Delta-Notch signaling is essential for somitogenesis in vertebrate embryos. In a search for genes that control somite formation in zebrafish we have identified two paralogues encoding proteins related to Nrarp (Notch regulated ankyrin repeat protein). Zebrafish nrarp-a and-b encode small proteins with two ankyrin repeat domains. Here, we report the expression patterns of both genes in normal and mutant embryos.