Adults are small to medium-sized (2.5-9.0 mm) flies, relatively stout, usually dark coloured Nematocera with stout legs. They are associated with ancient woodland. Larvae are xylosaprophagous and live in the moist, rotting wood of stumps and fallen trees.
Most are considered endangered due to the vulnerability of their habitat.
There are 15 described species worldwide from New Zealand, North America, South America, Japan and Russia. The 3 species in Europe are suspected to be introductions. There is one know fossil species from the Jurassic.
Originally considered to be two separate families, the Synneuridae and the Canthyloscelidae. Haenni  placed the Synneuridae as the subfamily Synneurinae. A phylogenetic reclassification by Amorim  has reduced the Synneurinae into a synonymy of Canthyloscelinae.
- Genus Exiliscelis Hutson 1977
- E. californiensis Hutson, 1977
- Genus Hyperoscelis Hardy & Nagatomi 1960
- Genus Prohyperoscelis Kovalev 1985
- P. jurassicus Kovalev, 1985 (fossil)
- Genus Synneuron Lundström 1910
- Hutson A.M. (1977). "A revision of the families Synneuridae and Canthyloscelidae (Diptera).". Bulletin of the British Museum (Natural History) Entomology (London: British Museum (Natural History)) 35 (3): 67–100.
- Haenni J.-P. (1997). Family Canthyloscelidae. In Papp L. & Darvas B. (eds): Contributions to a Manual of Palaearctic Diptera. Nematocera and Lower Brachycera. Vol. 2. Budapest: Science Herald. pp. 273–279.
- Amorim D. de S. (2000). "A new phylogeny and phylogenetic classification for the Canthyloscelidae (Diptera: Psychodomorpha)". Canadian Journal of Zoology (Toronto: National Research Council Canada) 78 (6): 1067–1077. doi:10.1139/z00-010. ISSN 1480-3283.