This group is not representative of the species which lives in the bay of Quiberon, as it is not dredged in its classic habitat (sand, mud, offshore). The specimens collected here are an additional material which is fished together with the main target, Crassostrea gigas, by depths ranging from 10 to 20m. An other species, Mimachlamys varia, is also well represented in the catches. The collected Aequipecten opercularis are juvenile, still attached by their byssus.

The whole lot has the same pattern, with a maroon to dark brown background,
and white blotches which tend to disappear in adult specimens (see pop-up picture).
It could be that the species diversifies into growing old, but it is not possible to have confirmation of this.
It should be known that the fishermen bring to the market only a small handle of Aequipecten opercularis, mixed to much more M. varia (ratio: 1/20).

This standardization of the ornamentation could be related to some environmental constraints (predation, food), and it is not uninteresting to notice that the young Mimachlamys varia, which are not covered yet with algae, present the same patterns in the same colors.

To illustrate this matter, I did not have to excavate much in my bags.
I had only to take to pieces randomly, the first in the young A. opercularis, and the second in the naturally cleaned M. varia. Adult varia can considerably differ, as the name suggests it.

This could be an interspecific color convergence.
If it is not the result of the chance, if it results from a tendancy to camouflage, we have here an image of the UW bottom, such as predators perceive it.
But the principal defence of these two scallops remains one or more species of sponges, which protect them from the attacks of starfishes (mutualism).