Partulid tree snails are little known, even to zoologists. If anyone has heard of them it is probably for their tragic recent history. Following the introduction of predatory snails in 1974 a third of partulid species are now extinct and almost all others threatened with extinction. However, before Partula became icons of extinction, they were central to the development of our understanding of evolutionary biology. This started with the pioneering field studies of evolution by Henry Crampton in 1908 which, in turn, led on to the development of genetics as a scientific field.

Crampton intended to unravel the process of speciation and inheritance in a series of monographs covering all Partula species but his great work was unfinished by the time of his death. ‘Icons of Evolution’ marks the centenary of the publication of Crampton’s first volume by completing his work, and updates it with a full revision of the taxonomy, and comprehensive accounts of what is known of the history, ecology, evolution and conservation of the family. This revision consolidates the 344 names applied to the family into 103 species, including the description of 5 new species. Each valid species is described with full references and synonyms, distribution maps, and photographs of 842 shells: type specimens of each species and all colour varieties. This is based on measurements of 125,824 shells, dissections of 1,244 snails and the analysis of 30 years of data from the captive breeding programme. Available from Phelsuma Press or Amazon .