Figure 3
Karyotype reconstruction on metaphase chromosomes of T. blanchardi and of the T. tubifex lineages of the Lambro River. A. The diploid T. blanchardi (2n = 50), consisting of 42 meta- and submetacentric chromosomes and 8 acrocentric chromosomes; B. the triploid Tubifex (lineage 2a, 3n = 75) composed of 64 meta submetacentric chromosomes and 11 acrocentric chromosomes; C. the tetraploid Tubifex (lineage 2b, 4n = 100) composed of 87 meta-, submetacentric chromosomes and 13 acrocentric chromosomes, with one large metacentric chromosome marker (arrowhead); D. the hexaploid Tubifex (lineage 2c, 6n = 150), composed of 128 meta- submetacentric chromosomes and 22 acrocentric chromosomes, with two large metacentric chromosome markers (arrowheads); E. the tetraploid Tubifex (lineages 3a, 2n = 100) composed of 74 meta- or submetacentric and 26 acrocentric chromosomes, with four large metacentric chromosome markers (arrowheads); F. the tetraploid Tubifex (lineages 3b, 2n = 100) composed of 69 meta- or submetacentric chromosomes and 31 acrocentric chromosomes, with four large metacentric chromosome markers (arrowheads). Numbers indicate the meta- or submetacentric chromosomes; underlined numbers indicate acrocentric chromosomes. Scale bars are 4 μm in A, 3 μm in B, 2.5 μm in D and 2 μm in C, E, and F.