Abstract
We present a genome assembly from an individual male Balaenoptera physalus (fin whale; Chordata; Mammalia; Artiodactyla; Balaenopteridae). The assembly contains two haplotypes with total lengths of 3 442.54 megabases and 2 850.21 megabases. Most of haplotype 1 (79.11%) 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 16.4 kilobases. This assembly was generated as part of the Darwin Tree of Life project, which produces reference genomes for eukaryotic species found in Britain and Ireland.