Length 14.5 mm. North Yorkshire. September 2014. (leg. Paula Lightfoot).
1: hyponotum spread wide to grip substrate; paved with elongate oval, strongly ribbed, colourless scales (20X16μm to 44×18μm), often some stained brown.
2: mantle lappet (posterior expansion of mantle fold) partly concealing ctenidia.
3: hyponotum turned out to form channel at posterior for release of faecal pellets from adjacent anus, as well as exhalent water and sperm or ova.
4: foot spread widely to grip substrate; partly concealing pallial cavity.
5: posterior part of pericardium containing heart.
6: white articulamentum of tail valve (viii) visible through transparent tissue; narrow grey marks are muscle bundles attached to tail valve.

KEY ID FEATURES and similar species at: 01 Boreochiton ruber. Length 12mm. North Yorkshire. September 2014. (leg. Paula Lightfoot).