Land snails and slugs of Sabah and Labuan (Malaysia)

The history of the present handbook goes back to the first years of this century. During the early days of the BOR/MOL collection (Mollusca collection of Universiti Malaysia Sabah), material of land snails appeared difficult to identify. Literature on Sabah snails was generally scarce, scattered over mainly 19th century publications, and covered only a part of the species present in the material.

To address this problem, the first author started a manuscript with a concise overview over the Sabah snail fauna, which would finally develop into this handbook. The first unpublished version started circulating among Sabah students of the snail fauna around 2002. It covered all snail families, but while some are shortly revised, others are no more than an uncritical list of species names. Unidentified species were listed with numbers (e.g. ‘Charopa sp. 2’), or with codes (‘Charopa sp. BO-02’), or Charopa with unpublished species names (‘Charopa infrastriata’, without a valid description following ICZN rules). A new, more extensive but still unpublished version of the manuscript appeared in 2006. The informal species names (i.e. nomina nuda) increasingly posed a problem because they were used in publications by students of the Bornean snail fauna. Also, the many shortcomings of the manuscript directly translated into misidentifications in those publications. This made the production and publication of the present, more carefully considered handbook a matter of urgency. Having said that, the authors in no way claim that this work is more than a step on the long road leading to a representative knowledge of the land snail fauna of Sabah.

The production of this handbook had the 2006 version of the unpublished manuscript as a starting point, together with the revision of key groups in Vermeulen et al. 2015, as well as revisions of various other groups, some up-to-date, others with a slight patina of time. Together, these provided enough of a framework to complete the present handbook within a limited period.