Ecology, distribution and species diversity of caddisflies (Trichoptera) in Flanders

Fresh watercourses are highly diverse ecosystems and the composition of the macroinvertebrate communities present in these different surface waters depends on the prevailing biotic and abiotic conditions that characterize the given location. Studies investigating the true biodiversity of freshwater invertebrates and their relationship with environmental factors though are scarce.

This research project investigates these ecological relationships as well as the phylogeny for the caddisflies (Cl. Insecta; O. Trichoptera) occurring in running freshwater systems in Flanders. The phylogenetic relationships are investigated utilizing a combination of morphological characteristics and genetic markers and the variance displayed in their nucleotide sequences. The research will contribute to an enhanced understanding of the taxonomy, phylogeny and ecology of the Flemish Trichoptera and the obtained molecular database will be used to develop a biodiversity-chip to identify these macroinvertebrates based on their genetic material. The project is thus a case-study in which we investigate (1) the possibilities offered by a molecular approach to conduct large-scale biodiversity research at the species level, and (2) which and how much additional information can be gained from using this approach.

The objectives of the research project are:
- to link accurate species identifications based on morphological characteristics to species specific gene sequences (DNA barcoding);
- to investigate the phylogenetic and phylogeographic relationships of the caddisfly species present in Flemish freshwater systems;
- to examine which genetic markers are best suited for the estimation of within-species variation and which markers are more suitable to analyse the relationships at a higher taxonomic level;
- to investigate whether the variability of intraspecies genetic variation and species composition can reflect differences in origin and historical background between locations at a larger geographical scale;
- to explore the possibility to use the developed DNA barcoding database for ecological research;
- to produce a biodiversity-chip – a DNA microarray capable of automatically determining the species composition of additional field samples.