The genome sequence of the Minor Shoulder-knot, Brachylomia viminalis (Fabricius, 1777)

We present a genome assembly from an individual male Brachylomia viminalis (the Minor Shoulder-knot; Arthropoda; Insecta; Lepidoptera; Noctuidae). The genome sequence is 782.2 megabases in span. Most of the assembly is scaffolded into 31 chromosomal pseudomolecules, including the Z sex chromosome. The mitochondrial genome has also been assembled and is 16.15 kilobases in length. Gene annotation of this assembly on Ensembl identified 20,191 protein coding genes.


Background
Brachylomia viminalis (Minor Shoulder-knot) is a widespread noctuid moth of damp habitats found across the Palaearctic from Europe to Japan.In Britain, the abundance and distribution of this species has decreased significantly since the 1970s and it continues to decline (Randle et al., 2019).Consequently, (Fox et al., 2019) classified this moth as 'nearthreatened'.The adult moth is attracted to light, and also feeds at flowers during its flight season in July and August.
The adult moth is quite small, with a forewing length of 13-15 mm, and is variable in colouration.Usually, the ground colour is light grey but darker forms occur, with melanistic forms appearing over most of its range in Britain.The specimen selected for genome sequencing here was of the light grey colour form, f. stricta.The two short black streaks at the base of the forewing are diagnostic and give rise to the moth's common name: the Minor Shoulder-knot.'Shoulderknots' were fashionable in the late 1600s and were a set of ribbons on a coat in a contrasting colour.The dark streaks are thought to resemble this frippery (Marren, 2019).
The eggs are laid either singly or in small groups on the twigs of a wide variety of willow species, predominantly grey willow (Salix cinerea), and it overwinters as this stage.Eggs hatch in the spring and the larvae initially feed on terminal shoots.Later larval stages feed nocturnally and hide by day in spinnings on the leaves of terminal shoots (Heath & Emmet, 1983).Pupation occurs in leaf litter or just under the soil surface.
The genome of B. viminalis was sequenced as part of the Darwin Tree of Life Project, a collaborative effort to sequence all named eukaryotic species in the Atlantic Archipelago of Britain and Ireland.Here we present a chromosomally complete genome sequence for B. viminalis, based on one male specimen from Wytham Woods, Oxfordshire, UK.

Genome sequence report
The genome was sequenced from one male Brachylomia viminalis (Figure 1) collected from Wytham Woods, Oxfordshire, UK (51.77,.A total of 51-fold coverage in Pacific Biosciences single-molecule HiFi long reads and 78fold coverage in 10X Genomics read clouds were generated.Primary assembly contigs were scaffolded with chromosome conformation Hi-C data.Manual assembly curation corrected 22 missing joins or mis-joins and removed 3 haplotypic duplication, reducing the assembly length by 0.43% and increasing the scaffold number by 4.88%, and decreasing the scaffold N50 by 0.85%. The final assembly has a total length of 782.2 Mb in 42 sequence scaffolds with a scaffold N50 of 26.8 Mb (Table 1).Most (99.9%) of the assembly sequence was assigned to 31 chromosomal-level scaffolds, representing 30 autosomes and the Z sex chromosome.Chromosome-scale scaffolds confirmed by the Hi-C data are named in order of size (Figure 2-Figure 5; Table 2).While not fully phased, the assembly deposited is of one haplotype.Contigs corresponding to the second haplotype have also been deposited.The mitochondrial genome was also assembled and can be found as a contig within the multifasta file of the genome submission.
Metadata for specimens, spectral estimates, sequencing runs, contaminants and pre-curation assembly statistics can be found at https://links.tol.sanger.ac.uk/species/988081.

Sample acquisition and nucleic acid extraction
A male Brachylomia viminalis (specimen ID Ox000522, individual ilBraVimi1) was collected from Wytham Woods,   Oxfordshire (biological vice-county Berkshire), UK (latitude 51.77, longitude -1.33) on 2020-06-25 using a light trap.Douglas Boyes (University of Oxford) collected and identified the specimen.The specimen was snap-frozen on dry ice.
DNA was extracted at the Tree of Life laboratory, Wellcome Sanger Institute (WSI).The ilBraVimi1 sample was weighed and dissected on dry ice with tissue set aside for Hi-C sequencing.Abdomen tissue was disrupted using a Nippi Powermasher fitted with a BioMasher pestle.High molecular weight (HMW) DNA was extracted using the Qiagen MagAttract HMW DNA extraction kit.Low molecular weight DNA was removed from a 20 ng aliquot of extracted DNA using the 0.8X AMpure XP purification kit prior to 10X Chromium sequencing; a minimum of 50 ng DNA was submitted for 10X sequencing.HMW DNA was sheared into an average fragment size of 12-20 kb in a Megaruptor 3 system with speed setting 30.Sheared DNA was purified by solid-phase reversible immobilisation using AMPure PB beads with a 1.8X ratio of beads to sample to remove the shorter fragments and concentrate the DNA sample.The concentration of the sheared and purified DNA was assessed using a Nanodrop spectrophotometer and Qubit Fluorometer and Qubit dsDNA High Sensitivity Assay kit.Fragment size distribution was evaluated by running the sample on the FemtoPulse system.

