The morphogenesis of ephyra in Coronatae (Cnidaria,Scyphozoa) |
| |
Authors: | Norman Eggers Gerhard Jarms |
| |
Institution: | 1.Biozentrum Grindel und Zoologisches Museum,Universit?t Hamburg,Hamburg,Germany |
| |
Abstract: | The morphogenesis of ephyrae of Atorella vanhoeffeni Bigelow, 1909 (Werner, 1967) and of Nausithoe maculata Jarms, 1990 during strobilation is described. We found differences in the developmental pattern of marginal structures and structural
changes of longitudinal muscle tubes in particular. During strobilation the polyp’s tetraradiate symmetry is passed to the
ephyra of both taxa as a tetraradiate central symmetry that we consider a major plesiomorphic character. The present results
also indicate divergent patterns of ephyra development during strobilation that lead to variable marginal symmetries of ephyrae
and thus of medusae. Therefore, the marginal symmetry of medusae of N. maculata is octoradiate and of A. vanhoeffeni is hexaradiate. We conclude the latter is stated as derived pattern. These results lead us to maintain both families Nausithoidae
and Atorellidae. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|