| achiasmate male meiosis in two cymatia species (hemiptera, heteroptera, corixidae). | the karyotype and male meiosis, with a particular focus on the presence or absence of chiasmata between the homologs, were studied in the water boatman species cymatia rogenhoferi (fieber) and cymatia coleoptrata (fabricius) (corixidae, cymatiainae). it is shown that the species have 2n = 33 (28a+2m+x1x2y) and 2n = 24 (20a+2m+xy) respectively, post-reduction of sex chromosomes, and achiasmate meiosis of an alignment type in males. cytogenetic and some morphological diagnostic characters separati ... | 2015 | 26807038 |