Species of Syringophilopsis quill mites are found in the flight feathers of passerine birds. A phylogeny of species from this genus infecting North American passerines was inferred from the mitochondrial cytochrome oxidase I gene and the nuclear 28S ribosomal RNA gene. Based on the large genetic distance among lineages, the genus appears to be composed of several cryptic species. A reconciliation analysis of these mites and their avian hosts indicates a limited, but significant, degree of cophylogeny. However, strict cospeciation is not found to be occurring in this system.