σύνδεσμος)
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.
