The karyotypes of Hapalogenys nitens (Richardson and H. Mucronatus (Eydoux et Souleyet)

The karyotypes of Hapalogenys nitens and H.mucronatus were examined from their renal tissues by PHA injection-air drying method. Both of the two species have a diploid chromosome number of 48, and their karyotype formulae are 2m+8sm+2st+36t, HF=58 and 2m+8sm+14st+24t, NF=58, respectively. The t5 and t16 chromosome pairs in the karyotype of H.nitens and the t7 chromosome pair in the karyotype of H.mucronatus are chromosomes with secondary constrictions. The characteristics of karyotypes in the two species are in accordance with the typical characters of the karyotype in the higher group of fish evolutionary taxonomy.