Microscopic-identification
Guides
Hahnia
comb-tailed spiders, dwarf sheet spiders
Hahnia is the most species-rich genus of the comb-tailed spider family Hahniidae, with approximately 102 valid species distributed worldwide. These spiders are small, cryptic arachnids characterized by their distinctive spinneret arrangement. Most species are under 4 mm in body length as adults. The genus was established by C. L. Koch in 1841 and was formerly classified within Agelenidae until recognized as a distinct family. Species occur across diverse habitats including caves, forest litter, and under bark.
Ptenothrix maculosa
Ptenothrix maculosa is a globular springtail in the family Dicyrtomidae, native to the temperate west coast of North America from Alaska to California. First described by Swedish entomologist Henrik Schött in 1891, this species exhibits extreme color polymorphism, leading to decades of misidentification and the synonymization of several conjectured undescribed species. Definitive identification requires microscopic examination of setal arrangements on the abdomen and furca. It serves as a decomposer in woodland ecosystems and has become a focal species for citizen science monitoring through photo-based identification.