Summary details for Silometopus ambiguus (O.P.-Cambridge, 1905)

Species Details

Species name: Silometopus ambiguus (O.P.-Cambridge, 1905)
Synonym: Silometopus curtus sensu Bristowe, 1939 non Simon
Taxonomy: Animalia :: Araneae :: Linyphiidae

Distribution

S. ambiguus is widespread on the coasts of Britain, especially in the region from Suffolk and Essex to north Kent. A European species recorded from Ireland, France, Belgium, Denmark and Norway.

Habitat and ecology

A halobiont, being found on saltmarshes, tidal estuaries and sand-hills by the sea, in tidal litter and on mud. Adults of both sexes have been recorded from February to June and September to November, but females may occur throughout the year.

Status

Local, but the spider may be frequent in suitable habitat. Although Bristowe (1939) had drawn attention to the uncertainty over the identity of Silometopus curtus (Simon), records of this species and of S. ambiguus (O. P.- Cambridge) were confused until Locket & Millidge (1961) suggested that there was just a single, somewhat variable, species for which they believed the name S. curtus had priority. However it was later shown by Denis (1963) that Simon's original description of S. curtus applied to a Mediterranean species which is different from the more widespread northern European species, S. ambiguus.

Threats

Sea level rise may pose a future threat to saltmarsh habitats.

Management and conservation

Ensure survival of saltmarshes through managed realignment. Text based on Dawson, I.K., Harvey, P.R., Merrett, P. & Russell-Smith, A.R. (in prep.).

Stats

First recorded: 1895
Last recorded: 2025
Total records: 694
Total visits: 661

Conservation status

Silometopus ambiguus

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	42979
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	42979	Threats: Sea level rise may pose a future threat to saltmarsh habitats.

Photos and media

Spatial distribution - hectad map

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Thresholds:

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

Temporal distribution - records by year

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