Abstract
We present a genome assembly from a male specimen of Grampus griseus (Risso's dolphin; Chordata; Mammalia; Artiodactyla; Delphinidae). The assembly contains two haplotypes with total lengths of 2 667.07 megabases and 2 403.96 megabases. Most of haplotype 1 (89.46%) is scaffolded into 23 chromosomal pseudomolecules, including the X and Y sex chromosomes. Haplotype 2 was assembled to scaffold level. The mitochondrial genome has also been assembled, with a length of 16.39 kilobases.