Porrhomma

Species identification relies on examination of copulatory organs (genitalia), particularly the male palp and female epigyne. Troglomorphic species display extreme eye reduction, leg elongation, and pale or depigmented coloration. Non-troglomorphic species require careful comparison of somatic and genitalic characters with related linyphiid genera.

Habitats range from surface environments to subterranean caves. Several species are troglobitic (obligate cave-dwellers), including P. ozrenense from caves in Bosnia and Herzegovina. Other species occupy leaf litter, soil, and moss in forested and montane regions.

Europe, Asia (Russia, Kazakhstan, China, Korea, Japan, Iran, Turkey, Pakistan, Mongolia), and North America (USA, Canada, Alaska, Greenland). The genus spans the Palearctic with disjunct Nearctic occurrences.

Constructs sheet webs typical of Linyphiidae. Troglomorphic species have been observed in deep cave zones, suggesting limited movement to surface environments.

Predatory component of cave and soil arthropod communities. The discovery of P. ozrenense prompted conservation recommendations to preserve cave biodiversity in the Dinarides.

• LepthyphantesBoth are Linyphiidae with overlapping distributions; distinguished by genitalic morphology and eye arrangement in troglomorphic species.
• CentromerusSimilar habitat preferences and body form; separation requires detailed examination of male palpal sclerites and female epigynal structure.

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• A new troglobitic species of the genus Porrhomma (Araneae: Linyphiidae) from Bosnia and Herzegovina with taxonomic remarks on its relative Porrhomma egeria Simon, 1884