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Abstract We present the first long-read de novo assembly and annotation of the luna moth (Actias luna) and provide the full characterization of heavy chain fibroin (h-fibroin), a long and highly repetitive gene (>20 kb) essential in silk fiber production. There are >160,000 described species of moths and butterflies (Lepidoptera), but only within the last 5 years have we begun to recover high-quality annotated whole genomes across the order that capture h-fibroin. Using PacBio HiFi reads, we produce the first high-quality long-read reference genome for this species. The assembled genome has a length of 532 Mb, a contig N50 of 16.8 Mb, an L50 of 14 contigs, and 99.4% completeness (BUSCO). Our annotation using Bombyx mori protein and A. luna RNAseq evidence captured a total of 20,866 genes at 98.9% completeness with 10,267 functionally annotated proteins and a full-length h-fibroin annotation of 2,679 amino acid residues. 

Abstract While most species of butterflies and moths (Lepidoptera) have entirely terrestrial life histories, ∼0.5% of the described species are known to have an aquatic larval stage. Larvae of aquatic Lepidoptera are similar to caddisflies (Trichoptera) in that they use silk to anchor themselves to underwater substrates or to build protective cases. However, the physical properties and genetic elements of silks in aquatic Lepidoptera remain unstudied, as most research on lepidopteran silk has focused on the commercially important silkworm, Bombyx mori. Here, we provide high-quality PacBio HiFi genome assemblies of 2 distantly-related aquatic Lepidoptera species [Elophila obliteralis (Pyraloidea: Crambidae) and Hyposmocoma kahamanoa (Gelechioidea: Cosmopterigidae)]. As a step toward understanding the evolution of underwater silk in aquatic Lepidoptera, we used the genome assemblies and compared them to published genetic data of aquatic and terrestrial Lepidoptera. Sequences of the primary silk protein, h-fibroin, in aquatic moths have conserved termini and share a basic motif structure with terrestrial Lepidoptera. However, these sequences were similar to aquatic Trichoptera in that the percentage of positively and negatively charged amino acids was much higher than in terrestrial Lepidoptera, indicating a possible adaptation of silks to aquatic environments. 

ABSTRACT Synanthropic species live in close association with, or benefit from, humans. Despite their potential impacts to human health, little is known about the mechanisms driving synanthropic life‐history evolution, evolutionary forces shaping diet among synanthropes, or how these combined factors affect population dynamics and/or speciation. The Tineidae moth family contains several synanthropic species, including the globally distributed pest speciesTineola bissellellia, that contribute to the ~$1 billion worth of damage caused annually by keratinophagous synanthropes. Synanthropy among Tineidae is associated with a wide range of dietary strategies. While most tineids display obligate detritivory, synanthropic species are typically either facultatively or obligately keratinophagous. However, little is known about evolutionary relationships within Tineidae, hampering efforts to investigate the relationship between synanthropy and diet evolution. Here, to address this challenge, we extracted DNA from 39 tineid samples and two outgroups, including the closely relatedTineolaandTineagenera, and generated genome‐wide sequence data for thousands of ultraconserved elements (UCEs). Our phylogenetic analyses, using a concatenated maximum‐likelihood‐based approach, resulted in a well‐supported, fully resolved phylogeny that demonstrates synanthropy has evolved multiple times and is consistently associated with facultative and obligate keratinophagy. Bayesian divergence time estimation indicates Cretaceous divergence among deep‐branching tineid lineages, an ancestral origin of facultative keratinophagy, and a recent origin of the most economically important synanthropic pest,Tineola bissellellia,from within genusTinea. Taken together, our results suggest that a shift to facultative keratinophagy was a key evolutionary innovation that has fuelled the repeated evolution of synanthropic life histories among this deep‐diverging moth family.