Heterobranchia 1: Marine gastropods 4
Marine gastropods 4 covers all the marine hetrobranchs, except the Sacoglossa and Nudibranchia. These molluscs include many sea hares and sea slugs.
In addition this volume includes a key to all families of shelled marine gastropods found around Britain and Ireland. This leads to additional keys to all British and Irish genera and species. Illustrated species accounts cover diagnostic characters, biology, distribution and range.
Heterobranchia is a large subclass of over 26,500 species worldwide, combining two previous subclasses (the Opisthobranchia and the Pulmonata) with a number of other species earlier regarded as caenogastropods. Currently there are 8471 marine species within the subclass. The remaining 18,000 or so species are either terrestrial or freshwater animals. But overall only a small subset of the worldwide fauna occurs in British and Irish waters.
Marine heterobranchs live in both the intertidal and sublittoral zones. They may burrow in soft substrata, graze Zostera beds or forage on boulder beaches and rocky shores. Although some species forage at the surface, it may be necessary to dig and sieve the sediments. Collection is best at low water on a good spring tide. For the smaller species, a useful technique is to pluck tufts of finer weeds low on the shore, then wash them into a dish. Many of these tiny gastropods may only emerge from material in the lab.
Synopses of the British Fauna is a series of identification guides. Each volume in the series is a detailed account of a group of animals. They bridge the gap between standard field guides and more specialised monograph or treatise. Since 1993 the the Field Studies Council has published these guides on behalf of the Linnean Society.
These volumes are suitable for the lab or field. The editors aim to keep them as user friendly as possible, with technical terminology at a minimum and a glossary of terms. However the complexity of the subject matter makes the books more suitable for the more experienced practitioner.