Length 5 to 10 mm. Prosoma red-brown, dark. Legs reddish yellow, annulated. Opisthosoma dark, median with slender, arrow-shaped, yellowish longitudinal stripe, posteriorly 2 rows of yellow-greenish spots. 

Identification of this species "Requires examination at high magnification in good lighting, typically examination of the genitalia." Bee, L., Oxford, G., & Smith, H. (2020). Britain's Spiders: A Field Guide. Second Edition. Princeton University Press.

Near water, in moss and humid ground litter.

Summer

Widespread in Wales, scattered in England.

Uncommon in Leicestershire and Rutland.

https://srs.britishspiders.org.uk/portal.php/p/Summary/s/Arctosa+leopardus