The translucent white body reveals few internal organs as most are also translucent white. There is an internal, large, black eye within the posteromesial base of each tentacle. The penis is a short muscular papilla within a stout, curving, preputium (muscular sheath) which, because it is opaque white, is sometimes visible (1) through the translucent white body. The preputium opens to the exterior at a small male genital pore (2) behind the right tentacle. For mating, the whole length of the preputium is everted by hydrostatic pressure of haemolymph, though only the small penis enters the partner (Morton, 1955). After mating, the preputium and penis are inverted back into the body by a retractor muscle.
The contents may be visible of the intestine/rectum (3) crossing the rear of the roof of the mantle cavity on its way to the anus in the adapical angle of the aperture.
Shell height 3.2 mm. With terrestrial invertebrates under stone embedded in soil just above EHWS. Menai Strait, Wales. September 2011.

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