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Hydrobiologia

, Volume 305, Issue 1–3, pp 85–90 | Cite as

Chromosome bands in freshwater triclads

  • R. Canovai
  • G. Stocchino
  • I. Privitera
  • A. Alberti
  • M. Pala
  • L. Galleni
Biogeography and genetics

Abstract

Four species of Triclads belonging to three families, Dugesia polychroa and Dugesia mediterranea (Dugesiidae), Planaria torva (Planariidae) and Dendrocoelum lacteum (Dendrocoelidae) were studied for chromosome banding: C-banding for all the species, ASG banding for Dugesia polychroa and G-banding for Dugesia polychroa and Dugesia mediterranea. C-banding results for Dugesia lugubris-polychroa group suggest a high level of heterochromatin evolution in the group. Small bands strictly limited to the centromeric region were seen in Dugusia lugubris and this pattern is similar to the patterns of some species belonging to other families, notably Planaria torva and Dendrocoelum lacteum. This could be considered a primitive character. In contrast numerous heterochromatin bands which are useful to characterize the different karyotypes were seen in Dugesia polychroa and Dugesia mediterranea. Our data suggest that heterochromatin is important in freshwater triclad speciation.

Key words

Platyhelminthes triclads chromosome banding speciation 

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Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • R. Canovai
    • 1
  • G. Stocchino
    • 2
  • I. Privitera
    • 1
  • A. Alberti
    • 2
  • M. Pala
    • 2
  • L. Galleni
    • 1
  1. 1.Dipartimento di Coltivazione e Difesa delle Specie Legnose, sezione: Entomologia AgrariaUniversità di PisaItaly
  2. 2.Istituto di ZoologiaUniversità di SassariItaly

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