Development and architecture of the nervous system in Cephalocarida and Mystacocarida - Testing the monophyly of Crustacea

点击翻译按钮获取中文摘要

The project continues to investigate the architecture and development of the nervous system in two crustacean taxa, Cephalocarida and Mystacocarida, using various kinds of immunohistochemical techniques. It has been suggested that both taxa are “primitive” crustaceans (i.e. characterized by a high number of plesiomorphic characters), and that Mystacocarida is even the sister group of all other Mandibulata (implying the paraphyly of Crustacea). The development of the nervous system in Hutchinsoniella macracantha (Cephalocarida), in Derocheilocaris remanei and in D. typica (Mystacocarida) will be studied using antibody staining against acetylated and tyrosinated α-tubulin and against synapsin. In addition, single serotonin, FMRFamide and histamine immunoreactive neurons will be characterized in order to reveal homologous cell patterns. Immunohistochemical techniques of this nature are now well established in various arthropods and potential sistergroups and allow maximum comparability between taxa. In addition, the gene expression pattern of even-skipped will be studied in combination with immunohistochemical techniques in order to identify single pioneer neurons which have played an important role in the debate on hexapod-crustacean relationships. In all these respects this study of cephalocarids and mystacocarids will fill important gaps in our understanding of deep arthropod and ultimately deep metazoan phylogeny.