Dicymbium nigrum/brevisetosum agg.

Separation of these species can only be based on males, with females being indistinguishable from each other. The genitalia of the two species are identical. The British Arachnological Society record these two as separate species with females being grouped together as Dicymbium nigrum/brevisetosum and males needing detailed microscopic examination before acceptance to species level. Identification is made more difficult as there are intermediate specimens, and by the fact that the two species may be able to interbreed as they have identical genitalia. Any records of females, or of males which have not been microscopically examined and shown to be conclusively of one species should be recorded to this aggregate page.  

• Prosoma (cephalothorax) 0.8-1.0 mm, inconspicuous, fovea clearly recognizable as a notch.
• Opisthosoma (abdomen) plain, unremarkable.  
• Tibial spines: 2-2-1-1.    
• Metatarsus IV with trichobothrium.  
• Front centre eyes significantly smaller than side eyes.
• Sternum rough, extended backwards.  

Confirmation of conclusive microscopic features required for positive identification. 

A common aeronaut which has been found in a wide variety of habitats including sphagnum bogs, grassland, damp woodland, heathland, marshes, wastelands and detritus.

Adults have been recorded throughout the year with peaks in early summer and autumn.

Common and widespread in Britain as an aggregate.

Status in Leicestershire and Rutland is not known, but it would seem that the species are under recorded in our area. 

http://srs.britishspiders.org.uk/portal.php/p/Summary/s/Dicymbium+nigrum