Phylogenetic analysis and evoluntionary morphology of selected organ systems of Araneae (spiders) with focus on basal Araneomorphae and Haplogynae

• Antragsteller: Professor Peter Michalik, Ph.D.; Privatdozent Dr. Christian S. Wirkner
• Fachliche Zuordnung: Systematik und Morphologie der Tiere
• Förderung: Förderung von 2011 bis 2015
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 190786360

The project represents the first comprehensive analysis of two major organ systems within Araneae, the circulatory system and the male genital system, with a special focus on the basal Araneomorphae and the highly diverse Haplogynae. Aiming to contribute to the phylogeny and the evolutionary morphology of these spiders, three major steps are necessary:1.) Structural analyses will be performed on 30 spider species to represent the group’s morphological diversity. To analyze the structure of the circulatory organs a combination of micro-computer-tomography and histological methods will be applied. For the male genital system ultrastructural and histological techniques will be used. Data from both organ systems will be visualized using modern 3D reconstruction and virtual reality methods allowing for a more objective interpretation of the data. 2.) Compilation of a morphological data matrix by combining data from the two organ systems with other published data. To avoid a phylogenetic bias, we aim to analyze the morphological data alongside with available molecular data. To obtain robust phylogenetic hypotheses, different data congruence tests and possibilities of data combinations will be explored. This will in turn allow for the evaluation of the position of controversially discussed taxa such as Filistatidae and Austrochilidae.3.) In the last step the sequential order of character transformations will be traced on phylogenetic hypotheses, in order to elucidate the evolution of the two systems within spiders and to evaluate possible correlation between different organ system as e.g. respiratory system and circulatory system (see also hypotheses). Major aim will be the reconstruction of the ground patterns for both organ systems within araneomorph spiders.Therefore, this multi-methodological approach not only aims to generate a branching pattern, i.e. phylogeny of investigated spiders, but also tries to reconstruct the structural evolution of the circulatory system and the male genital system in those taxa.

• DFG-Verfahren: Sachbeihilfen