1-Perna perna - african mussel -  15 cm in length

This very large species can tolerate a relatively high pollution, it lives in the same areas than the European mediterranean species Mytilus galloprovincialis, on any kind of hard bottoms  between  1 and  5 m depth.
It is relatively abundant near  Bizerte and in the area of Tunis harbour.

2-Eastonia rugosa- rugosa mactra-  85 mm in length
This large sea-shell  has a  high  pollution tolerance. It lives, in Tunisia,  only in the neighbourhood area of the Tunis harbour between 1 and 3 m depth , on the same sand -mud bottoms as the grooved carpet shell  Venerupis decussatus.

 II-Indo-pacific species living only in southern  Tunisia (from the  Kerkena islands to Zarzis ).

 3-Pinctada radiata -pintadina -  80 mm in length.
This species get into Mediterranean few years  after the construction of the Suez canal . It is present and very abundant  in the Gabès gulf from the beginning of the  20° century. But, today, we note his  constant regression due  the pollution in the gulf (strong eutrophication by  discharges in the sea of phosphate industry sewage).
However, it remains very abundant, principally around the Kerkena islands, on all kinds of hard bottoms between  0,5 and 5 m depth.

Photo 1: inner part of the shell of  a young specimen
Photo 2: old specimen
 
Photos by J. Zaouali