Comparative morphometric study of the invasive pearl oyster Pinctada radiata along the Tunisian coastline

Biologia (Impact Factor: 0.51). 04/2010; 65(2):294-300. DOI: 10.2478/s11756-010-0023-9

ABSTRACT In order to study the relative growth of the pearl oyster Pinctada radiata in Tunisia, a total of 330 individuals of this species were collected from six sites along the Tunisian coastline. Quantitative
measurements of collected oysters were conducted for shell height, shell length, shell width, hinge length, height and width
of the nacreous part and wet weight. The size structure of the sampled populations was described and the relative growth between
different morphometric characteristics was estimated as allometric growth lines for the six P. radiata samples. It appeared that the majority of examined samples were dominated by large individuals that exceed a shell height
of 42 mm. The maximum size (100.5 mm), recorded in Bizerta lagoon, is bigger than that recorded elsewhere in particular in
the Red Sea. Size distribution analysis also showed that the majority of P. radiata samples were dominated by two or more size groups. Differences of allometric regression were found between the examined samples
for the tested relationships. Moreover, the Factorial Discriminant Analysis, coupled with Ascending Hierarchic Classification,
classified the sub-populations according to geographic locations.

Key wordsmorphometry-pearl oyster-
Pinctada radiata
-Tunisian coastline

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