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.

Description

This family comprises members that may have elaborate white or yellow (but rarely also green/orange/red) markings such as stripes and spots on the dorsal body and peculiar pedipalps strongly compressed and applied on the chelicerae. Some aspects of diagnosis are as follows See more details in Kury & Pinto-da-Rocha (2007).

Etymology

The family name is derived from the type genus Cosmetus, which is from the Greek kosmetós 'ornate'.

Taxonomy

As of 2006, there are 125 genera and 712 species described. Most species belong to Cynorta (153 spp), Paecilaema (102 spp), Flirtea and Erginulus (30 spp each). However, there is no reason to believe most of genera of cosmetids are natural groups, except for a few like Metavononoides, Cosmetus (Kury, 2003) and Roquettea (Ferreira & Kury 2010). Attempts to organize the family in supra-specific units are hindered by the poorly resolved basic taxonomy. The family was divided into two subfamilies for many years as: Cosmetinae and Discosomaticinae.

Relationships

Cosmetidae is the sister-group of Gonyleptidae and both are closely related to the Stygnidae and Cranaidae (Kury, 1992). The family was subsequently divided into seven subfamilies as: Cosmetinae Koch, 1839 Cynortinae Mello-Leitão, 1933 Discosomaticinae Roewer, 1923 Ferkeriinae Medrano, Kury & Mendes, 2021 Flirteinae Medrano, Kury & Mendes, 2021 Libitiinae Medrano, Kury & Mendes, 2021 Metergininae Medrano, Kury & Mendes, 2021 Taitoinae Medrano, Kury & Mendes, 2021 Below is a scheme of genera now placed into revised subfamilies. Many currently recognised genera remain unplaced in subfamilies. The following genera are recognised, but unplaced in a subfamily: