Karyotype of a fresh water planarian phagocata kawakatsui and chromosomal variations in neo blasts of regenerating pieces
Teshirogi, W.; Ishida, S.
Annotationes Zoologicae Japonenses 52(3): 191-202
1979
ISSN/ISBN: 0003-5092 Accession: 005777792
Using the squash method, research on the karyotype of P. kawakatsui and chromosomal variations found in neoblasts of regenerating pieces were performed. Observations were made on the meiotic divisions of primary spermatocytes and oocytes. The chromosome number of this species is 2n = 24 and n = 12. The karyotype consists of 5 pairs of metacentric chromosomes and 7 pairs of submetacentric chromosomes. Chromosome 1 is particularly large in size and metacentric; chromosome 2 is medium and submetacentric, while all the others are distinctly small. Although many neoblasts in regenerating pieces have the chromosome number of 2n = 24, some others have different chromosome numbers, as has already been pointed out in P. teshirogii by Teshirogi and Sasaki (1977). No abnormality in chromosome numbers was found during the meiosis of spermatocytes and oocytes. [This study is relevant to taxonomy.].