Complete mitochondrial genome of Acanthopsyche nigraplaga (Lepidoptera: Psychidae)

Abstract We report the mitochondrial genome (mitogenome) of a case-making moth Acanthopsyche nigraplaga Wileman, 1911 (Lepidoptera: Psychidae). The 15,704 bp long complete mitogenome comprises a typical set of genes [13 protein-coding genes (PCGs), 2 rRNA genes, and 22 tRNA genes] and one major non-coding, A + T-rich region, with an arrangement identical to that observed in most lepidopteran mitogenomes. Twelve of the 13 PCGs of the A. nigraplaga mitogenome initiate with a typical ATN start codon, however COI contains the atypical CGA start codon that is common for lepidopteran COI genes. A phylogenetic analysis using concatenated nucleotide sequences of the 13 PCGs and 2 rRNA genes using the Bayesian inference method fully resolved A. nigraplaga in a monophyletic clade within the Psychidae. Acanthopsyche nigraplaga was situated in a sister position to Eumeta variegata and Mahasena oolona with high nodal support. As more mitogenome sequences are available further scrutinized analysis for the superfamily Tineoidea including Psychidae will be possible.

Acanthopsyche nigraplaga (Psychidae: Lepidoptera) is distributed in Korea, Japan, China, and India (Byun et al. 1996;Roh et al. 2019). Members of the family Psychidae are casemaking moths, also called 'bagworms', owing to the casemaking habit of their larvae. Psychidae is a relatively small family with fewer than 1,350 described species grouped into 241 genera worldwide (Sobczyk 2011), and a limited number of mitochondrial genome sequences have been published. Here, we sequenced the complete mitogenome of A. nigraplaga for a subsequent mitogenome-based phylogenetic analysis for the superfamily Tineoidea, in which the family Psychidae is included.
The A. nigraplaga mitogenome (GenBank acc. no. MT883999) is 15,704 bp in length which is similar to those reported in other Tineoidea including those from Psychidae (Li et al. 2017;Arakawa et al. 2018;Jeong et al. 2018;Roh et al. 2019). The A. nigraplaga mitogenome contains a typical set of genes [2 rRNA genes, 22 tRNA genes, and 13 proteincoding genes (PCGs)] and a 258 bp-long major non-coding A þ T-rich region. The arrangement of genes in the A. nigraplaga mitogenome is the same as that reported in most lepidopteran species (Kim et al. 2010). This arrangement differs from that found in the ancient lepidopteran superfamilies, such as Hepialoidea (Timmermans et al. 2014) and Nepticuloidea (Cao et al. 2012), and from the ancestral arrangement found in the majority of insects (Boore 1999). The A/T content was 77.72% in PCGs, 81.79% in tRNAs, 83.49% in lrRNA, 85.99% in srRNA, and 96.90% in the A þ Trich region. Twelve of the 13 PCGs of A. nigraplaga contain ATN as the start codon, except for COI, which initiates with an alternative codon (CGA) as has frequenctly been observed in other lepidopteran insects (Kim et al. 2012).
A phylogenetic analysis was performed using the concatenated nucleotide sequences of 13 PCGs and two rRNA genes (12,368 bp); ten species of Tineoidea, including A. nigraplaga, were included in the analysis and represented four families (Psychidae, Tineidae, Meessiidae, and Gracillariidae). Stigmella roborella, a species classified in the Nepticuloidea, was utilized as the outgroup. The Bayesian inference (BI) method implemented in CIPRES Portal v. 3.1 (Miller et al. 2010) was conducted using MrBayes ver. 3.2.7 (Ronquist et al. 2012). PartitionFinder2 (Lanfear et al. 2012(Lanfear et al. , 2014(Lanfear et al. , 2016 was used to search for the optimal partitions and the corresponding optimal models of substitution using the 'greedy' The phylogenetic analysis resolved the family Psychidae as a monophyletic taxon with full support (Figure 1). Within the Psychidae, A. nigraplaga was inferred as a sister taxon in a basal position to Eumeta variegata and Mahasena oolona, and Dahlica ochrostigma was placed as the most basal lineage in the Psychidae (Figure 1). With respect to familial relationships, the Psychidae and Tineidae formed a sister group with low support [(Bayesian posterior probability (BPP) ¼ 0.58)]. The Meessiidae was placed in a sister relationship to the Psychidae and Tineidae, but support for this relationship was relatively low as well (BPP ¼ 0.55). The Gracillariidae was fully resolved as the most basal lineage of the Tineoidea. Similar phylogenetic results for the familial relationships were obtained by Robinson (1988) and Regier et al. (2013). In contrast, some studies have shown the Psychidae to be the basal group for Tineidae (Mitter et al. 2017;Mutanen et al. 2010;Regier et al. 2015). More complete mitogenome sequences are necessary for investigating the familial relationships of Tineoidea.

Disclosure statement
No potential conflict of interest was reported by the authors.

Data availability statement
The genome sequence data that support the findings of this study are openly available in GenBank of NCBI at https://www.ncbi.nlm.nih.gov/ nuccore/MT883999.1