Ventral view of head valve of dried specimen. Animal length c.15mm. Littoral. Orkney, Scotland. 1974.
Insertion plates on the anterior edge of the head valve with 10 slits separating them (range 7 to 12 slits). On the ventral articulatum of valve i a diagonal slit ray with aesthete macropores runs from each slit.
The head valve (i) is the only one that lacks apophyses as there is no valve to its anterior to attach to.

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