The Karyotype and C-Banding of Percocypris pingi

Abstract:

Percocypris pingi is one of the endemic fishes in the upper reach of the Yangtze River and is one of the protected fish species in Sichuan Province. In this study, we investigated the ploidy and other cytogenetical characteristics of P. pingi. The karyotype of the renal tissue of P. pingi was examined using PHA injection with air-dry method. The C-band of P. pingi was displayed with modified BSG method. The results showed that the number of chromosomes of P. pingi was 98, and the formula could be expressed as 4n=98=42m+30sm＋10st＋16t, and the arm number (NF) was 170. Sixteen telocentric chromosome of P. pingi was found in this study although unreported in previous studies. Neither small chromosomes nor other heteromorphic chromosomes were found. All the karyotype had the size of the C-band appeared. The types of C-bands of P. pingi were diverse, including centromeric band, telomere band and intermediate band. Multiple C-bands were found in some chromosomes, for example, all types of C-bands were found in m2 and st4. The level of the heterochromatin was 58.824%±0.034%. We confirmed once again that P. pingi was a tetraploid fish. Its chromosomes were ‘plastic’ to some extent based on the karyotype and C-bands, indicating that P. pingi might be adaptable to specific habitats in different regions.