Dolichousnea was proposed as a new genus for Usnea longissima, but this is generally not accepted in the lichenological community. More specifically, Esslinger's (2018) North American Lichen Checklist does not accept Dolichousnea as a genus, and this is the authority used by iNat.
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.