The Stygnopsidae are a small family of harvestmen, with almost all species found in Mexico.
Name
The name of the type genus Stygnopsis is combined from the genus Stygnus (Stygnidae) and Ancient Greekopsis, "looks like".
Description
The body length of these harvestmen ranges from 2.5 (Karos) to 7mm (Hoplobunus). Their color ranges from dark brown to black, with much lighter appendages. Cave-dwelling species are pale light brown.
Distribution
As in other Laniatores, most species have narrow distributions. Almost all species occur in Mexico, with some found in the southern USA (Hoplobunus), and Guatemala, El Salvador and Belize (Paramitraceras).
Relationships
Epedanidae
Assamiidae
Stygnopsidae
other Gonyleptoidea
Proposed phylogeny (after Kury 2003)
Epedanidae could be the sister group to Gonyleptoideasensu lato (including the Assamiidae), with the Stygnopsidae the sister group to the rest of Gonyleptoidea. Although they reach into the Nearctic, they are more closely related to neotropical harvestmen.
Kury, Adriano B. (2003): Annotated catalogue of the Laniatores of the New World (Arachnida, Opiliones). Revista Ibérica de Aracnología vol. especial monográfico 1: 1-337.
Pinto-da-Rocha, R., Machado, G. & Giribet, G. (eds.) (2007): Harvestmen - The Biology of Opiliones. Harvard University PressISBN0-674-02343-9