Pirata hygrophilus

Males 4.5 to 5.5 mm, females 5 to 5.7 mm. Prosoma dark brown to black, with distinct bands of prosoma. Legs distinctly annulated (mainly femur). Opisthosoma with bright spots on both sides of median line.

Pirata piraticus

Confirmation 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.

In the ground layer of damp woodland, raised bogs, lowland heaths, marshy grassland and other damp or wet habitats, but not normally associated with open water.

Summer.

Widespread in the southern half of Britain. Less frequently recorded than P. piraticus, with which it often occurs, but may be locally abundant. It is possibly under-recorded because it is less active during the day and more likely to remain hidden under vegetation.

Under recorded in Leicestershire and Rutland.

http://srs.britishspiders.org.uk/portal.php/p/Summary/s/Pirata+hygrophilus