Sigmoria

Sigmoria species can be distinguished from other xystodesmid genera by characters of the gonopods (male reproductive appendages), which are the primary diagnostic features used in species-level taxonomy. As flat-backed millipedes, they exhibit the characteristic broad, flattened paranota (lateral extensions of body segments) typical of Polydesmida. Specific identification to species requires examination of gonopod morphology and often geographic location, given the narrow ranges of many species.

Eastern United States, with species occupying forested habitats. Many species have narrow geographic distributions, often restricted to specific mountain ranges or physiographic regions.

Eastern United States. Species are documented from the Appalachian region and surrounding areas, with many exhibiting highly localized distributions.

As detritivores, Sigmoria species contribute to decomposition and nutrient cycling in forest ecosystems. They process decaying plant material, returning organic matter to the soil.

Sigmoria species, like many xystodesmids, are capable of producing hydrogen cyanide as a chemical defense when disturbed. This defensive secretion can be irritating to human skin and mucous membranes.

• ApheloriaAlso in tribe Apheloriini; distinguished by gonopod structure and often by coloration patterns
• BorariaAnother eastern North American xystodesmid genus; separated by gonopod morphology and geographic distribution
• PachydesmusOverlaps in eastern range; distinguished by gonopod characters and body proportions

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life