Amphiporus rectangulus Strand, Herrera-Bachiller, Nygren & Kånneby, 2013

Length up to 1 cm, width 1 mm. Appearance sturdy and chubby. Body soft and movement calm. Body shape very variable, but tapering backwards. Dorsal side brownish, like nougat, with ventralside and lateral margins pale. Furrows pale, deep, and very obvious - encircling head meeting in rather steep V-shape dorsally . In some specimens, single pale stripe present, commencing behind V-shape as longitudinal pigmentation reaching backwards full or nearly full body length. Other specimens lacking this paler stripe; coloration obviously variable intra-specifically. No eyes distinguishable. Body wall quite thick, through which rhynchocoel and proboscis difficult to observe.