Abstract
In developing insect eggs the cells of the blastoderm adopt either an embryonic or an extraembryonic fate. The extraembryonic tissue consists of epithelia, termed amnion and serosa, which wrap the germ band embryo. The serosa develops directly from part of the blastoderm and surrounds the embryo as well as the yolk. The amnion develops from the margins of the germ band and in most insect species generates a transient ventral cavity for the developing embryo. The amniotic cavity and the serosa have been reduced in the course of dipteran evolution. The insect order of Diptera includes the paraphyletic Nematocera, including gnats and mosquitoes, and the more derived monophyletic Brachycera, the true flies. Nematocera develop within an amniotic cavity and the surrounding serosa, whereas cyclorrhaphan Brachycera do not. This observation implies that the amnion and serosa have been reduced before the radiation of the monophyletic cyclorrhaphan flies. Here I show that an amniotic cavity is formed during embryogenesis of the horsefly Haematopota pluvialis (Tabanidae) and the dancefly Empis livida (Empididae). The results suggest that extraembryonic tissue was reduced in the stem lineage of cyclorrhaphan flies, with consequences for the molecular basis of pattern formation along the anterior-posterior axis of the embryo.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 21 October 1999 / Accepted: 17 January 2000
Rights and permissions
About this article
Cite this article
Schmidt-Ott, U. The amnioserosa is an apomorphic character of cyclorrhaphan flies. Dev Gene Evol 210, 373–376 (2000). https://doi.org/10.1007/s004270000068
Issue Date:
DOI: https://doi.org/10.1007/s004270000068