The genome sequence of the Kent black arches, Meganola albula (Denis & Schiffermüller, 1775)

We present a genome assembly from an individual male Meganola albula (the Kent black arches; Arthropoda; Insecta; Lepidoptera; Nolidae). The genome sequence is 405 megabases in span. Most of the assembly (99.95%) is scaffolded into 30 chromosomal pseudomolecules with the Z sex chromosome assembled. The mitochondrial genome has also been assembled and is 15.4 kilobases in length.


Background
Kent Black Arches, or Meganola albula, belonging to the moth family Nolidae (Zahiri et al., 2013) and one of the 80 species in the genus Meganola (Cha et al., 2019), was first described in 1775 by Denis & Schiffermüller in Austria. The species bears close similarity to Scarce Black Arches (Nola aerugula), another species found in similar coastal UK habitats as Kent Black Arches (NBN Atlas;Õunap et al., 2021). M. albula wings have a white ground colour with a curved brown medial band, white curved sub-terminal line and brown terminal field (Perveen & Khan, 2017) . The M. albula wingspan is 16-20 mm (Cha et al., 2019;Kiss, 2017;Zahiri et al., 2012). The head and thorax are white, and the abdomen is brown (Cha et al., 2019).
This species is widely distributed across the Palearctic region (Tshistjakov, 2008); most observations have been reported across Western Europe, seen as far north as the southern coast of Finland. M. albula is sparsely distributed across the UK, primarily found in coastal regions. Early sightings within the UK were along the southern coast of England (Heath & Alford, 1973), primarily within counties of Kent and Sussex, but the species is more frequently seen further north along the south-east coastline (NBN Atlas). M. albula occupies a variety of coastal habitats, including coastal marshes (Zilli, 2014) and woodlands, with the larva feeding on Rubus caesius (Seymour, 2018), Fragaria (strawberry), Potentilla, Vaccinium, Lotus, Trifolium and Mentha (Tshistjakov, 2008).
The adult M. albula is most commonly seen within the UK and western Europe between June and August, with most sightings occurring during the month of July (NBN Atlas), flying in a single generation. In eastern regions (far eastern Russian, eastern China) multiple flight generations are seen, from towards the end of May till June and then from July into early August (Tshistjakov, 2008). This species overwinters as small larvae (Skinner & Wilson, 2009).

Genome sequence report
The genome was sequenced from one male M. albula specimen ( Figure 1) collected from Wytham Woods, Berkshire, UK (latitude 51.769, longitude -1.33). A total of 43-fold coverage in Pacific Biosciences single-molecule HiFi long reads and 108-fold coverage in 10X Genomics read clouds was generated. Primary assembly contigs were scaffolded with chromosome conformation Hi-C data. Manual assembly curation corrected 10 missing or misjoins, reducing the scaffold number by 15%.
The final assembly has a total length of 405.2 Mb in 34 sequence scaffolds with a scaffold N50 of 14.3 Mb (Table 1).
Most (99.95%) of the assembly sequence was assigned to 30 chromosomal-level scaffolds, representing 29 autosomes and the Z sex chromosome (Figure 2- Figure 5; Table 2). Chromosome-scale scaffolds confirmed by the Hi-C data are named in order of size. While not fully phased, the assembly deposited is of one haplotype. Contigs corresponding to the second haplotype have also been deposited. The assembly has a BUSCO v5.3.2 (Manni et al., 2021) completeness of 98.4% (single 98.1%, duplicated 0.4%) using the lepidoptera_odb10 reference set.

Sample acquisition and nucleic acid extraction
Two M. albula specimens (ilMegAlbu1 and ilMegAlbu2) of undetermined sex were collected using a light trap in Wytham Woods, Berkshire, UK (latitude 51.769, longitude -1.33) by Douglas Boyes (University of Oxford), who also identified the species. The specimens were identified by Douglas Boyes and snap-frozen on dry ice. A second specimen (ilMegAlbu4) of undetermined sex was collected using an aerial net from Hartslock Nature Reserve (latitude 51.51, longitude -1.11) by Ian Sims (British Entomological and Natural History Society). The specimen was identified by Ian Sims and David Lees (Natural History Museum, London) and snap-frozen on dry ice.
DNA was extracted at the Tree of Life laboratory, Wellcome Sanger Institute. The ilMegAlbu1 sample was weighed and dissected on dry ice. Whole organism 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 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

Sequencing
Pacific Biosciences HiFi circular consensus and 10X Genomics read cloud DNA sequencing libraries were constructed according to the manufacturers' instructions. Poly(A) RNA-Seq libraries were constructed using the NEB Ultra II RNA Library Prep kit. DNA and RNA sequencing was performed by the Scientific Operations core at the WSI on Pacific Biosciences SEQUEL II (HiFi) and Illumina NovaSeq 6000 (RNA-Seq and 10X) instruments. Hi-C data were also generated from whole organism tissue of ilMegAlbu2 using the Arima v2 kit and sequenced on the Illumina NovaSeq 6000 instrument.

Genome assembly
Assembly was carried out with Hifiasm (Cheng et al., 2021) and haplotypic duplication was identified and removed with purge_dups (Guan et al., 2020). One round of polishing  et al., 2019). The assembly was checked for contamination as described previously (Howe et al., 2021). Manual curation was performed using HiGlass (Kerpedjiev et al., 2018) and Pretext (Harry, 2022). The mitochondrial genome was assembled using MitoHiFi (Uliano-Silva et al., 2021), which performed annotation using MitoFinder (Allio et al., 2020). The genome was analysed and BUSCO scores generated within the BlobToolKit environment (Challis et al., 2020). Table 3 contains a list of all software tool versions used, where appropriate.