Sequencing
Pacific Biosciences HiFi circular consensus and 10X Genomics read cloud DNA sequencing libraries were constructed according to the manufacturers' instructions.DNA sequencing was performed by the Scientific Operations core at the WSI on Pacific Biosciences SEQUEL II (HiFi) and Illumina NovaSeq 6000 (10X) instruments.Hi-C data were also generated A Hi-C map for the final assembly was produced using bwa-mem2 (Vasimuddin et al., 2019) in the Cooler file format (Abdennur & Mirny, 2020).To assess the assembly metrics, the k-mer completeness and QV consensus quality values were calculated in Merqury (Rhie et al., 2020).This work  et al., 2020) andBUSCO scores (Manni et al., 2021;Simão et al., 2015) were calculated.
Table 3 contains a list of relevant software tool versions and sources.

Genome annotation
The BRAKER2 pipeline (Brůna et al., 2021) was used in the default protein mode to generate annotation for the Brachylomia viminalis assembly (GCA_937001585.2) in Ensembl Rapid Release.

Wellcome Sanger Institute -Legal and Governance
The materials that have contributed to this genome note have been supplied by a Darwin Tree of Life Partner.The submission of materials by a Darwin Tree of Life Partner is subject to the 'Darwin Tree of Life Project Sampling Code of Practice', which can be found in full on the Darwin Tree of Life website here.By agreeing with and signing up to the Sampling Code of Practice, the Darwin Tree of Life Partner agrees they will meet the legal and ethical requirements and standards set out within this document in respect of all samples acquired for, and supplied to, the Darwin Tree of Life Project.
Further, the Wellcome Sanger Institute employs a process whereby due diligence is carried out proportionate to the

Software tool Version
nature of the materials themselves, and the circumstances under which they have been/are to be collected and provided for use.The purpose of this is to address and mitigate any potential legal and/or ethical implications of receipt and use of the materials as part of the research project, and to ensure that in doing so we align with best practice wherever possible.The overarching areas of consideration are: • Ethical review of provenance and sourcing of the material

Stephen Richards
Baylor College of Medicine, Houston, TX, USA This is yet another almost perfect genome assembly from the Darwin Tree of Life project from a near-threatened lepidopteran species.The genome quality is amazing, and I had no trouble getting access to it at EBI.The tree of life project is moving from success to success, and I hope they will continue to get funding to accelerate into sequencing of the rest of the UK.I hope that this reference genome will be used as a basis for population genomics to help guide how and where to best protect this species and prevent further declines.An excellent job and congratulations to all involved!Is the rationale for creating the dataset(s) clearly described?Yes Are the protocols appropriate and is the work technically sound?Yes

Are sufficient details of methods and materials provided to allow replication by others? Yes
Are the datasets clearly presented in a useable and accessible format?Yes Competing Interests: No competing interests were disclosed.
Reviewer Expertise: Arthropod reference genome generation and analysis, general genomics.
I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

Faezah Mohd Salleh
Department of Biosciences, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia Thank you for inviting me to review this genome assembly work.An important contribution to the insect community.
The paper is clearly written.All metadata, genome statistics, and related links have been provided and are accessible.The research flow has been described thoroughly and is highly reproducible.
I do not have further suggestions.

Is the rationale for creating the dataset(s) clearly described? Yes
Are the protocols appropriate and is the work technically sound?Yes

Are sufficient details of methods and materials provided to allow replication by others? Yes
Are the datasets clearly presented in a useable and accessible format?Yes Competing Interests: No competing interests were disclosed.
Reviewer Expertise: Biodiversity mitogenomics I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

Figure 2 .
Figure 2. Genome assembly of Brachylomia viminalis, ilBraVimi1.2:metrics.The BlobToolKit Snailplot shows N50 metrics and BUSCO gene completeness.The main plot is divided into 1,000 size-ordered bins around the circumference with each bin representing 0.1% of the 781,437,518 bp assembly.The distribution of scaffold lengths is shown in dark grey with the plot radius scaled to the longest scaffold present in the assembly (38,942,460 bp, shown in red).Orange and pale-orange arcs show the N50 and N90 scaffold lengths (26,683,488 and 18,613,057 bp), respectively.The pale grey spiral shows the cumulative scaffold count on a log scale with white scale lines showing successive orders of magnitude.The blue and pale-blue area around the outside of the plot shows the distribution of GC, AT and N percentages in the same bins as the inner plot.A summary of complete, fragmented, duplicated and missing BUSCO genes in the lepidoptera_odb10 set is shown in the top right.An interactive version of this figure is available at https://blobtoolkit.genomehubs.org/view/ilBraVimi1.1/dataset/CAKZJQ01.1/snail.

Figure 5 .
Figure 5. Genome assembly of Brachylomia ilBraVimi1.2:Hi-C contact map of the ilBraVimi1.2assembly, visualised using HiGlass.Chromosomes are shown in order of size from left to right and top to bottom.An interactive version of this figure may be viewed at https://genome-note-higlass.tol.sanger.ac.uk/l/?d=HQl63gQkR1yHz83QJbO33w.
doi.org/10.21956/wellcomeopenres.21642.r60400© 2023 Salleh F. This is an open access peer review report distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Peer Review Current Peer Review Status: Version 1
This is an open access peer review report distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.