The serpent nest conjecture for accordion complexes

Consider 2n points on the unit circle and a reference dissection D∘ of the convex hull of the odd points. The accordion complex of D∘ is the simplicial complex of subsets of pairwise noncrossing diagonals with even endpoints that cross a connected set of diagonals of the dissection D∘. In particular, this complex is an associahedron when D∘ is a triangulation, and a Stokes complex when D∘ is a quadrangulation. We exhibit a bijection between the facets of the accordion complex of D∘ and some dual objects called the serpent nests of D∘. This confirms in particular a prediction of F. Chapoton (2016) in the case of Stokes complexes.