04 Bittium reticulatum. Shell height 6.2 mm. Llŷn Peninsula, North Wales. March 2016.

04 Bittium reticulatum. Shell height  6.2 mm. Llŷn Peninsula, North Wales. March 2016.

Ground colour of body translucent white, heavily mottled with black/burnt umber and a little opaque white, combining with visible, internal, fawn-brown viscera to give an over all brown appearance to head and body. Pigmentation on dorsum continues to posterior of tentacles on parts likely to be exposed to view, but ceases further back into shell (1).
No penis on males; possibly because would obstruct respiration in such a small aperture.

marinvert.senckenberg.science/image-browse/