Open AccessChromosomenteilung oder ‐verdopplung in Macrostomum lignano (Macrostomorpha, Plathelminthes) – Bemerkungen zur Chromosomenzahl in ‘archoophoren Turbellarien’
Author(s) -
Egger B.,
Ishida S.
Publication year - 2005
Publication title -
journal of zoological systematics and evolutionary research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.769
H-Index - 50
eISSN - 1439-0469
pISSN - 0947-5745
DOI - 10.1111/j.1439-0469.2005.00300.x
Subject(s) - biology , ploidy , giemsa stain , orcein , chromosome , metaphase , karyotype , microbiology and biotechnology , staining , genetics , gene
Mitotic metaphase plates of a new species of the genus Macrostomum were studied using conventional Giemsa staining, Orcein staining and semi‐thin sections stained after Richardson. Because of the ease in culturing it, this species has the potential to become the new model organism for developmental and evolutionary studies among the lower metazoa. The chromosome number was found to be 2 n = 8. Reaching a relative length of 45.9% of the haploid genome size, the chromosomes of one pair were significantly larger than all other chromosomes. Of the smaller pairs, chromosomes of one pair were slightly larger (relative length of 21.3%) than the chromosomes of the remaining two pairs (each with a relative length of 16.4%). All chromosomes were metacentric (2 m + 2 m + 2 m + 2 m ). For the first time, a diploid chromosome set of four pairs was described for the genus, as compared with previous studies showing predominantly 2 n = 6 for 20 different Macrostomum species.