Abstract
We present a genome assembly from an individual male Cauchas fibulella (Speedwell Longhorn; Arthropoda; Insecta; Lepidoptera; Adelidae). The assembly contains two haplotypes with total lengths of 578.63 megabases and 573.48 megabases. The whole sequence for haplotype 1 is scaffolded into 25 chromosomal pseudomolecules, including the Z chromosome. Most of haplotype 2 (97.29%) is scaffolded into 25 chromosomal pseudomolecules, also including a Z chromosome. The mitochondrial genome has also been assembled, with a length of 15.77 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.