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Opilio parietinus (Degeer)
National status Common County status Essex Scarce
Frequency Ratio 1.4 Tetrad Percentage 0.7
Tetrad Frequency 2.2

Monad Frequency 1.7
Distribution
There are very few records and the
species appears to be rare despite its
association with urban areas. There may be a
decline in the county.
Habitat and Ecology
Hillyard & Sankey (1989) note that the
species is highly synanthropic and common
on walls, fences, buildings and even found
in the centre of London.
The few recent Essex records are from
urban areas but older records in north-east
Essex arc apparently from semi-natural
habitats at Colne Point, Fingringhoe Wick.
Great Holland Pits, High Grove and Walton
Naze where O. saxatilis is frequent.
Records, presumed to be adults, range from
May to October with most found in September.
Threats
The association with urban habitats would suggest the species is not threatened.
Opilio saxatilis (CL. Koch)
National status Common County status Essex Common
Frequency Ratio 2.0 Tetrad Percentage 5.8 Monad Frequency 18.2 Monad Frequency 15.4
Distribution
Widely distributed and often frequent
especially near the coast. It may be under-
recorded in the agricultural mid-west of the
county where it may occur on roadside
verges and along wood edges.
Habitat and Ecology
Associated with open dry habitats
including dunes, landslips, borrowdyke
edges and banks, grazing marsh grasslands,
grasslands on sand and chalk, acid
grassland/heath, lichen heath, old mineral
workings, wood edges and roadside verges.
Adults from July to December, peaking
in August and September.
Threats
Not threatened.
Essex Naturalist (New Series) 16 (1999)