Willowsia nigromaculata

True Willowsia nigromaculata can be distinguished from the North American cryptic species Willowsia neonigromaculata by the number of inner appendages on the maxillary sublobal plate. It has interrupted rib scales, unlike some other Willowsia species such as W. mexicana and W. pyrrhopygia which have uninterrupted rib scales. Dorsal head chaetotaxy provides additional diagnostic characters for identification within the genus.

Metallic iridescent body covered in translucent scales. Morphological studies indicate it has interrupted rib scale type. Diagnostic characters include specific features of the maxillary sublobal plate, which distinguish it from the cryptic species Willowsia neonigromaculata.

Primarily found in indoor environments including houses, garages, and greenhouses. The species has been documented as a common household pest, suggesting adaptation to human-modified environments.

France (type locality of true W. nigromaculata); widely distributed throughout the northern hemisphere. Populations previously reported from the United States have been reclassified as the distinct species Willowsia neonigromaculata. Both species may be present in Canada. GBIF records indicate additional distribution in Arctic and Sub-arctic regions, Caribbean mainland, Continental Southeast Asia, Europe, and India.

Commonly reported as a household pest, indicating persistent presence in human dwellings. No specific behavioral details beyond habitat association have been documented.

Considered a household pest due to its common occurrence in houses, garages, and greenhouses. The species' widespread distribution in indoor environments suggests it may be transported internationally through human activity.

• Willowsia neonigromaculataCryptic species previously confused with W. nigromaculata; distinguished by number of inner appendages on maxillary sublobal plate; occurs in United States
• Willowsia mexicanaNew World endemic with uninterrupted rib scale type, unlike W. nigromaculata which has interrupted rib scales
• Willowsia pyrrhopygiaNew World endemic with uninterrupted rib scale type and distinct color pattern

Historically, specimens identified as W. nigromaculata from North America were misidentified; these represent a distinct cryptic species, Willowsia neonigromaculata. True W. nigromaculata is European in origin.

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Morphological and molecular analysis of Willowsia nigromaculata (Collembola, Entomobryidae, Entomobryinae) reveals a new cryptic species from the United States
• A new endemic species of Willowsia from Florida (USA) and descriptive notes on all New World Willowsia (Collembola: Entomobryidae)