Summary details for Evansia merens O.P.-Cambridge, 1900

Species Details

Species name: Evansia merens O.P.-Cambridge, 1900
Taxonomy: Animalia :: Araneae :: Linyphiidae

Distribution

An inhabitant of north and west Britain, it is rarely found south and east of the line connecting the Humber and the Exe, though a record from Berkshire in 2003 extended its known range by some 100 km. This species has a wide Palaearctic distribution and is fairly widespread in north-western and central Europe, but has not been recorded from Belgium or the Netherlands.

Habitat and ecology

Open heaths and moorland. This myrmecophilous spider has been recorded from the nests of several ant species (Lasius niger, L. fuliginosus, Formica fusca, F. sanguinea). It occurs exclusively in dry peaty soils. In these habitats it is usually found within ant galleries beneath large rocks or logs. Both sexes are mature throughout the year, with egg-sacs (affixed to rocks within the ant galleries) produced between May and August. Our data show a peak of recorded females in May.

Status

Populations appear to be increasingly fragmented. Recorded from 24 hectads since 1992, but showing a decline of 58% in Area of Occupancy (from 45 to 19 hectads) from before that date, though the species' specialised habitat may have resulted in some under-recording.

Threats

Destruction of heathland associated with urban and agricultural development pose threats.

Management and conservation

Protect heathland from urban and agricultural development. Text based on Dawson, I.K., Harvey, P.R., Merrett, P. & Russell-Smith, A.R. (in prep.).

Stats

First recorded: 1900
Last recorded: 2023
Total records: 204
Total visits: 201

Conservation status

Evansia merens

Source	Reporting category	Designation	Date designated	Comments
A Review of the scarce and threatened spiders (Araneae) of Great Britain: Species Status No. 22 (Sep 2017)	Rare and scarce species	Nationally Scarce. Includes Red Listed taxa	01/09/2017
A Review of the scarce and threatened spiders (Araneae) of Great Britain: Species Status No. 22 (Sep 2017)	Red listing based on 2001 IUCN guidelines	Least concern	01/09/2017	Threats: Destruction of heathland associated with urban and agricultural development pose threats.

Photos and media

Spatial distribution - hectad map

Click on one of the date ranges in the key to highlight that particular range. Click anywhere else on the map to go back to all three date ranges.

Thresholds:

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Rejected records are excluded from this map. Unverified records are included.

Temporal distribution - records by year

Records that span more than one year are not included in this chart.