Uloboridae
Guides
Hyptiotes
Triangle Web Spiders, Triangle Spiders
Hyptiotes is a genus of small cribellate spiders in the family Uloboridae, commonly known as triangle web spiders. These arachnids are distinguished by their unique triangular webs—rudimentary orb webs consisting of four radii connected to a single anchor thread. They are notable as the only spiders in North America that lack venom glands, relying instead on specialized silk to capture and subdue prey. Adult females measure 3-4 mm, while males are 2-3 mm. Four species occur in North America, with three primarily western and one eastern species (H. cavatus).
Hyptiotes gertschi
Gertsch's Triangleweaver
Hyptiotes gertschi is a cribellate orb-weaving spider in the family Uloboridae, commonly known as Gertsch's Triangleweaver. Like other members of its genus, it constructs a distinctive triangular web—a reduced sector of a typical orb web. The species is one of four Hyptiotes species in North America and is distributed across the United States and Canada, with records from Alberta, British Columbia, and Manitoba.
Miagrammopes
Miagrammopes is a genus of cribellate orb-weaving spiders in the family Uloboridae, first described by O. Pickard-Cambridge in 1870. These spiders are distinguished by their reduced eye complement—retaining only four of the original eight eyes—and their highly modified web-building behavior. Rather than constructing traditional orb webs, they spin single horizontal threads with viscid capture silk, employing a unique hunting strategy of maintaining tension and releasing the line with a snap to entangle prey. The genus currently includes 71 recognized species and is distributed across tropical and subtropical regions.
Miagrammopes mexicanus
Miagrammopes mexicanus is a species of cribellate orb-weaving spider in the family Uloboridae. It was described by O. Pickard-Cambridge in 1893. The species is known from the United States and Mexico. Like other members of its genus, it possesses a cribellum—a silk-producing organ that generates extremely fine, dry silk used in prey capture.
Octonoba
Octonoba is a genus of cribellate orb-weaving spiders in the family Uloboridae, established in 1979. The genus comprises 33 described species distributed across East Asia, with highest diversity in China, Japan, and Taiwan. Members are characterized by a carapace length exceeding 1.4 mm, distinguishing them from the related genus Purumitra. One species, O. sinensis, has been introduced to the United States.
Octonoba sinensis
Octonoba sinensis is a cribellate orb-weaving spider in the family Uloboridae. Native to East Asia, it has been introduced to the United States. As a member of Uloboridae, it lacks venom glands and instead uses a cribellum—a specialized silk-producing organ—to create sticky capture threads.
Philoponella
Philoponella is a genus of uloborid spiders characterized by the absence of venom glands, a trait shared by all members of family Uloboridae. These spiders are obligate web-dwellers that capture prey using silk rather than venom. The genus exhibits notable behavioral diversity, including both solitary and social species, with some demonstrating cooperative prey capture. Philoponella species are primarily pantropical in distribution.
Philoponella arizonica
Philoponella arizonica is a species of crevice weaver spider in the family Uloboridae, first described by Gertsch in 1936. The species occurs in the southwestern United States and Mexico. Like other members of the genus Philoponella, it constructs characteristic sprawling, lacy cribellate webs that issue from retreats in crevices and sheltered locations. Females are notably long-lived and continue to molt after reaching sexual maturity, a trait shared only with mygalomorph spiders among arachnids.
Uloborus diversus
hackled orb-weaver, featherlegged orb-weaver
Uloborus diversus is a cribellate orb-weaving spider in the family Uloboridae. It inhabits desert regions of the southwestern United States and Mexico. The species is one of few North American spiders that lack venom glands, instead subduing prey through silk constriction. It has become an important model organism for studying the evolution of spidroins (spider silk proteins) and the neurobiology of orb-web construction behavior. A chromosome-level genome assembly has been completed to support this research.