The spider family Titanoecidae has a globally broad distribution and includes 53 described species, four of which occur in North America north of Mexico (Platnick 2014). All four of these North American representatives are in the genus Titanoeca, which is common and distributed across the contiguous United States (excluding peninsular Florida) north to Alaska and southeastern Canada. In the field, titanoecids resemble small to medium-sized amaurobiids, but Cutler (2005) notes that in North America a spider seen in a relatively xeric (arid) habitat near the ground is more likely to be a titanoecid than an amaurobiid.
Like most spiders, titanoecids have eight eyes. The thin cribellate sheet webs are usually built under rocks and often look faintly bluish (Bradley 2013). The egg sacs are globular and suspended in the web (Cutler 2005).
A key to the North American titanoecids was provided by Leech (1972), who treated titanoecids as comprising a subfamily (Titanoecinae) within the family Amaurobiidae.(Cutler 2005; Platnick 2014).
Titanoecidae is a family of araneomorph spiders first described by Pekka T. Lehtinen in 1967.[2] It is fairly widespread in the New World and Eurasia with five genera and more than 50 species worldwide. These are mostly dark-colored builders of "woolly" (cribellate) silk webs. Several species are found at relatively high altitudes in mountain ranges and may be very common in such habitats.
As of April 2019, the World Spider Catalog accepts the following genera:[1]
Titanoecidae is a family of araneomorph spiders first described by Pekka T. Lehtinen in 1967. It is fairly widespread in the New World and Eurasia with five genera and more than 50 species worldwide. These are mostly dark-colored builders of "woolly" (cribellate) silk webs. Several species are found at relatively high altitudes in mountain ranges and may be very common in such habitats.