The Opiliones are an order of arachnids colloquially known as harvestmen, harvesters, harvest spiders, or daddy longlegs. As of April 2017, over 6,650 species of harvestmen have been discovered worldwide, although the total number of extant species may exceed 10,000. The order Opiliones includes five suborders: Cyphophthalmi, Eupnoi, Dyspnoi, Laniatores, and Tetrophthalmi, which were named in 2014.
Cosmetidae is a family of harvestmen in the suborder Laniatores. With over 700 species, it is one of the largest families in Opiliones. They are endemic of the New World with a Nearctic-Neotropical distribution where a large fraction of the diversity of Opiliones are represented by this single family. Cosmetidae have the northern extent of their range into the USA, where a small number species occur in the southern states. However, the family is especially diverse in Mexico, Central America and northern South America; especially the Andean realms. Their range also extends further south into Argentina and southern Brazil, but they are absent in Chile. Cosmetidae are prevalent in Amazonian region, but only relatively few also occur in Brazilian Atlantic Forest. Several species are also found in the Caribbean.
The Phalangodidae are a family of harvestmen with about 30 genera and more than 100 described species, distributed in the Holarctic region.
Ischyropsalididae is a family of harvestmen with 35 described species in 3 genera, found in Europe and North America.
The Cranaidae are a family of neotropical harvestmen within the suborder Laniatores.
Kimulidae is a small neotropical family of the harvestman infraorder Grassatores with about thirty described species.
The Cladonychiidae are a small family of harvestman with about 33 described species, within the suborder Laniatores.
Taracus is a genus of harvestman, or Opiliones, typically found living in limestone and lava caves in the United States. They grow to a size of 2.0–5.5 mm (0.08–0.22 in).
Taracidae is a family of harvestmen in the order Opiliones. There are 4 genera and 23 described species in Taracidae.
Vonones is a genus of armoured harvestmen in the family Cosmetidae. There are at least two described species in Vonones.
Stygnomma is a genus of armoured harvestmen in the family Stygnommatidae. There are more than 30 described species in Stygnomma.
Taito is a genus of harvestmen in the family Cosmetidae. The genus is endemic to the Amazon Basin in Brazil, Colombia, Ecuador and Peru.
Rhaucus is a genus of harvestmen in the family Cosmetidae. The genus is endemic to the Colombian northern Andes. There are currently seven described species in the genus.
Poecilaemula eutypa is a species of harvestmen from Central America in the family Cosmetidae. It was first described by Ralph Vary Chamberlin in 1925.
Discosomaticinae is a subfamily of harvestmen in the family Cosmetidae.
Metergininae is a subfamily of harvestmen in the family Cosmetidae.
Poecilaemula iching is a species of harvestmen from Central America in the family Cosmetidae. It was first described by Medrano, Kury, Martins & Proud, 2024 in 2024.
Poecilaemula signata is a species of harvestmen from Central America in the family Cosmetidae. It was first described by Banks in 1909.
Abria is a genus of harvestmen in the family Cosmetidae with three described species. All species are from Venezuela. An overview of the taxonomy was provided by Villarreal, Medrano & Kury (2023)
