01365nas a2200169   4500008004100000245009400041210006900135300001200204490000700216520078500223100001701008700002301025700002101048700002601069700002201095856007801117       1999                        eng d00aA karyological study on populations of Dugesia gonocephala s.I. (Turbellaria, Tricladida)0 akaryological study on populations of Dugesia gonocephala sI Turb  a245-2530 v663 a<p>A karyological analysis was carried out on sexual and fissi-parous populations of planarians belonging to the &rsquo;Dugesia gonocephala group&rsquo;, collected in localities of the Mediterranean area, Morocco, and Yemen. Euploid (diploid and triploid) chromosome sets are observed in populations reproducing only sexually, whereas hyperdiploid and aneutriploid complements characterize agamous and fissiparous strains. Aneuploidy may occur either associated with an increase in the chromosome number or as a product of rearrangements in numerically balanced chromosome sets. Mitotically unstable B-chromosomes are present in all aneu-ploid populations. The variety of karyological characteristics encountered is discussed from a cytogenetic and cytotaxonomic standpoint.</p>
1 aDeria, Paolo1 aColognatoa, Renato1 aRossia, Leonardo1 aSalvettia, Alessandra1 aBatistoni, Renata  uhttp://www.tandfonline.com/doi/abs/10.1080/11250009909356262#.UsA5-_ZLraQ