Xysticus is a genus of ground crab spiders described by C. L. Koch in 1835, belonging to the order Araneae, family Thomisidae. The genus name is derived from the Ancient Greek root xyst, meaning "scraped, scraper".
Alopecosa is a spider genus in the family Lycosidae, with about 160 species. They have a largely Eurasian distribution, although some species are found in North Africa and North America.
Theridion is a genus of tangle-web spiders with almost 600 described species around the world. Notable species are the Hawaiian happy face spider (T. grallator), named for the iconic symbol on its abdomen, and T. nigroannulatum, one of few spider species that lives in social groups, attacking prey en masse to overwhelm them as a team.
Clubiona is a genus of sac spiders that was first described by Pierre André Latreille in 1804.
Pardosa is a large genus of wolf spiders, with more than 500 described species that are found in all regions of the world.
Walckenaeria is a genus of dwarf spiders that was first described by John Blackwall in 1833. It is a senior synonym of Paragonatium, as well as Wideria, Cornicularia, Prosopotheca, Tigellinus, and Trachynella.
Agyneta is a genus of dwarf spiders that was first described by J. E. Hull in 1911.
Micaria is a genus of ground spiders that was first described by Niklas Westring in 1851. They are 1.3 to 6.5 millimetres long.
Haplodrassus is a genus of ground spiders that was first described by R. V. Chamberlin in 1922. They range from 3 to 10 millimetres. H. signifer is the most widespread species, found across North America except for Alaska and northern Canada.
Centromerus is a genus of dwarf spiders that was first described by David B. Hirst in 1886.
Oreoneta is a genus of dwarf spiders that was first described by C. Chyzer & Władysław Kulczyński in 1894.
