Corinnidae

The corinnid sac spiders of the family Corinnidae, like the other "clubionoid" families, have a very confusing taxonomic history. Once this family was a part of the large catch-all taxon "Clubionidae", now a shadow of its former self. The "clubionoids" are apparently similar only in that they have eight eyes arranged in two rows, conical anterior spinnerets that touch and are generally wandering predators that build silken retreats, or sacs, usually on plant terminals, between leaves, under bark or under rocks.

Among the families formerly classified as "Clubionidae", some of which have common names including the words "sac spider", include:

• Anyphaenidae (anyphaenid sac spider)
• Tengellidae (tengellid spider)
• Zorocratidae (zorocratid spider)
• Miturgidae (long-legged sac spider)
• Corinnidae (corinnid sac spider)
• Liocranidae (liocranid sac spider)
• Clubionidae (sac spiders)

The Corinnidae, as now recognized, contains 75 genera and over 900 species worldwide, making it the largest of the "clubionoid" families. Among the common genera are Castianeira (nearly world wide),Corinna (widespread), Meriola (New World), Phrurolithus (widespread), Phrurotimpus (North America) and Trachelas (widespread).

Members of the genus Castianeira appear to be mimics of ants and velvet ants. Other corinnid ant-like genera include Mazax, Myrmecium and Myrmecotypus. The "phurolithines" (including Phrurolithus and Phrurotimpus) are tiny spiders often found in leaf litter that have many ventral spines on their first tibiae. The 'trachelines" (Meriola and Trachelas) are usually bicolored spiders with red-brown cephalothoraxes (carapace) and dirty grey to yellowish abdomen. Corinna is the type genus for the family and consists of small running spiders.

• Platnick, N.I. 2003. World Spider Catalog