Current research topics
At the moment I'm a free-time researcher and as a consequence I have to make the most of my limited time. Nevertheless, there are several topics that interest me very much and keep me busy. Most of these are done in co-operation with other biologists.
Speciation in the Guayana Highlands
This work is being done in co-operation with Valentí Rull (Universidad de Barcelona) and Mónica Vera (Instituto de Ciencias Naturales, Bogotá). The basis is a hypothesis formulated by Rull and the model species are Plekocheilus snails. (Details)
Bulimulid species from northern Peru
Interesting material has been collected recently by Jens Hemmen and may clarify some issues on several genera, like the relations between Neopetraeus, Llaucanianus and Drymaeus. There is co-operation with Bernhard Hausdorf (Universität Hamburg).
Re-evaluation of the phylogeny of the Orthalicoidea
Since 1979, when I published a revision of the group, no comprehensive re-evaluation has been made. Modern techniques, like DNA sequencing, greatly enhace our insight in the phylogenetic relationships, which at that time could only be hypothesized. Several interesting topics have occurred, like the placement of Prestonella from South Africa in the group, that justify to take a fresh view using up-to-date methods. (Details) For this I also co-operate with Bernhard Hausdorf.
Terrestrial Mollusca from northern South America
This is a co-operative project with Francisco Borrero (Cincinatti Museum of Natural History) to make a catalogue of non-marine Mollusca, starting with an initial list of species from Colombia made by him, which we use as a starting point for further improvement and expansion to other countries in northern South America. The old name for this area is ‘New Grenada’ (hence the tab name), comprising Colombia, Ecuador, and parts of Venezuela and Panama. (Details)
Types of the Orthalicoidea
Types are the fundament of the classification building and it is important to know where type material is being kept and to have accurate data of these types. This project aims to revise museum collections and to (re-)publish types of Orthalicoidea, both from described and undescribed taxa. This is a project in co-operation with Eike Neubert (Senckenberg Natur-Museum) and others. (Details)
My current interests may be summarized by this figure:
