is the management of culture systems, where the emphasis is now more on the use of legislation and control measures, particularly in Europe, North America, Australia and New Zealand (Chapter 10). This also pertains to the control of diseases in bivalves and to hygiene standards for shellfish and shellfish waters.
This volume does not focus solely on marine mussels in the genus Mytilus but also incorporates research on other commercially important marine genera such as Perna, Aulacomya and Choromytilus, as well as noncommercial genera such as Modiolus, Geukensia, Brachidontes and hydrothermal vent Bathymodiolus species. It therefore has a broader scope and content than The Mussel Mytilus and consequently should not be regarded as a second edition.
Chapter 1 covers the phylogeny and evolution of the Bivalvia and Mytilida. Chapter 2 provides a detailed description of external and internal anatomy. Chapter 3 describes global and local distribution patterns and the physical and biological factors influencing marine mussel distribution and abundance, with a section on climate change and the actual and potential impacts of global warming, ocean acidification and hypoxia on marine mussels. Chapter 4 covers factors influencing filter feeding, together with dietary components and assimilation efficiency, and presents new material on the impacts of mussels on marine ecosystems. Chapter 5 deals with reproduction, larval development and settlement, and has new sections on sperm–egg interaction, larval dispersal, connectivity, identification and abundance estimates. Chapter 6 covers methods of measuring growth, the mussel shell as a marine archive and exogenous and endogenous modulators of growth. The processes of circulation, respiration, excretion and osmoregulation are described in Chapter 7, while Chapter 8 covers types and levels of contaminants in the marine environment, contaminant absorption and assimilation, kinetic modelling, mussel monitoring programmes and biomarkers of pollution. Chapter 9 describes the application of genetic methods, population genetics, global breeding programmes and the relatively new area of bivalve genomics. The fundamentals of mussel aquaculture are dealt with in Chapter 10, focusing on a number of key mussel species for detailed treatment and the effects of mussel culture on the environment; it includes a section on facilitating sustainable aquaculture development. Chapter 11 deals with diseases and parasites, with a large amount of new information on diagnostic methods and the diverse defence mechanisms utilised by mussels. Finally, Chapter 12 looks at the role of mussels in disease transmission to humans, with sections on production and processing controls, regulation of monitoring and quality control, including the HACCP system.
Notes
1 1 Bayne, B.L. (ed.) (1976) Marine Mussels: Their Ecology and Physiology. Cambridge University Press, Cambridge.
2 2 Gosling, E.M. (ed.) (1992) The Mussel Mytilus: Ecology, Physiology, Genetics and Culture. Elsevier Science, Amsterdam.
3 3 Gosling, E. (2003) Bivalve Molluscs: Biology, Ecology and Culture. Blackwell Publishing, Oxford.
4 4 Gosling, E. (2015) Marine Bivalve Molluscs, 2nd edition. John Wiley & Sons, Chichester.
Acknowledgements
I benefited greatly from the assistance and knowledge of librarians at the Hardiman Library of the National University of Ireland, Galway.
A book like this is in many ways as good as its illustrations, and I thank those who provided figures: Philippe Archambault, Sara Barrento, Brian Beal, Guisla Boehs, Frank Alberto Ocaña Borrego, Craig Burton, Thomas Carefoot, Noèlia Carrasco, Antonio Checa, Siu Gin Cheung, John Costello, David Cowles, Jeff Davidson, Elizabeth Fly, Gael Force Fusion, Argyll, Scotland, UK, Laas Hiebenthal, Jade Irisarri, Jaafar Kefi, Anja Monika Landes, Ionan Marigomez, Katherine McFarland, Ivona Mladineo, Arthur Morris, Jorge Navarro, Sandra Noel, Jiří Novák, Aida Ovejero, Bernadette Pagoda, Peter Petraitis, David Polo, Guido Poppe, Chris Richardson, Mindy Richlen, Gianluca Sarà, Julia Sigwart, Tore Strohmeier, Tianli Sun, Cindy Lee Van Dover and David Wethey.
Thanks also to the team at John Wiley & Sons, Ltd: Sonali Melwani, Kerry Powell, Rebecca Ralf, Blesy Regulas, and, in particular, Sivasri Chandrasekaran, for their encouragement and feedback on the long course from commissioning to proofs.
Finally, and above all, I wish to thank my son, Marcus Gosling, who provided invaluable technical support and graphics expertise, and my partner, Jim, an exemplar of diligence and support.
1 Phylogeny and Evolution of Marine Mussels
Introduction
The phylum Mollusca is the second largest phylum of animals, with about 130 000 named extant species and 70 000 described fossil species (Haszprunar et al. 2008). While most of these are marine, many live in freshwater and terrestrial habitats. Research has indicated that molluscs had a terminal Precambrian origin, with rapid divergence occurring in the Cambrian era some 540–560 million years ago (Stöger et al. 2013). All molluscs have a soft body that, with the exception of some groups (see later), is protected by a hard calcium shell. Inside the shell is a heavy fold of tissue called the mantle that encloses the internal organs of the animal. Another feature of the phylum is a large muscular foot that is generally used for locomotion. Although most molluscs share this basic body plan, the group is characterised by a great diversity of form and habit.
Phylogeny of the Phylum Mollusca
Eight living classes (lineages) of molluscs have been recognised, primarily based on clad1 (phylogenetic) analysis of morphological characters (Haszprunar et al. 2008). Aplacopora incorporates two classes, Solenogastres and Caudofoveata; these are worm‐shaped, deep‐water animals lacking a shell. Polyplacophora, often referred to as chitons, inhabit hard substrates on rocky shores and are characterised by eight dorsal shell plates. Aplacophora and Polyplacophora are grouped in the clade2 Aculifera, which is regarded as monophyletic (i.e. all taxa in this group share a common ancestor) (Sigwart & Sutton 2007). The remaining five classes are grouped in the clade Conchifera, which is also regarded as a monophyletic group. Monoplacophora live in deep waters and are small and limpet‐like, with a single cap‐like shell. The class Bivalvia includes laterally compressed animals enclosed in two shell valves, such as clams mussels, oysters and scallops. Scaphopoda, commonly known as tusk shells, live in marine mud and sediments. The class Gastropoda is the largest and most diverse, containing spirally coiled snails, flat‐shelled limpets, shell‐less sea slugs and terrestrial snails and slugs. Octopus, squid and cuttlefish are in the class Cephalopoda and represent the largest, most organised and specialised of all the molluscs. The Monoplacophora are generally
