Callobius claustrarius

Callobius claustrarius is a species of spider in the family Amaurobiidae. Males of the species reach 8 mm, females about 11 mm. Head and legs are reddish brown, the abdomen is dark grey with an extended brown surface, dotted with lighter brown specks.

Callobius claustrarius
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Araneomorphae
Family:	Amaurobiidae
Genus:	Callobius
Species:	C. claustrarius
Binomial name
Callobius claustrarius (Hahn, 1833)
Synonyms
Clubiona claustrarius Amaurobius claustrarius Cybaeus tetricus Ciniflo claustrarius

Adults can be found from autumn to spring.

This is a palearctic species. In Europe, it is found in mountainous regions, especially in old, moist forests under rocks. C. claustrarius is a rather rare species.

The subspecies C. claustrarius balcanicus (Drensky, 1940) is only found in Bulgaria.^[1]