Prostoma jenningsi is a species of ribbon worm known only from one site near Croston, Lancashire.

The only site where P. jenningsi has been found is a former clay pit now used for recreational fishing between Bretherton and Croston in Chorley borough, Lancashire.

[3] Prior to the discovery of P. jenningsi, there had only been four reports of freshwater nemerteans in the British Isles, in the River Cherwell at Oxford, the River Cam at Cambridge, a tank in Regent's Park, London, and the Grand Canal at Clondalkin, County Dublin.

B. Jennings of the University of Leeds, a scientist who studied invertebrate digestive physiology.

[5] Prostoma jenningsi lives among the vegetation at the edges of the pond, including plant species Juncus effusus, Elodea canadensis, Myriophyllum spicatum, Phragmites communis, Potamogeton natans and Typha latifolia.