Specimen preserved in alcohol from Orkney, Scotland. Insert of ctenidia X3. February 2015. Leg. P. Lightfoot per J. Porter.
Preservation has caused loss of colour, and the surround of the mouth contort into a hood, but it emphasises the 21 ctenidia (range 17 to 26) along either side of the foot. Both images are of the same specimen, but the angle of view makes the left one look almost holobranch (= ctenidia extend to anterior of foot) and the right one merobranch (= ctenidia fail to extend to anterior of foot)
1: mantle cavity.
2: ctenidia almost reach anterior of foot.
3: mantle fold.
4: mantle lappet.
5: lamellae of pinnate ctenidium.
6: surround of mouth contorted into hood.

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