Fauna Helvetica 2. Atlas der Mollusken der Schweiz und Liechtenstein

This impressive and important distribution mollusc atlas is the second volume in the Fauna Helvetica series, the first being a Diptera checklist. It is the result of a project launched on in 1981 although the bulk of record accumulation took place between 1988 and 1997. The basis of the work is 279 distribution maps using the 5x5 Km square as a mapping unit (four times as fine a grid as the Great Britain and Ireland scheme) to cover indigenous freshwater and land mollusc species, subspecies and segregates.

But there is much more to it than that. There are sections on the history of malaco- logical research in Switzerland, on the mapping project itself, on Switzerland as a molluscan habitat, together with a systematic list of Quaternary and Recent molluscs and other sections on temporary introductions and greenhouse aliens, uncertain records and species only recorded as Pleistocene and Postglacial fossils, a summary of the content and unresolved problems in four languages including English, a useful German, French, Italian, English vocabulary, a list of institutions and individuals holding mater- ial, a bibliography and indexes of French and German vernacular names and scientific names.

Each map is accompanied by text covering synonyms, global and Swiss and Liechtenstein distribution, altitudinal range, ecology and biology, and conservation "Red Listing" in respect of Switzerland, Bavaria, and Austria, and a black and white photograph (except for the slugs, illustrated in the colour plates). There are 67 excellent colour photographs of living land molluscs, plus 12 of shells (mainly umbilical views of Trichia species, but also Sphaerium corneum). Maps are not given for the temporary intro- ductions and greenhouse aliens, for the doubtfully recorded species, uncertain records, or for the Pleistocene and Postglacial fossils not found living in the area.

Records are distinguished on the maps mainly by date: 42000 for 1951-57, 13000 for 1901-1950, 11000 pre-1901, plus 1000 fossil records and 100 undated from literature. Given that the mapping unit is a 5x5 Km square, this enables production of a good picture of the areas in which a species is to be found even if it does not result in solidly filled-in maps for species which are virtually ubiquitous over much of the country, for example Aegopinella nitens.

The fauna of the area is very much controlled by the terrain and its underlying geology; many of the maps show this excellently; examples include Cochlostoma septem- spirale (Razoumousky, 1789)(p.71), Trichia montana (Studer, 1820) p. 342), Retinella hiuica (Albers, 1850) (p.268), and Oxychilus helveticus (Blum, 1881) (p.277). Ten species were added to the area's fauna as a result of the mapping project, and a further 12, previously poorly known there were better documented. Taxonomic treatment of species differs somewhat from that adopted in Kerney 1999' For instance Stagnicola species are mapped separately as Stagnicola corvus (Gmelin, 1791), S.fuscus (Pfeiffer, 1821) and Stagnicola sp indet. and Pupilla bigranata (Rossmassler, 1839) is kept separate from P muscorum (L., 1758). The systematic order used in the book is based on the results of a 1992 sympo- sium on the systematics and nomenclature of north and mid- European land and fresh- water molluscs organised by the Deutsche Malakozoologische Gesellschaft, and differs from that in Kerney 1999.

There are bound to be areas of taxonomic uncertainty and uneven mapping coverage in describing the malacofauna of this area and readers are carefully warned (in section 11) that much work remains on such area as the systematics and anatomy of Trichia species, and many of the slugs, and on the faunas of high altitude lakes. Looking at the maps on page 355 it is not clear whether the records for Helicella itala (L., 1758) and Xerolenta obvia (Menke, 1828) are based on dissection; their ranges appear to overlap except in the south east.

Readers familiar with the British and Irish distributions will encounter some interest- ing differences in relation to species we consider common here. For example, Lauria cylindracea (da Costa,! 778) is a rare species of west Switzerland; Vitrea contracts. (Westerlund, 1871) is much less common than V. crystallina (Muller 1774); there is only one literature and one pre-1951 record for Limacus flavus (L.,1758); Anon intermedius (Normand.1852) is recorded only from scattered localities in north Switzerland (inci- dentally the colour photograph on p. 442 looks like the juvenile of another Arion species, and lacks the typical upstanding tubercles), and Trichia striolata is only recorded from a small area in the north east of Switzerland.

Most but not all the sections of the book have the text in two columns for German and French, but in the copy seen by the reviewers the text accompanying the maps is in German/and so are the sections on temporary introductions and greenhouse aliens, the doubtfully recorded species, uncertain records, and on the Pleistocene and Postglacial fossils not found living in the area. Section 11, the summary of the contents and results which also deals with unresolved problems, is in German, French, Italian and English.

The book is very well produced, with a slightly loose hard-back binding which enables it to lie flat. Photographic and map quality is generally excellent though caution is called for in attempting to identify Pisidium species from the photographs alone. The price is reasonable for a work of this type.

It is very strongly recommended as a landmark source of information on the molluscan fauna of the area. The authors are to be congratulated for all their hard work and persistence in seeing through this work.

' KERNEY M.P. 1999 Atlas of the Land and Freshwater Molluscs of Britain and Ireland Harley Books.