Abstract
In Mesocyclops edax S.A. Forbes, 2n=14, a North American copepod, the females are heterozygous for several interchanges leading to the formation of large rings of chromosomes (rings of 14, or of 12 plus 1 bivalent) at meiotic metaphase, comparable to those of the plant Oenothera, although no chiasmata are present. The chromosomes are more or less metacentric and have large terminal H-segments. In the rings homologous arms are held together by connecting fibers which insert close to the euchromatin-heterochromatin junctions. Coordinated orientation of the zigzag type seems to be the role.
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Chinnappa, C.C., Victor, R. Achiasmatic meiosis and complex heterozygosity in female cyclopoid copepods (Copepoda, Crustacea). Chromosoma 71, 227–236 (1979). https://doi.org/10.1007/BF00292825
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DOI: https://doi.org/10.1007/BF00292825