Are Shell Strength Phenotypic Traits in Mussels Associated with Species Alone?



Carboni S, Evans S, Tanner KE, Davie A, Bekaert M & Fitzer SC (2021) Are Shell Strength Phenotypic Traits in Mussels Associated with Species Alone?. Aquaculture Journal, 1 (1), pp. 3-13.

Mussels often hybridise to form the Mytilus species complex comprised of M. edulis and M. galloprovincialis as the main species cultivated in Europe and, where their geographical distribution overlaps, the species M. trossulus. It has been suggested that M. trossulus have a weaker shell than the UK native M. edulis and hybridisation reduces farmed mussel yields and overall fitness. Here, we investigate the hypothesised link between species and shell weakness, employing multi-locus genotyping combined with measurements of six different phenotypes indicative of shell strength (shell thickness, flexural strength, Young’s modulus, Vicker’s hardness, fracture toughness, calcite and aragonite crystallographic orientation). Historic evidence from shell strength studies assumed species designation based on geographical origin, single locus DNA marker or allozyme genetic techniques that are limited in their ability to discern hybrid individuals. Single nucleotide polymorphic markers have now been developed with the ability to better distinguish between the species of the complex and their hybrids. Our study indicates that shell strength phenotypic traits are less associated with species than previously thought. The application of techniques outlined in this study challenges the historic influence of M. trossulus hybridisation on mussel yields and opens up potential for the environment to determine mussel shell fitness.

Mytilus species complex; biominerals; aquaculture; material properties

Aquaculture Journal: Volume 1, Issue 1

FundersNERC Natural Environment Research Council and Scottish Aquaculture Innovation Centre
Publication date30/09/2021
Publication date online23/07/2021
Date accepted by journal16/07/2021
PublisherMDPI AG

People (3)


Dr Michaël Bekaert
Dr Michaël Bekaert

Senior Lecturer, Institute of Aquaculture

Dr Stefano Carboni
Dr Stefano Carboni

Aquatic Invertebrate Zoologist, Institute of Aquaculture

Dr Susan Fitzer
Dr Susan Fitzer

Lecturer, Institute of Aquaculture

Projects (1)