Project R-1948

Phylogeny of symbiotic taxa within the Neodalyellida (Platyhelminthes, Rhabditophora, Rhabdocoela), including aspects of co-evolution and cryptic biodiversity. (Research)

Within the species-rich taxon Platyhelminthes, diversity is also reflected in the many different types of life histories that are found within the taxon. Apart from the obligatory parasitic Neodermata, several taxa (Temnocephalida, Umagillidae, Graffillidae, Pterastericolidae) are symbiotic. The latter three will form the subject of my postdoc-project. Since little is known about the phylogentic position of the Rhabdocoela, to which the above mentioned symbionts belong, and their internal relationships, I will collect molecular data to unravel these relationships. For this purpose both mitochondrial (16S rDNA) as well as nuclear (18 and 28S rDNA) genes will be used in different analyses (parsimony and Bayesian inference). Apart from this purely phylogenetic work, I will examine the occurence of co-evolution within the Pterastericolidae, for which both the relationships of the symbionts as well as those of the hosts will be studied. To realise these goals, it is uttermost important to collect as many species as possible and therefore it can be expected that many new and poorly known species will be encountered. These species will be described in detail using light-microscopy. Whenever there is a hint of cryptic biodiversity molecular techniques (based on COI, cyt b, ITS1, ITS2) will be used to complement the classical, descriptive taxonomy.

01 October 2009 - 30 September 2012