Catalog and bibliography of the nonindigenous nonmarine snails and slugs of the Hawaiian Islands
The impacts of alien species are one of the major threats faced by many ecosystems, especially those of islands (Cowie, 1992d). The Hawaiian Islands are no exception. In order to evaluate potential impacts and to develop control measures or management practices to deal with alien species, a basic understanding of their biology is necessary. A prerequisite to this is knowledge of the identities of the species that have invaded the region of concern. To address this need for the non-marine snails and slugs introduced to the Hawaiian Islands, this catalog lists all the species that have been recorded as aliens in the wild in the Hawaiian Islands (22 freshwater and 63 terrestrial species). It complements the recently published catalog of the native species (Cowie et al., 1995a). The two works together constitute a complete listing of the recorded land and freshwater snail fauna of the archipelago. Many of the species are included in a list of type material in the Museum of Comparative Zoology, Harvard University (Johnson, 1996). The catalog lists all valid species-group names but also includes synonyms and nomenclaturally unavailable names if these have been used in reference to Hawaiian records; extralimital synonyms and unavailable names are excluded. Obvious incorrect subsequent spellings are not listed but may be mentioned in annotations, for clarity. Most records are derived from the literature, including unpublished reports, manuscripts, etc., but a small number are based solely on labels associated with material housed in the Bishop Museum collections. Only those species that appear to have been released or to have escaped into the wild (whether they have subsequently become established or not) are listed. Other species that have been deliberately brought to Hawaii (e.g., for biological control programs) but never released (e.g., Davis & Butler, 1964; Krauss, 1964), and species that have been brought to Hawaii either accidentally or deliberately but have been intercepted by quarantine officials, are excluded.
