i found this Noisette from another forum asking the same question-
We buy maigre a lot it tends to be quite cheap.. It's releated to "drums" which (I understand) are fished in
quantity off the African coast. This species occurs and is fished in the bay of Biscay. Small specimens have a
texture and taste a lot like bass, but the larger ones tend to flake and are better poached. It is a poor traveller
and deteriorates very quickly. Neither does it freeze well. These are reasons that it is seldom seen much away
from the Biscay coast.
hth
Anna x